* [PATCH v9 01/24] KVM: Make device name configurable
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 02/24] KVM: Move architecture capability Kconfigs to header defines Steffen Eiden
` (23 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Allow KVM implementations to choose alternative device names. This is
especially useful for architectures providing multiple KVM
implementations simultaneously. Architectures providing multiple KVM
implementations must compile the KVM common code once per implementation
and mangle symbols.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/gmap/trace_gmap.h | 4 +++-
arch/s390/kvm/s390/Makefile | 2 +-
include/linux/kvm_host.h | 4 ++++
include/trace/events/kvm.h | 8 +++++++-
virt/kvm/Makefile.kvm | 5 +++++
virt/kvm/async_pf.c | 5 ++++-
virt/kvm/eventfd.c | 3 ++-
virt/kvm/kvm_main.c | 32 +++++++++++++++++---------------
8 files changed, 43 insertions(+), 20 deletions(-)
diff --git a/arch/s390/kvm/gmap/trace_gmap.h b/arch/s390/kvm/gmap/trace_gmap.h
index 15ec88bdce55..78d26dae59f9 100644
--- a/arch/s390/kvm/gmap/trace_gmap.h
+++ b/arch/s390/kvm/gmap/trace_gmap.h
@@ -4,8 +4,10 @@
#include <linux/tracepoint.h>
+#undef UNPACK_KVM
+#define UNPACK_KVM(name) name
#undef TRACE_SYSTEM
-#define TRACE_SYSTEM kvm
+#define TRACE_SYSTEM UNPACK_KVM(KVM_DEV_NAME)
#undef TRACE_INCLUDE_PATH
#define TRACE_INCLUDE_PATH ../gmap
#undef TRACE_INCLUDE_FILE
diff --git a/arch/s390/kvm/s390/Makefile b/arch/s390/kvm/s390/Makefile
index 762a63826423..b91334db90a2 100644
--- a/arch/s390/kvm/s390/Makefile
+++ b/arch/s390/kvm/s390/Makefile
@@ -4,7 +4,7 @@ KVM := ../../../../virt/kvm
include $(srctree)/virt/kvm/Makefile.kvm
include $(srctree)/arch/s390/kvm/gmap/Makefile
-ccflags-y := -I$(src) -I$(srctree)/arch/s390/kvm/gmap
+ccflags-y += -I$(src) -I$(srctree)/arch/s390/kvm/gmap
kvm-y += s390.o intercept.o interrupt.o priv.o sigp.o
kvm-y += diag.o gaccess.o guestdbg.o vsie.o pv.o
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 586f6e8bb81b..160e3e64ec6d 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -45,6 +45,10 @@
#include <asm/kvm_host.h>
#include <linux/kvm_dirty_ring.h>
+#define __KVM_DEV_STRING(name, x) __stringify(name ## _ ## x)
+#define _KVM_DEV_STRING(name, x) __KVM_DEV_STRING(name, x)
+#define KVM_DEV_STRING(x) _KVM_DEV_STRING(KVM_DEV_NAME, x)
+
#ifndef KVM_MAX_VCPU_IDS
#define KVM_MAX_VCPU_IDS KVM_MAX_VCPUS
#endif
diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index b282e3a86769..f37582730ffc 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -4,8 +4,14 @@
#include <linux/tracepoint.h>
+#undef UNPACK_KVM
+#define UNPACK_KVM(name) name
#undef TRACE_SYSTEM
-#define TRACE_SYSTEM kvm
+#define TRACE_SYSTEM UNPACK_KVM(KVM_DEV_NAME)
+#undef TRACE_SYSTEM_VAR
+#define TRACE_SYSTEM_VAR kvm
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE kvm
#define ERSN(x) { KVM_EXIT_##x, "KVM_EXIT_" #x }
diff --git a/virt/kvm/Makefile.kvm b/virt/kvm/Makefile.kvm
index d047d4cf58c9..b39f7b2a5f6e 100644
--- a/virt/kvm/Makefile.kvm
+++ b/virt/kvm/Makefile.kvm
@@ -5,6 +5,11 @@
KVM ?= ../../../virt/kvm
+KVM_DEV_NAME ?= kvm
+KVM_DEV_MINOR ?= KVM_MINOR
+
+ccflags-y +=-DKVM_DEV_NAME=$(KVM_DEV_NAME) -DKVM_DEV_MINOR=$(KVM_DEV_MINOR)
+
kvm-y := $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/binary_stats.o
kvm-$(CONFIG_KVM_VFIO) += $(KVM)/vfio.o
kvm-$(CONFIG_KVM_MMIO) += $(KVM)/coalesced_mmio.o
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index b8aaa96b799b..6b3b6353cb9d 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -21,7 +21,10 @@ static struct kmem_cache *async_pf_cache;
int kvm_async_pf_init(void)
{
- async_pf_cache = KMEM_CACHE(kvm_async_pf, 0);
+ async_pf_cache = kmem_cache_create(KVM_DEV_STRING(async_pf),
+ sizeof(struct kvm_async_pf),
+ __alignof__(struct kvm_async_pf),
+ 0, NULL);
if (!async_pf_cache)
return -ENOMEM;
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 93ad2ebc963f..f43b8b25bc85 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -711,7 +711,8 @@ bool kvm_notify_irqfd_resampler(struct kvm *kvm,
*/
int kvm_irqfd_init(void)
{
- irqfd_cleanup_wq = alloc_workqueue("kvm-irqfd-cleanup", WQ_PERCPU, 0);
+ irqfd_cleanup_wq = alloc_workqueue(__stringify(KVM_DEV_NAME) "-irqfd-cleanup",
+ WQ_PERCPU, 0);
if (!irqfd_cleanup_wq)
return -ENOMEM;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 60e614795a36..f62901b7e23d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -10,6 +10,8 @@
* Yaniv Kamay <yaniv@qumranet.com>
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <kvm/iodev.h>
#include <linux/kvm_host.h>
@@ -1013,7 +1015,7 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, const char *fdname)
mutex_lock(&kvm_debugfs_lock);
dent = debugfs_lookup(dir_name, kvm_debugfs_dir);
if (dent) {
- pr_warn_ratelimited("KVM: debugfs: duplicate directory %s\n", dir_name);
+ pr_warn_ratelimited("debugfs: duplicate directory %s\n", dir_name);
dput(dent);
mutex_unlock(&kvm_debugfs_lock);
return 0;
@@ -4138,9 +4140,9 @@ static struct file_operations kvm_vcpu_fops = {
*/
static int create_vcpu_fd(struct kvm_vcpu *vcpu)
{
- char name[8 + 1 + ITOA_MAX_LEN + 1];
+ char name[sizeof(__stringify(KVM_DEV_NAME) "-vcpu:") + ITOA_MAX_LEN + 1];
- snprintf(name, sizeof(name), "kvm-vcpu:%d", vcpu->vcpu_id);
+ snprintf(name, sizeof(name), __stringify(KVM_DEV_NAME) "-vcpu:%d", vcpu->vcpu_id);
return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
}
@@ -4353,9 +4355,9 @@ static int kvm_vcpu_ioctl_get_stats_fd(struct kvm_vcpu *vcpu)
{
int fd;
struct file *file;
- char name[15 + ITOA_MAX_LEN + 1];
+ char name[sizeof(__stringify(KVM_DEV_NAME) "-vcpu-stats:") + ITOA_MAX_LEN + 1];
- snprintf(name, sizeof(name), "kvm-vcpu-stats:%d", vcpu->vcpu_id);
+ snprintf(name, sizeof(name), __stringify(KVM_DEV_NAME) "-vcpu-stats:%d", vcpu->vcpu_id);
fd = get_unused_fd_flags(O_CLOEXEC);
if (fd < 0)
@@ -5168,7 +5170,7 @@ static int kvm_vm_ioctl_get_stats_fd(struct kvm *kvm)
if (fd < 0)
return fd;
- file = anon_inode_getfile_fmode("kvm-vm-stats",
+ file = anon_inode_getfile_fmode(__stringify(KVM_DEV_NAME) "-vm-stats",
&kvm_vm_stats_fops, kvm, O_RDONLY, FMODE_PREAD);
if (IS_ERR(file)) {
put_unused_fd(fd);
@@ -5545,7 +5547,7 @@ static int kvm_dev_ioctl_create_vm(unsigned long type)
goto put_fd;
}
- file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
+ file = anon_inode_getfile(__stringify(KVM_DEV_NAME) "-vm", &kvm_vm_fops, kvm, O_RDWR);
if (IS_ERR(file)) {
r = PTR_ERR(file);
goto put_kvm;
@@ -5613,8 +5615,8 @@ static struct file_operations kvm_chardev_ops = {
};
static struct miscdevice kvm_dev = {
- KVM_MINOR,
- "kvm",
+ KVM_DEV_MINOR,
+ __stringify(KVM_DEV_NAME),
&kvm_chardev_ops,
};
@@ -5648,7 +5650,7 @@ static int kvm_enable_virtualization_cpu(void)
return 0;
if (kvm_arch_enable_virtualization_cpu()) {
- pr_info("kvm: enabling virtualization on CPU%d failed\n",
+ pr_info("enabling virtualization on CPU%d failed\n",
raw_smp_processor_id());
return -EIO;
}
@@ -5695,7 +5697,7 @@ static void kvm_shutdown(void *data)
* is used for both shutdown and reboot scenarios, i.e. neither name is
* 100% comprehensive.
*/
- pr_info("kvm: exiting hardware virtualization\n");
+ pr_info("exiting hardware virtualization\n");
on_each_cpu(kvm_disable_virtualization_cpu, NULL, 1);
}
@@ -6106,7 +6108,7 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
* attached devices. Otherwise, destroy the caller's device only.
*/
if (!new_bus) {
- pr_err("kvm: failed to shrink bus, removing it completely\n");
+ pr_err("failed to shrink bus, removing it completely\n");
kvm_io_bus_destroy(bus);
return -ENOMEM;
}
@@ -6393,7 +6395,7 @@ static void kvm_init_debug(void)
const struct kvm_stats_desc *pdesc;
int i;
- kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
+ kvm_debugfs_dir = debugfs_create_dir(__stringify(KVM_DEV_NAME), NULL);
for (i = 0; i < kvm_vm_stats_header.num_desc; ++i) {
pdesc = &kvm_vm_stats_desc[i];
@@ -6538,7 +6540,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module)
if (!vcpu_align)
vcpu_align = __alignof__(struct kvm_vcpu);
kvm_vcpu_cache =
- kmem_cache_create_usercopy("kvm_vcpu", vcpu_size, vcpu_align,
+ kmem_cache_create_usercopy(KVM_DEV_STRING(vcpu), vcpu_size, vcpu_align,
SLAB_ACCOUNT,
offsetof(struct kvm_vcpu, arch),
offsetofend(struct kvm_vcpu, stats_id)
@@ -6591,7 +6593,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module)
*/
r = misc_register(&kvm_dev);
if (r) {
- pr_err("kvm: misc device register failed\n");
+ pr_err("misc device register failed\n");
goto err_register;
}
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 02/24] KVM: Move architecture capability Kconfigs to header defines
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 01/24] KVM: Make device name configurable Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 03/24] KVM: Replace CONFIG_KVM_MMIO with KVM_NO_MMIO Steffen Eiden
` (22 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Historically, KVM feature opt-ins and callbacks were configured globally
via Kconfig symbols (CONFIG_HAVE_KVM_* and CONFIG_KVM_*).
With s390 hosting multiple independent KVM implementations within the
same kernel build (native s390 KVM and arm64 on s390), global Kconfig
selections force both implementations to inherit options that only apply
to one of them.
Replace these global Kconfig options with architecture-specific opt-in
defines in <asm/kvm_host.h> and standardize their naming by dropping the
HAVE_ prefix:
- KVM_INVALID_WAKEUPS
- KVM_MSI (formerly HAVE_KVM_MSI)
- KVM_NO_POLL (formerly HAVE_KVM_NO_POLL)
- KVM_READONLY_MEM (formerly HAVE_KVM_READONLY_MEM)
- KVM_VCPU_RUN_PID_CHANGE (formerly HAVE_KVM_VCPU_RUN_PID_CHANGE)
This allows each architecture and guest implementation to configure its
supported capabilities independently in its kvm_host header and eliminates
unnecessary fallback stubs across different KVM targets.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/kvm_host.h | 3 +++
arch/arm64/kvm/Kconfig | 3 ---
arch/loongarch/include/asm/kvm_host.h | 2 ++
arch/loongarch/kvm/Kconfig | 2 --
arch/mips/include/asm/kvm_host.h | 1 +
arch/mips/kvm/Kconfig | 1 -
arch/powerpc/include/asm/kvm_host.h | 3 +++
arch/powerpc/kvm/Kconfig | 1 -
arch/riscv/include/asm/kvm_host.h | 2 ++
arch/riscv/kvm/Kconfig | 2 --
arch/s390/include/asm/kvm_host_s390.h | 3 +++
arch/s390/kvm/Kconfig | 2 --
arch/x86/include/asm/kvm_host.h | 3 +++
arch/x86/kvm/Kconfig | 3 ---
include/linux/kvm_host.h | 18 +++++++++++-------
virt/kvm/Kconfig | 15 ---------------
virt/kvm/kvm_main.c | 4 ++--
17 files changed, 30 insertions(+), 38 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index cd9b9d2462f9..db002e5ac9d4 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -30,6 +30,9 @@
#include <asm/vncr_mapping.h>
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
+#define KVM_MSI
+#define KVM_READONLY_MEM
+#define KVM_VCPU_RUN_PID_CHANGE
#define KVM_HALT_POLL_NS_DEFAULT 500000
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 449154f9a485..7329124deb2f 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -28,12 +28,9 @@ menuconfig KVM
select KVM_VFIO
select HAVE_KVM_DIRTY_RING_ACQ_REL
select NEED_KVM_DIRTY_RING_WITH_BITMAP
- select HAVE_KVM_MSI
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQ_ROUTING
select HAVE_KVM_IRQ_BYPASS
- select HAVE_KVM_READONLY_MEM
- select HAVE_KVM_VCPU_RUN_PID_CHANGE
select SCHED_INFO
select GUEST_PERF_EVENTS if PERF_EVENTS
select KVM_GUEST_MEMFD
diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
index 65d91c3ce313..4cb370a8d09b 100644
--- a/arch/loongarch/include/asm/kvm_host.h
+++ b/arch/loongarch/include/asm/kvm_host.h
@@ -26,6 +26,8 @@
#include <asm/loongarch.h>
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
+#define KVM_MSI
+#define KVM_READONLY_MEM
/* Loongarch KVM register ids */
#define KVM_GET_IOC_CSR_IDX(id) ((id & KVM_CSR_IDX_MASK) >> LOONGARCH_REG_SHIFT)
diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig
index 15da2d88c0c1..a427429a2b05 100644
--- a/arch/loongarch/kvm/Kconfig
+++ b/arch/loongarch/kvm/Kconfig
@@ -23,8 +23,6 @@ config KVM
select HAVE_KVM_DIRTY_RING_ACQ_REL
select HAVE_KVM_IRQ_ROUTING
select HAVE_KVM_IRQCHIP
- select HAVE_KVM_MSI
- select HAVE_KVM_READONLY_MEM
select KVM_COMMON
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select KVM_GENERIC_HARDWARE_ENABLING
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index c14b10821817..8e484bb482ba 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -893,5 +893,6 @@ static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
+#define KVM_READONLY_MEM
#endif /* __MIPS_KVM_HOST_H__ */
diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index b1b9a1d67758..c24b872afbcb 100644
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -24,7 +24,6 @@ config KVM
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select KVM_MMIO
select KVM_GENERIC_HARDWARE_ENABLING
- select HAVE_KVM_READONLY_MEM
help
Support for hosting Guest kernels.
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 2d139c807577..ad7c34e9b227 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -49,6 +49,9 @@
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
+#ifdef CONFIG_KVM_MPIC
+#define KVM_MSI
+#endif
#define KVM_HALT_POLL_NS_DEFAULT 10000 /* 10 us */
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index b6bc2fc86dca..1fae2de8fa68 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -232,7 +232,6 @@ config KVM_MPIC
depends on KVM && PPC_E500
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQ_ROUTING
- select HAVE_KVM_MSI
help
Enable support for emulating MPIC devices inside the
host kernel, rather than relying on userspace to emulate.
diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index a30600579231..23b5560e97ba 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -47,6 +47,8 @@
#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(6)
#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE
+#define KVM_MSI
+#define KVM_READONLY_MEM
#define KVM_HAVE_MMU_RWLOCK
diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig
index ec2cee0a39e0..3cb4f8037300 100644
--- a/arch/riscv/kvm/Kconfig
+++ b/arch/riscv/kvm/Kconfig
@@ -22,8 +22,6 @@ config KVM
depends on RISCV_SBI && MMU
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQ_ROUTING
- select HAVE_KVM_MSI
- select HAVE_KVM_READONLY_MEM
select HAVE_KVM_DIRTY_RING_ACQ_REL
select KVM_COMMON
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
diff --git a/arch/s390/include/asm/kvm_host_s390.h b/arch/s390/include/asm/kvm_host_s390.h
index 9519b8028b10..bd42c84b8b16 100644
--- a/arch/s390/include/asm/kvm_host_s390.h
+++ b/arch/s390/include/asm/kvm_host_s390.h
@@ -34,6 +34,9 @@
#define KVM_INTERNAL_MEM_SLOTS 1
+#define KVM_INVALID_WAKEUPS
+#define KVM_NO_POLL
+
#define KVM_S390_MANAGES_S390_GUEST 1
/*
diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
index 8d3ee17a1bcb..9045ae20fd89 100644
--- a/arch/s390/kvm/Kconfig
+++ b/arch/s390/kvm/Kconfig
@@ -25,8 +25,6 @@ config KVM
select KVM_COMMON
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQ_ROUTING
- select HAVE_KVM_INVALID_WAKEUPS
- select HAVE_KVM_NO_POLL
select KVM_VFIO
select VIRT_XFER_TO_GUEST_WORK
select KVM_MMU_LOCKLESS_AGING
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index e460073ff176..d8f6333de323 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -47,6 +47,9 @@
#define kvm_file_to_kvm_arch x86
#define __KVM_HAVE_ARCH_VCPU_DEBUGFS
+#define KVM_MSI
+#define KVM_NO_POLL
+#define KVM_READONLY_MEM
/*
* CONFIG_KVM_MAX_NR_VCPUS is defined iff CONFIG_KVM!=n, provide a dummy max if
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 538ed1e80332..294684b217bb 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -28,7 +28,6 @@ config KVM_X86
select HAVE_KVM_DIRTY_RING_ACQ_REL
select HAVE_KVM_IRQ_BYPASS
select HAVE_KVM_IRQ_ROUTING
- select HAVE_KVM_READONLY_MEM
select VHOST_TASK
select KVM_ASYNC_PF
select USER_RETURN_NOTIFIER
@@ -37,9 +36,7 @@ config KVM_X86
select PERF_EVENTS
select GUEST_PERF_EVENTS
select PERF_GUEST_MEDIATED_PMU
- select HAVE_KVM_MSI
select HAVE_KVM_CPU_RELAX_INTERCEPT
- select HAVE_KVM_NO_POLL
select VIRT_XFER_TO_GUEST_WORK
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select KVM_VFIO
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 160e3e64ec6d..a0e9cc55a6a4 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -750,7 +750,11 @@ static inline u64 kvm_gmem_get_supported_flags(struct kvm *kvm)
#ifndef kvm_arch_has_readonly_mem
static inline bool kvm_arch_has_readonly_mem(struct kvm *kvm)
{
- return IS_ENABLED(CONFIG_HAVE_KVM_READONLY_MEM);
+#ifdef KVM_READONLY_MEM
+ return true;
+#else
+ return false;
+#endif
}
#endif
@@ -2486,7 +2490,7 @@ void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
struct kvm_kernel_irq_routing_entry *new);
#endif /* CONFIG_HAVE_KVM_IRQ_BYPASS */
-#ifdef CONFIG_HAVE_KVM_INVALID_WAKEUPS
+#ifdef KVM_INVALID_WAKEUPS
/* If we wakeup during the poll time, was it a sucessful poll? */
static inline bool vcpu_valid_wakeup(struct kvm_vcpu *vcpu)
{
@@ -2498,9 +2502,9 @@ static inline bool vcpu_valid_wakeup(struct kvm_vcpu *vcpu)
{
return true;
}
-#endif /* CONFIG_HAVE_KVM_INVALID_WAKEUPS */
+#endif /* KVM_INVALID_WAKEUPS */
-#ifdef CONFIG_HAVE_KVM_NO_POLL
+#ifdef KVM_NO_POLL
/* Callback that tells if we must not poll */
bool kvm_arch_no_poll(struct kvm_vcpu *vcpu);
#else
@@ -2508,18 +2512,18 @@ static inline bool kvm_arch_no_poll(struct kvm_vcpu *vcpu)
{
return false;
}
-#endif /* CONFIG_HAVE_KVM_NO_POLL */
+#endif /* KVM_NO_POLL */
void kvm_arch_guest_memory_reclaimed(struct kvm *kvm);
-#ifdef CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE
+#ifdef KVM_VCPU_RUN_PID_CHANGE
int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu);
#else
static inline int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
{
return 0;
}
-#endif /* CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE */
+#endif /* KVM_VCPU_RUN_PID_CHANGE */
#ifdef CONFIG_VIRT_XFER_TO_GUEST_WORK
static inline void kvm_handle_signal_exit(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index c3c0ee253fc7..f3d7f66746c8 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -50,21 +50,12 @@ config KVM_ASYNC_PF
config KVM_ASYNC_PF_SYNC
bool
-config HAVE_KVM_MSI
- bool
-
-config HAVE_KVM_READONLY_MEM
- bool
-
config HAVE_KVM_CPU_RELAX_INTERCEPT
bool
config KVM_VFIO
bool
-config HAVE_KVM_INVALID_WAKEUPS
- bool
-
config KVM_GENERIC_DIRTYLOG_READ_PROTECT
bool
@@ -79,12 +70,6 @@ config HAVE_KVM_IRQ_BYPASS
tristate
select IRQ_BYPASS_MANAGER
-config HAVE_KVM_VCPU_RUN_PID_CHANGE
- bool
-
-config HAVE_KVM_NO_POLL
- bool
-
config VIRT_XFER_TO_GUEST_WORK
bool
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f62901b7e23d..cd2d752816ab 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4916,7 +4916,7 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
case KVM_CAP_INTERNAL_ERROR_DATA:
-#ifdef CONFIG_HAVE_KVM_MSI
+#ifdef KVM_MSI
case KVM_CAP_SIGNAL_MSI:
#endif
#ifdef CONFIG_HAVE_KVM_IRQCHIP
@@ -5306,7 +5306,7 @@ static long kvm_vm_ioctl(struct file *filp,
r = kvm_ioeventfd(kvm, &data);
break;
}
-#ifdef CONFIG_HAVE_KVM_MSI
+#ifdef KVM_MSI
case KVM_SIGNAL_MSI: {
struct kvm_msi msi;
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 03/24] KVM: Replace CONFIG_KVM_MMIO with KVM_NO_MMIO
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 01/24] KVM: Make device name configurable Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 02/24] KVM: Move architecture capability Kconfigs to header defines Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 04/24] arm64: Use proper include variant Steffen Eiden
` (21 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Defining KVM_MMIO is not flexible enough for multi-KVM systems where one
KVM implements MMIO but others do not. Therefore, remove KVM_MMIO from
the config space and use the macro KVM_NO_MMIO instead.
Define KVM_NO_MMIO for KVM/s390 and for selected KVM/powerpc
configurations.
coalesced_mmio.c is now always compiled&linked. However, for
architectures/configurations defining KVM_NO_MMIO this effectively
collapses to an empty object with no mmio code.
No functional changes.
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/kvm/Kconfig | 1 -
arch/loongarch/kvm/Kconfig | 1 -
arch/mips/kvm/Kconfig | 1 -
arch/powerpc/include/asm/kvm_host.h | 7 +++++++
arch/powerpc/kvm/Kconfig | 4 ----
arch/riscv/kvm/Kconfig | 1 -
arch/s390/include/asm/kvm_host_s390.h | 2 ++
arch/x86/kvm/Kconfig | 1 -
include/linux/kvm_host.h | 2 +-
virt/kvm/Kconfig | 3 ---
virt/kvm/Makefile.kvm | 4 ++--
virt/kvm/coalesced_mmio.c | 4 ++++
virt/kvm/coalesced_mmio.h | 2 +-
virt/kvm/kvm_main.c | 8 ++++----
14 files changed, 21 insertions(+), 20 deletions(-)
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 7329124deb2f..8475f32ad9e6 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -22,7 +22,6 @@ menuconfig KVM
select KVM_COMMON
select KVM_GENERIC_HARDWARE_ENABLING
select HAVE_KVM_CPU_RELAX_INTERCEPT
- select KVM_MMIO
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select VIRT_XFER_TO_GUEST_WORK
select KVM_VFIO
diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig
index a427429a2b05..fd387326d2f2 100644
--- a/arch/loongarch/kvm/Kconfig
+++ b/arch/loongarch/kvm/Kconfig
@@ -26,7 +26,6 @@ config KVM
select KVM_COMMON
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select KVM_GENERIC_HARDWARE_ENABLING
- select KVM_MMIO
select VIRT_XFER_TO_GUEST_WORK
select SCHED_INFO
select GUEST_PERF_EVENTS if PERF_EVENTS
diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index c24b872afbcb..849ce7c7c4df 100644
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -22,7 +22,6 @@ config KVM
select EXPORT_UASM
select KVM_COMMON
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
- select KVM_MMIO
select KVM_GENERIC_HARDWARE_ENABLING
help
Support for hosting Guest kernels.
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index ad7c34e9b227..620f163d65a9 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -29,6 +29,13 @@
#define __KVM_HAVE_ARCH_VCPU_DEBUGFS
+#if !defined(CONFIG_KVM_BOOK3S_32_HANDLER) && \
+ !defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE) && \
+ !defined(CONFIG_KVM_E500V2) && \
+ !defined(CONFIG_KVM_E500MC)
+#define KVM_NO_MMIO
+#endif
+
#define KVM_MAX_VCPUS NR_CPUS
#define KVM_MAX_VCORES NR_CPUS
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index 1fae2de8fa68..cacc22e34afd 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -30,7 +30,6 @@ config KVM_BOOK3S_HANDLER
config KVM_BOOK3S_32_HANDLER
bool
select KVM_BOOK3S_HANDLER
- select KVM_MMIO
config KVM_BOOK3S_64_HANDLER
bool
@@ -38,7 +37,6 @@ config KVM_BOOK3S_64_HANDLER
config KVM_BOOK3S_PR_POSSIBLE
bool
- select KVM_MMIO
config KVM_BOOK3S_HV_POSSIBLE
bool
@@ -201,7 +199,6 @@ config KVM_E500V2
depends on PPC_E500 && !PPC_E500MC
depends on !CONTEXT_TRACKING_USER
select KVM
- select KVM_MMIO
help
Support running unmodified E500 guest kernels in virtual machines on
E500v2 host processors.
@@ -216,7 +213,6 @@ config KVM_E500MC
depends on PPC_E500MC
depends on !CONTEXT_TRACKING_USER
select KVM
- select KVM_MMIO
select KVM_BOOKE_HV
help
Support running unmodified E500MC/E5500/E6500 guest kernels in
diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig
index 3cb4f8037300..2e3c4e6c1cd7 100644
--- a/arch/riscv/kvm/Kconfig
+++ b/arch/riscv/kvm/Kconfig
@@ -26,7 +26,6 @@ config KVM
select KVM_COMMON
select KVM_GENERIC_DIRTYLOG_READ_PROTECT
select KVM_GENERIC_HARDWARE_ENABLING
- select KVM_MMIO
select VIRT_XFER_TO_GUEST_WORK
select SCHED_INFO
select GUEST_PERF_EVENTS if PERF_EVENTS
diff --git a/arch/s390/include/asm/kvm_host_s390.h b/arch/s390/include/asm/kvm_host_s390.h
index bd42c84b8b16..a653b2a73303 100644
--- a/arch/s390/include/asm/kvm_host_s390.h
+++ b/arch/s390/include/asm/kvm_host_s390.h
@@ -39,6 +39,8 @@
#define KVM_S390_MANAGES_S390_GUEST 1
+#define KVM_NO_MMIO
+
/*
* These seem to be used for allocating ->chip in the routing table, which we
* don't use. 1 is as small as we can get to reduce the needed memory. If we
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 294684b217bb..42e79c3c87ff 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -31,7 +31,6 @@ config KVM_X86
select VHOST_TASK
select KVM_ASYNC_PF
select USER_RETURN_NOTIFIER
- select KVM_MMIO
select SCHED_INFO
select PERF_EVENTS
select GUEST_PERF_EVENTS
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index a0e9cc55a6a4..acdde26c739d 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -847,7 +847,7 @@ struct kvm {
struct kvm_vm_stat stat;
struct kvm_arch arch;
refcount_t users_count;
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
spinlock_t ring_lock;
struct list_head coalesced_zones;
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index f3d7f66746c8..24d7dfceb828 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -40,9 +40,6 @@ config NEED_KVM_DIRTY_RING_WITH_BITMAP
bool
depends on HAVE_KVM_DIRTY_RING
-config KVM_MMIO
- bool
-
config KVM_ASYNC_PF
bool
diff --git a/virt/kvm/Makefile.kvm b/virt/kvm/Makefile.kvm
index b39f7b2a5f6e..ec7da5942354 100644
--- a/virt/kvm/Makefile.kvm
+++ b/virt/kvm/Makefile.kvm
@@ -10,9 +10,9 @@ KVM_DEV_MINOR ?= KVM_MINOR
ccflags-y +=-DKVM_DEV_NAME=$(KVM_DEV_NAME) -DKVM_DEV_MINOR=$(KVM_DEV_MINOR)
-kvm-y := $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/binary_stats.o
+kvm-y := $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/binary_stats.o \
+ $(KVM)/coalesced_mmio.o
kvm-$(CONFIG_KVM_VFIO) += $(KVM)/vfio.o
-kvm-$(CONFIG_KVM_MMIO) += $(KVM)/coalesced_mmio.o
kvm-$(CONFIG_KVM_ASYNC_PF) += $(KVM)/async_pf.o
kvm-$(CONFIG_HAVE_KVM_IRQ_ROUTING) += $(KVM)/irqchip.o
kvm-$(CONFIG_HAVE_KVM_DIRTY_RING) += $(KVM)/dirty_ring.o
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index 6b1d90161099..d6cae6855237 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -15,6 +15,8 @@
#include <linux/slab.h>
#include <linux/kvm.h>
+#ifndef KVM_NO_MMIO
+
#include "coalesced_mmio.h"
static inline struct kvm_coalesced_mmio_dev *to_mmio(struct kvm_io_device *dev)
@@ -188,3 +190,5 @@ int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
*/
return 0;
}
+
+#endif /* !KVM_NO_MMIO */
diff --git a/virt/kvm/coalesced_mmio.h b/virt/kvm/coalesced_mmio.h
index 36f84264ed25..bcaa34fce1e8 100644
--- a/virt/kvm/coalesced_mmio.h
+++ b/virt/kvm/coalesced_mmio.h
@@ -11,7 +11,7 @@
*
*/
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
#include <linux/list.h>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index cd2d752816ab..7fe3a3cdc84f 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4086,7 +4086,7 @@ static vm_fault_t kvm_vcpu_fault(struct vm_fault *vmf)
else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
page = virt_to_page(vcpu->arch.pio_data);
#endif
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
#endif
@@ -4927,7 +4927,7 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
case KVM_CAP_ENABLE_CAP_VM:
case KVM_CAP_HALT_POLL:
return 1;
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
case KVM_CAP_COALESCED_MMIO:
return KVM_COALESCED_MMIO_PAGE_OFFSET;
case KVM_CAP_COALESCED_PIO:
@@ -5268,7 +5268,7 @@ static long kvm_vm_ioctl(struct file *filp,
break;
}
#endif
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
case KVM_REGISTER_COALESCED_MMIO: {
struct kvm_coalesced_mmio_zone zone;
@@ -5597,7 +5597,7 @@ static long kvm_dev_ioctl(struct file *filp,
#ifdef CONFIG_X86
r += PAGE_SIZE; /* pio data page */
#endif
-#ifdef CONFIG_KVM_MMIO
+#ifndef KVM_NO_MMIO
r += PAGE_SIZE; /* coalesced mmio ring page */
#endif
break;
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 04/24] arm64: Use proper include variant
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (2 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 03/24] KVM: Replace CONFIG_KVM_MMIO with KVM_NO_MMIO Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 05/24] arm64: ptrace: Use constants for compat register numbers Steffen Eiden
` (20 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Use <> for including the sysreg header as it is not discoverable from
the current directory.
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/sysreg.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 7aa08d59d494..4bfdac9401bd 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -173,7 +173,7 @@
* come from here. The header relies on the definition of sys_reg()
* earlier in this file.
*/
-#include "asm/sysreg-defs.h"
+#include <asm/sysreg-defs.h>
/*
* System registers, organised loosely by encoding but grouped together
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 05/24] arm64: ptrace: Use constants for compat register numbers
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (3 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 04/24] arm64: Use proper include variant Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation Steffen Eiden
` (19 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Define an enum to determine the register number for the mapping from
AArch32 and AArch64 registers. This allows for a more flexible use of
the register mappings.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/ptrace.h | 60 ++++++++++++++++++++++-----------
1 file changed, 41 insertions(+), 19 deletions(-)
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index f7dc5fb9427d..49a83a0636b9 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -102,26 +102,48 @@
#define COMPAT_USER_SZ 296
/* Architecturally defined mapping between AArch32 and AArch64 registers */
+enum {
+ __compat_fp = 11,
+ __compat_sp = 13,
+ __compat_lr = 14,
+ __compat_sp_hyp = 15,
+ __compat_lr_irq = 16,
+ __compat_sp_irq = 17,
+ __compat_lr_svc = 18,
+ __compat_sp_svc = 19,
+ __compat_lr_abt = 20,
+ __compat_sp_abt = 21,
+ __compat_lr_und = 22,
+ __compat_sp_und = 23,
+ __compat_r8_fiq = 24,
+ __compat_r9_fiq = 25,
+ __compat_r10_fiq = 26,
+ __compat_r11_fiq = 27,
+ __compat_r12_fiq = 28,
+ __compat_sp_fiq = 29,
+ __compat_lr_fiq = 30,
+};
+
#define compat_usr(x) regs[(x)]
-#define compat_fp regs[11]
-#define compat_sp regs[13]
-#define compat_lr regs[14]
-#define compat_sp_hyp regs[15]
-#define compat_lr_irq regs[16]
-#define compat_sp_irq regs[17]
-#define compat_lr_svc regs[18]
-#define compat_sp_svc regs[19]
-#define compat_lr_abt regs[20]
-#define compat_sp_abt regs[21]
-#define compat_lr_und regs[22]
-#define compat_sp_und regs[23]
-#define compat_r8_fiq regs[24]
-#define compat_r9_fiq regs[25]
-#define compat_r10_fiq regs[26]
-#define compat_r11_fiq regs[27]
-#define compat_r12_fiq regs[28]
-#define compat_sp_fiq regs[29]
-#define compat_lr_fiq regs[30]
+#define compat_fp regs[__compat_fp]
+#define compat_sp regs[__compat_sp]
+#define compat_lr regs[__compat_lr]
+#define compat_sp_hyp regs[__compat_sp_hyp]
+#define compat_lr_irq regs[__compat_lr_irq]
+#define compat_sp_irq regs[__compat_sp_irq]
+#define compat_lr_svc regs[__compat_lr_svc]
+#define compat_sp_svc regs[__compat_sp_svc]
+#define compat_lr_abt regs[__compat_lr_abt]
+#define compat_sp_abt regs[__compat_sp_abt]
+#define compat_lr_und regs[__compat_lr_und]
+#define compat_sp_und regs[__compat_sp_und]
+#define compat_r8_fiq regs[__compat_r8_fiq]
+#define compat_r9_fiq regs[__compat_r9_fiq]
+#define compat_r10_fiq regs[__compat_r10_fiq]
+#define compat_r11_fiq regs[__compat_r11_fiq]
+#define compat_r12_fiq regs[__compat_r12_fiq]
+#define compat_sp_fiq regs[__compat_sp_fiq]
+#define compat_lr_fiq regs[__compat_lr_fiq]
static inline unsigned long compat_psr_to_pstate(const unsigned long psr)
{
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (4 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 05/24] arm64: ptrace: Use constants for compat register numbers Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 07/24] KVM: arm64: Access elements of vcpu_gp_regs individually Steffen Eiden
` (18 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Convert SPSR_EL{1, 2, 12} to automatic register generation as per
DDI0601.
No functional change.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/sysreg.h | 3 --
arch/arm64/tools/sysreg | 51 +++++++++++++++++++++++++++++++++
2 files changed, 51 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 4bfdac9401bd..1aa601c95188 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -295,7 +295,6 @@
#define SYS_APGAKEYLO_EL1 sys_reg(3, 0, 2, 3, 0)
#define SYS_APGAKEYHI_EL1 sys_reg(3, 0, 2, 3, 1)
-#define SYS_SPSR_EL1 sys_reg(3, 0, 4, 0, 0)
#define SYS_ELR_EL1 sys_reg(3, 0, 4, 0, 1)
#define SYS_ICC_PMR_EL1 sys_reg(3, 0, 4, 6, 0)
@@ -518,7 +517,6 @@
#define SYS_VTTBR_EL2 sys_reg(3, 4, 2, 1, 0)
#define SYS_HAFGRTR_EL2 sys_reg(3, 4, 3, 1, 6)
-#define SYS_SPSR_EL2 sys_reg(3, 4, 4, 0, 0)
#define SYS_ELR_EL2 sys_reg(3, 4, 4, 0, 1)
#define SYS_SP_EL1 sys_reg(3, 4, 4, 1, 0)
#define SYS_SPSR_irq sys_reg(3, 4, 4, 3, 0)
@@ -604,7 +602,6 @@
#define SYS_BRBCR_EL12 sys_reg(2, 5, 9, 0, 0)
#define SYS_TTBR0_EL12 sys_reg(3, 5, 2, 0, 0)
#define SYS_TTBR1_EL12 sys_reg(3, 5, 2, 0, 1)
-#define SYS_SPSR_EL12 sys_reg(3, 5, 4, 0, 0)
#define SYS_ELR_EL12 sys_reg(3, 5, 4, 0, 1)
#define SYS_AFSR0_EL12 sys_reg(3, 5, 5, 1, 0)
#define SYS_AFSR1_EL12 sys_reg(3, 5, 5, 1, 1)
diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
index e2d37ee221b8..893b5f9df575 100644
--- a/arch/arm64/tools/sysreg
+++ b/arch/arm64/tools/sysreg
@@ -401,6 +401,57 @@ Res0 3:1
Field 0 SO
EndSysreg
+SysregFields SPSR_ELx
+Res0 63:37
+Field 36 UINJ
+Field 35 PACM
+Field 34 EXLOCK
+Res0 33
+Field 32 PM
+Field 31 N
+Field 30 Z
+Field 29 C
+Field 28 V
+Res0 27:26
+Field 25 TCO
+Field 24 DIT
+Field 23 UAO
+Field 22 PAN
+Field 21 SS
+Field 20 IL
+Res0 19:14
+Field 13 ALLINT
+Field 12 SSBS
+Field 11:10 BTYPE
+Field 9 D
+Field 8 A
+Field 7 I
+Field 6 F
+Res0 5
+Field 4 M4
+Enum 3:0 M
+ 0b0000 EL0
+ 0b0100 EL1t
+ 0b0101 EL1h
+ 0b1000 EL2t
+ 0b1001 EL2h
+ 0b1100 EL3t
+ 0b1101 EL3h
+EndEnum
+EndSysregFields
+
+Sysreg SPSR_EL1 3 0 4 0 0
+Fields SPSR_ELx
+EndSysreg
+
+Sysreg SPSR_EL2 3 4 4 0 0
+Fields SPSR_ELx
+EndSysreg
+
+Sysreg SPSR_EL12 3 5 4 0 0
+Mapping SPSR_EL1
+EndSysreg
+
Sysreg ID_PFR0_EL1 3 0 0 1 0
Res0 63:32
UnsignedEnum 31:28 RAS
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 07/24] KVM: arm64: Access elements of vcpu_gp_regs individually
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (5 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 08/24] KVM: arm64: Use accessor functions for core regs Steffen Eiden
` (17 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
While for arm64 the members of vcpu_gp_regs are allocated continuous
this is not necessarily true for other architectures implementing ARM.
Let vcpu_gp_regs() no longer return the address of the user_pt_regs in
the vcpu context but the address of the gp-register array field in the
user_pt_reg struct. Note, this change semantically excludes pc from the
GPRs.
No functional change.
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/kvm_emulate.h | 14 ++++++++------
arch/arm64/include/asm/kvm_host.h | 2 +-
arch/arm64/kvm/guest.c | 2 +-
arch/arm64/kvm/hyp/exception.c | 4 ++--
arch/arm64/kvm/hyp/include/hyp/adjust_pc.h | 4 ++--
arch/arm64/kvm/hyp/include/hyp/switch.h | 4 ++--
6 files changed, 16 insertions(+), 14 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index a3c1928bdf74..8603766c1b4d 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -133,12 +133,12 @@ static inline void vcpu_set_vsesr(struct kvm_vcpu *vcpu, u64 vsesr)
static __always_inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
{
- return (unsigned long *)&vcpu_gp_regs(vcpu)->pc;
+ return (unsigned long *)&vcpu->arch.ctxt.regs.pc;
}
static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
{
- return (unsigned long *)&vcpu_gp_regs(vcpu)->pstate;
+ return (unsigned long *)&vcpu->arch.ctxt.regs.pstate;
}
static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
@@ -167,14 +167,14 @@ static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
static __always_inline unsigned long vcpu_get_reg(const struct kvm_vcpu *vcpu,
u8 reg_num)
{
- return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)->regs[reg_num];
+ return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)[reg_num];
}
static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
unsigned long val)
{
if (reg_num != 31)
- vcpu_gp_regs(vcpu)->regs[reg_num] = val;
+ vcpu_gp_regs(vcpu)[reg_num] = val;
}
static inline bool vcpu_is_el2_ctxt(const struct kvm_cpu_context *ctxt)
@@ -750,13 +750,15 @@ static inline void kvm_reset_vcpu_core(struct kvm_vcpu *vcpu)
pstate = VCPU_RESET_PSTATE_EL1;
/* Reset core registers */
- memset(vcpu_gp_regs(vcpu), 0, sizeof(*vcpu_gp_regs(vcpu)));
+ memset(vcpu_gp_regs(vcpu), 0, sizeof(vcpu_gp_regs(vcpu)));
+ *vcpu_pc(vcpu) = 0;
+ vcpu->arch.ctxt.regs.sp = 0;
memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs));
vcpu->arch.ctxt.spsr_abt = 0;
vcpu->arch.ctxt.spsr_und = 0;
vcpu->arch.ctxt.spsr_irq = 0;
vcpu->arch.ctxt.spsr_fiq = 0;
- vcpu_gp_regs(vcpu)->pstate = pstate;
+ *vcpu_cpsr(vcpu) = pstate;
}
/* PSCI reset handling for a vcpu. */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index db002e5ac9d4..99c6cb260309 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -1161,7 +1161,7 @@ struct kvm_vcpu_arch {
#define vcpu_clear_on_unsupported_cpu(vcpu) \
vcpu_clear_flag(vcpu, ON_UNSUPPORTED_CPU)
-#define vcpu_gp_regs(v) (&(v)->arch.ctxt.regs)
+#define vcpu_gp_regs(v) ((v)->arch.ctxt.regs.regs)
/*
* Only use __vcpu_sys_reg/ctxt_sys_reg if you know you want the
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index b01d6622b872..81d850d5a328 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -134,7 +134,7 @@ static void *core_reg_addr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
KVM_REG_ARM_CORE_REG(regs.regs[30]):
off -= KVM_REG_ARM_CORE_REG(regs.regs[0]);
off /= 2;
- return &vcpu->arch.ctxt.regs.regs[off];
+ return &vcpu_gp_regs(vcpu)[off];
case KVM_REG_ARM_CORE_REG(regs.sp):
return &vcpu->arch.ctxt.regs.sp;
diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c
index 754e2dc1df54..0640c9ccaa3c 100644
--- a/arch/arm64/kvm/hyp/exception.c
+++ b/arch/arm64/kvm/hyp/exception.c
@@ -276,12 +276,12 @@ static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset)
switch(mode) {
case PSR_AA32_MODE_ABT:
__vcpu_write_spsr_abt(vcpu, host_spsr_to_spsr32(spsr));
- vcpu_gp_regs(vcpu)->compat_lr_abt = return_address;
+ vcpu_gp_regs(vcpu)[__compat_lr_abt] = return_address;
break;
case PSR_AA32_MODE_UND:
__vcpu_write_spsr_und(vcpu, host_spsr_to_spsr32(spsr));
- vcpu_gp_regs(vcpu)->compat_lr_und = return_address;
+ vcpu_gp_regs(vcpu)[__compat_lr_und] = return_address;
break;
}
diff --git a/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h b/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h
index 4fdfeabefeb4..a049983bd5c3 100644
--- a/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h
+++ b/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h
@@ -33,11 +33,11 @@ static inline void kvm_skip_instr(struct kvm_vcpu *vcpu)
static inline void __kvm_skip_instr(struct kvm_vcpu *vcpu)
{
*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
- vcpu_gp_regs(vcpu)->pstate = read_sysreg_el2(SYS_SPSR);
+ *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR);
kvm_skip_instr(vcpu);
- write_sysreg_el2(vcpu_gp_regs(vcpu)->pstate, SYS_SPSR);
+ write_sysreg_el2(*vcpu_cpsr(vcpu), SYS_SPSR);
write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
}
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 1ce7130e2549..a2a054fec2e2 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -470,7 +470,7 @@ static inline bool kvm_hyp_handle_mops(struct kvm_vcpu *vcpu, u64 *exit_code)
u64 spsr;
*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
- arm64_mops_reset_regs(vcpu_gp_regs(vcpu), vcpu->arch.fault.esr_el2);
+ arm64_mops_reset_regs(&vcpu->arch.ctxt.regs, vcpu->arch.fault.esr_el2);
write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
/*
@@ -902,7 +902,7 @@ static inline void synchronize_vcpu_pstate(struct kvm_vcpu *vcpu)
/*
* Check for the conditions of Cortex-A510's #2077057. When these occur
* SPSR_EL2 can't be trusted, but isn't needed either as it is
- * unchanged from the value in vcpu_gp_regs(vcpu)->pstate.
+ * unchanged from the value in vcpu_cpsr(vcpu).
* Are we single-stepping the guest, and took a PAC exception from the
* active-not-pending state?
*/
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 08/24] KVM: arm64: Use accessor functions for core regs
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (6 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 07/24] KVM: arm64: Access elements of vcpu_gp_regs individually Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 09/24] arm64: Prepare sharing arm64 headers with s390 Steffen Eiden
` (16 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Instead of accessing the value directly use accessor functions that
abstract the actual location of the register values. Add a helper
function to reset fpsimd registers. Enables other KVM implementations to
reuse this code.
No functional changes.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/kvm_emulate.h | 34 ++++++++++++++++++++++++++--
arch/arm64/kvm/guest.c | 14 ++++++------
2 files changed, 39 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 8603766c1b4d..b31d50bdf59e 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -141,6 +141,31 @@ static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
return (unsigned long *)&vcpu->arch.ctxt.regs.pstate;
}
+static __always_inline unsigned long *vcpu_sp_el0(struct kvm_vcpu *vcpu)
+{
+ return (unsigned long *)&vcpu->arch.ctxt.regs.sp;
+}
+
+static __always_inline u64 *vcpu_sp_el1(struct kvm_vcpu *vcpu)
+{
+ return __ctxt_sys_reg(&vcpu->arch.ctxt, SP_EL1);
+}
+
+static __always_inline __u128 *vcpu_vreg(struct kvm_vcpu *vcpu, int n)
+{
+ return &vcpu->arch.ctxt.fp_regs.vregs[n];
+}
+
+static __always_inline __u32 *vcpu_fpsr(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.ctxt.fp_regs.fpsr;
+}
+
+static __always_inline __u32 *vcpu_fpcr(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.ctxt.fp_regs.fpcr;
+}
+
static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
{
return !!(*vcpu_cpsr(vcpu) & PSR_MODE32_BIT);
@@ -737,6 +762,11 @@ static inline void vcpu_set_hcrx(struct kvm_vcpu *vcpu)
}
}
+static inline void kvm_reset_fpsimd(struct kvm_vcpu *vcpu)
+{
+ memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs));
+}
+
/* Reset a vcpu's core registers. */
static inline void kvm_reset_vcpu_core(struct kvm_vcpu *vcpu)
{
@@ -752,8 +782,8 @@ static inline void kvm_reset_vcpu_core(struct kvm_vcpu *vcpu)
/* Reset core registers */
memset(vcpu_gp_regs(vcpu), 0, sizeof(vcpu_gp_regs(vcpu)));
*vcpu_pc(vcpu) = 0;
- vcpu->arch.ctxt.regs.sp = 0;
- memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs));
+ *vcpu_sp_el0(vcpu) = 0;
+ kvm_reset_fpsimd(vcpu);
vcpu->arch.ctxt.spsr_abt = 0;
vcpu->arch.ctxt.spsr_und = 0;
vcpu->arch.ctxt.spsr_irq = 0;
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 81d850d5a328..773f6c8e5026 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -137,16 +137,16 @@ static void *core_reg_addr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return &vcpu_gp_regs(vcpu)[off];
case KVM_REG_ARM_CORE_REG(regs.sp):
- return &vcpu->arch.ctxt.regs.sp;
+ return vcpu_sp_el0(vcpu);
case KVM_REG_ARM_CORE_REG(regs.pc):
- return &vcpu->arch.ctxt.regs.pc;
+ return vcpu_pc(vcpu);
case KVM_REG_ARM_CORE_REG(regs.pstate):
- return &vcpu->arch.ctxt.regs.pstate;
+ return vcpu_cpsr(vcpu);
case KVM_REG_ARM_CORE_REG(sp_el1):
- return __ctxt_sys_reg(&vcpu->arch.ctxt, SP_EL1);
+ return vcpu_sp_el1(vcpu);
case KVM_REG_ARM_CORE_REG(elr_el1):
return __ctxt_sys_reg(&vcpu->arch.ctxt, ELR_EL1);
@@ -170,13 +170,13 @@ static void *core_reg_addr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
off -= KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]);
off /= 4;
- return &vcpu->arch.ctxt.fp_regs.vregs[off];
+ return vcpu_vreg(vcpu, off);
case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
- return &vcpu->arch.ctxt.fp_regs.fpsr;
+ return vcpu_fpsr(vcpu);
case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
- return &vcpu->arch.ctxt.fp_regs.fpcr;
+ return vcpu_fpcr(vcpu);
default:
return NULL;
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 09/24] arm64: Prepare sharing arm64 headers with s390
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (7 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 08/24] KVM: arm64: Use accessor functions for core regs Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 10/24] arm64: Share " Steffen Eiden
` (15 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Prepare the sharing of arm64 headers with s390 by moving definitions
inside headers to reduce the number of shared markers. Clean up includes
to further streamline the sharing of headers.
No functional change.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/include/asm/esr.h | 4 +-
arch/arm64/include/asm/kvm_arm.h | 5 +-
arch/arm64/include/asm/kvm_host.h | 102 ++++++++++++++++--------------
arch/arm64/include/asm/sysreg.h | 2 +-
4 files changed, 59 insertions(+), 54 deletions(-)
diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h
index f816f5d77f1a..da085c83b57e 100644
--- a/arch/arm64/include/asm/esr.h
+++ b/arch/arm64/include/asm/esr.h
@@ -7,7 +7,7 @@
#ifndef __ASM_ESR_H
#define __ASM_ESR_H
-#include <asm/memory.h>
+#include <asm/brk-imm.h>
#include <asm/sysreg.h>
#define ESR_ELx_EC_UNKNOWN UL(0x00)
@@ -435,7 +435,7 @@
#define ESR_ELx_IT_GCSPOPX 7
#ifndef __ASSEMBLER__
-#include <asm/types.h>
+#include <linux/types.h>
static inline unsigned long esr_brk_comment(unsigned long esr)
{
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 4bfbd827c5aa..57edd8437200 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -7,10 +7,11 @@
#ifndef __ARM64_KVM_ARM_H__
#define __ARM64_KVM_ARM_H__
+#include <linux/const.h>
+#include <linux/bits.h>
+#include <linux/types.h>
#include <asm/esr.h>
-#include <asm/memory.h>
#include <asm/sysreg.h>
-#include <asm/types.h>
/*
* Because I'm terribly lazy and that repainting the whole of the KVM
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 99c6cb260309..55966decfeb6 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -59,6 +59,46 @@
#define KVM_REQ_MAP_L1_VNCR_EL2 KVM_ARCH_REQ(10)
#define KVM_REQ_VGIC_PROCESS_UPDATE KVM_ARCH_REQ(11)
+/* Bit indices for kvm_arch::flags */
+enum {
+ /*
+ * If we encounter a data abort without valid instruction syndrome
+ * information, report this to user space. User space can (and
+ * should) opt in to this feature if KVM_CAP_ARM_NISV_TO_USER is
+ * supported.
+ */
+ KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
+ /* Memory Tagging Extension enabled for the guest */
+ KVM_ARCH_FLAG_MTE_ENABLED,
+ /* At least one vCPU has ran in the VM */
+ KVM_ARCH_FLAG_HAS_RAN_ONCE,
+ /* The vCPU feature set for the VM is configured */
+ KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED,
+ /* PSCI SYSTEM_SUSPEND enabled for the guest */
+ KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED,
+ /* VM counter offset */
+ KVM_ARCH_FLAG_VM_COUNTER_OFFSET,
+ /* Timer PPIs made immutable */
+ KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE,
+ /* Initial ID reg values loaded */
+ KVM_ARCH_FLAG_ID_REGS_INITIALIZED,
+ /* Fine-Grained UNDEF initialised */
+ KVM_ARCH_FLAG_FGU_INITIALIZED,
+ /* SVE exposed to guest */
+ KVM_ARCH_FLAG_GUEST_HAS_SVE,
+ /* MIDR_EL1, REVIDR_EL1, and AIDR_EL1 are writable from userspace */
+ KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS,
+ /* Unhandled SEAs are taken to userspace */
+ KVM_ARCH_FLAG_EXIT_SEA,
+};
+
+struct vcpu_reset_state {
+ unsigned long pc;
+ unsigned long r0;
+ bool be;
+ bool reset;
+};
+
#define KVM_DIRTY_LOG_MANUAL_CAPS (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | \
KVM_DIRTY_LOG_INITIALLY_SET)
@@ -341,35 +381,6 @@ struct kvm_arch {
/* Protects VM-scoped configuration data */
struct mutex config_lock;
- /*
- * If we encounter a data abort without valid instruction syndrome
- * information, report this to user space. User space can (and
- * should) opt in to this feature if KVM_CAP_ARM_NISV_TO_USER is
- * supported.
- */
-#define KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER 0
- /* Memory Tagging Extension enabled for the guest */
-#define KVM_ARCH_FLAG_MTE_ENABLED 1
- /* At least one vCPU has ran in the VM */
-#define KVM_ARCH_FLAG_HAS_RAN_ONCE 2
- /* The vCPU feature set for the VM is configured */
-#define KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED 3
- /* PSCI SYSTEM_SUSPEND enabled for the guest */
-#define KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED 4
- /* VM counter offset */
-#define KVM_ARCH_FLAG_VM_COUNTER_OFFSET 5
- /* Timer PPIs made immutable */
-#define KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE 6
- /* Initial ID reg values loaded */
-#define KVM_ARCH_FLAG_ID_REGS_INITIALIZED 7
- /* Fine-Grained UNDEF initialised */
-#define KVM_ARCH_FLAG_FGU_INITIALIZED 8
- /* SVE exposed to guest */
-#define KVM_ARCH_FLAG_GUEST_HAS_SVE 9
- /* MIDR_EL1, REVIDR_EL1, and AIDR_EL1 are writable from userspace */
-#define KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS 10
- /* Unhandled SEAs are taken to userspace */
-#define KVM_ARCH_FLAG_EXIT_SEA 11
unsigned long flags;
/* VM-wide vCPU feature set */
@@ -838,13 +849,6 @@ extern s64 kvm_nvhe_sym(hyp_physvirt_offset);
extern u64 kvm_nvhe_sym(hyp_cpu_logical_map)[NR_CPUS];
#define hyp_cpu_logical_map CHOOSE_NVHE_SYM(hyp_cpu_logical_map)
-struct vcpu_reset_state {
- unsigned long pc;
- unsigned long r0;
- bool be;
- bool reset;
-};
-
struct vncr_tlb;
struct kvm_vcpu_arch {
@@ -1049,6 +1053,11 @@ struct kvm_vcpu_arch {
/* pKVM VCPU setup completed */
#define VCPU_PKVM_FINALIZED __vcpu_single_flag(cflags, BIT(2))
+int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature);
+bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu);
+
+#define kvm_arm_vcpu_sve_finalized(vcpu) vcpu_get_flag(vcpu, VCPU_SVE_FINALIZED)
+
/* Exception pending */
#define PENDING_EXCEPTION __vcpu_single_flag(iflags, BIT(0))
/*
@@ -1242,14 +1251,6 @@ struct kvm_vcpu_stat {
u64 exits;
};
-unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
-int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
-int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
-int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
-
-unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu);
-int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices);
-
int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events);
@@ -1328,6 +1329,14 @@ int __init populate_nv_trap_config(void);
void kvm_calculate_traps(struct kvm_vcpu *vcpu);
+unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
+int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
+int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+
+unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu);
+int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices);
+
/* MMIO helpers */
void kvm_mmio_write_buf(void *buf, unsigned int len, unsigned long data);
unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len);
@@ -1511,11 +1520,6 @@ struct kvm *kvm_arch_alloc_vm(void);
#define vcpu_is_protected(vcpu) kvm_vm_is_protected((vcpu)->kvm)
-int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature);
-bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu);
-
-#define kvm_arm_vcpu_sve_finalized(vcpu) vcpu_get_flag(vcpu, VCPU_SVE_FINALIZED)
-
#define kvm_has_mte(kvm) \
(system_supports_mte() && \
test_bit(KVM_ARCH_FLAG_MTE_ENABLED, &(kvm)->arch.flags))
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 1aa601c95188..ab205f9db94a 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -1263,6 +1263,6 @@
FIELD_PREP(reg##_##field##_MASK, \
SYS_FIELD_VALUE(reg, field, val))
-#endif
+#endif /* __ASSEMBLER__ */
#endif /* __ASM_SYSREG_H */
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 10/24] arm64: Share arm64 headers with s390
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (8 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 09/24] arm64: Prepare sharing arm64 headers with s390 Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 11/24] KVM: arm64: Share arm64 code " Steffen Eiden
` (14 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Allow sharing of arm64 headers with s390 by marking the shared regions
or by adding a comment that the whole file is shared.
The shared regions are marked with:
#if ARM64_S390_COMMON == 1
/* insert shared definitions here */
#endif /* ARM64_S390_COMMON == 1 */
The preprocessor symbol ARM64_S390_COMMON is always defined to 1 for any
arm64 build. s390 later will generate its own view of arm64 headers
based on the content inside the #if/#endif block.
No functional change.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/Makefile | 3 +++
arch/arm64/include/asm/brk-imm.h | 1 +
arch/arm64/include/asm/esr.h | 1 +
arch/arm64/include/asm/kvm_arm.h | 1 +
arch/arm64/include/asm/kvm_emulate.h | 18 ++++++++++++++++++
arch/arm64/include/asm/kvm_host.h | 13 +++++++++++++
arch/arm64/include/asm/ptrace.h | 4 ++++
arch/arm64/include/asm/sysreg.h | 15 +++++++++++++++
8 files changed, 56 insertions(+)
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 6b005c8fef70..a2ed76cfdc0a 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -45,6 +45,9 @@ KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) \
KBUILD_CFLAGS += $(call cc-disable-warning, psabi)
KBUILD_AFLAGS += $(compat_vdso)
+# Enable all code shared to s390
+KBUILD_CPPFLAGS += -DARM64_S390_COMMON=1
+
ifeq ($(call rustc-min-version, 108500),y)
KBUILD_RUSTFLAGS += --target=aarch64-unknown-none-softfloat
else
diff --git a/arch/arm64/include/asm/brk-imm.h b/arch/arm64/include/asm/brk-imm.h
index beb42c62b6ac..dd2d153dc0d8 100644
--- a/arch/arm64/include/asm/brk-imm.h
+++ b/arch/arm64/include/asm/brk-imm.h
@@ -2,6 +2,7 @@
/*
* Copyright (C) 2012 ARM Ltd.
*/
+/* Whole file is shared with s390 */
#ifndef __ASM_BRK_IMM_H
#define __ASM_BRK_IMM_H
diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h
index da085c83b57e..2cb73bde7346 100644
--- a/arch/arm64/include/asm/esr.h
+++ b/arch/arm64/include/asm/esr.h
@@ -3,6 +3,7 @@
* Copyright (C) 2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
+/* Whole file is shared with s390 */
#ifndef __ASM_ESR_H
#define __ASM_ESR_H
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 57edd8437200..678f0daed445 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -3,6 +3,7 @@
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
+/* Whole file is shared with s390 */
#ifndef __ARM64_KVM_ARM_H__
#define __ARM64_KVM_ARM_H__
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index b31d50bdf59e..e19d61f5ccd8 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -44,6 +44,7 @@ enum exception_type {
bool kvm_condition_valid32(const struct kvm_vcpu *vcpu);
void kvm_skip_instr32(struct kvm_vcpu *vcpu);
+#if ARM64_S390_COMMON == 1
void kvm_inject_undefined(struct kvm_vcpu *vcpu);
void kvm_inject_sync(struct kvm_vcpu *vcpu, u64 esr);
int kvm_inject_serror_esr(struct kvm_vcpu *vcpu, u64 esr);
@@ -75,6 +76,8 @@ static inline int kvm_inject_serror(struct kvm_vcpu *vcpu)
void kvm_vcpu_wfi(struct kvm_vcpu *vcpu);
+#endif /* ARM64_S390_COMMON == 1 */
+
void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu);
int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2);
int kvm_inject_nested_irq(struct kvm_vcpu *vcpu);
@@ -184,6 +187,7 @@ static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
}
+#if ARM64_S390_COMMON == 1
/*
* vcpu_get_reg and vcpu_set_reg should always be passed a register number
* coming from a read of ESR_EL2. Otherwise, it may give the wrong result on
@@ -202,6 +206,8 @@ static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
vcpu_gp_regs(vcpu)[reg_num] = val;
}
+#endif /* ARM64_S390_COMMON == 1 */
+
static inline bool vcpu_is_el2_ctxt(const struct kvm_cpu_context *ctxt)
{
switch (ctxt->regs.pstate & (PSR_MODE32_BIT | PSR_MODE_MASK)) {
@@ -404,6 +410,7 @@ static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
return vcpu->arch.fault.disr_el1;
}
+#if ARM64_S390_COMMON == 1
static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
{
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_xVC_IMM_MASK;
@@ -481,6 +488,8 @@ static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC;
}
+#endif /* ARM64_S390_COMMON == 1 */
+
static inline
bool kvm_vcpu_trap_is_permission_fault(const struct kvm_vcpu *vcpu)
{
@@ -521,6 +530,7 @@ static __always_inline int kvm_vcpu_sys_get_rt(struct kvm_vcpu *vcpu)
return ESR_ELx_SYS64_ISS_RT(esr);
}
+#if ARM64_S390_COMMON == 1
static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
{
if (kvm_vcpu_abt_iss1tw(vcpu)) {
@@ -545,6 +555,8 @@ static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
return kvm_vcpu_dabt_iswrite(vcpu);
}
+#endif /* ARM64_S390_COMMON == 1 */
+
static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
{
return __vcpu_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
@@ -586,6 +598,7 @@ static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
return vcpu_read_sys_reg(vcpu, r) & bit;
}
+#if ARM64_S390_COMMON == 1
static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
unsigned long data,
unsigned int len)
@@ -661,6 +674,8 @@ static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu)
vcpu_set_flag((v), e); \
} while (0)
+#endif /* ARM64_S390_COMMON == 1 */
+
/*
* Returns a 'sanitised' view of CPTR_EL2, translating from nVHE to the VHE
* format if E2H isn't set.
@@ -767,6 +782,7 @@ static inline void kvm_reset_fpsimd(struct kvm_vcpu *vcpu)
memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs));
}
+#if ARM64_S390_COMMON == 1
/* Reset a vcpu's core registers. */
static inline void kvm_reset_vcpu_core(struct kvm_vcpu *vcpu)
{
@@ -791,6 +807,8 @@ static inline void kvm_reset_vcpu_core(struct kvm_vcpu *vcpu)
*vcpu_cpsr(vcpu) = pstate;
}
+#endif /* ARM64_S390_COMMON == 1 */
+
/* PSCI reset handling for a vcpu. */
static inline void kvm_reset_vcpu_psci(struct kvm_vcpu *vcpu,
struct vcpu_reset_state *reset_state)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 55966decfeb6..b61d92c8c0ca 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -42,6 +42,7 @@
#define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS
+#if ARM64_S390_COMMON == 1
#define KVM_VCPU_MAX_FEATURES 10
#define KVM_VCPU_VALID_FEATURES (BIT(KVM_VCPU_MAX_FEATURES) - 1)
@@ -99,6 +100,8 @@ struct vcpu_reset_state {
bool reset;
};
+#endif /* ARM64_S390_COMMON == 1 */
+
#define KVM_DIRTY_LOG_MANUAL_CAPS (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | \
KVM_DIRTY_LOG_INITIALLY_SET)
@@ -958,6 +961,7 @@ struct kvm_vcpu_arch {
pid_t pid;
};
+#if ARM64_S390_COMMON == 1
/*
* Each 'flag' is composed of a comma-separated triplet:
*
@@ -1116,6 +1120,8 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu);
/* KVM is currently emulating an L2 to L1 exception */
#define IN_NESTED_EXCEPTION __vcpu_single_flag(sflags, BIT(9))
+#endif /* ARM64_S390_COMMON == 1 */
+
#define vcpu_sve_max_vq(vcpu) sve_vq_from_vl((vcpu)->arch.sve_max_vl)
#define vcpu_sve_zcr_elx(vcpu) \
@@ -1329,6 +1335,7 @@ int __init populate_nv_trap_config(void);
void kvm_calculate_traps(struct kvm_vcpu *vcpu);
+#if ARM64_S390_COMMON == 1
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
@@ -1344,6 +1351,8 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len);
int kvm_handle_mmio_return(struct kvm_vcpu *vcpu);
int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa);
+#endif /* ARM64_S390_COMMON == 1 */
+
/*
* Returns true if a Performance Monitoring Interrupt (PMI), a.k.a. perf event,
* arrived in guest context. For arm64, any event that arrives while a vCPU is
@@ -1536,11 +1545,15 @@ static inline bool __vcpu_has_feature(const struct kvm_arch *ka, int feature)
return test_bit(feature, ka->vcpu_features);
}
+#if ARM64_S390_COMMON == 1
+
#define kvm_vcpu_has_feature(k, f) __vcpu_has_feature(&(k)->arch, (f))
#define vcpu_has_feature(v, f) __vcpu_has_feature(&(v)->kvm->arch, (f))
#define kvm_vcpu_initialized(v) vcpu_get_flag(v, VCPU_INITIALIZED)
+#endif /* ARM64_S390_COMMON == 1 */
+
int kvm_trng_call(struct kvm_vcpu *vcpu);
#ifdef CONFIG_KVM
extern phys_addr_t hyp_mem_base;
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index 49a83a0636b9..4d88ed5cc425 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -26,6 +26,8 @@
#define GIC_PRIO_PSR_I_SET GICV3_PRIO_PSR_I_SET
+#if ARM64_S390_COMMON == 1
+
/* Additional SPSR bits not exposed in the UABI */
#define PSR_MODE_THREAD_BIT (1 << 0)
#define PSR_IL_BIT (1 << 20)
@@ -66,6 +68,8 @@
#define PSR_AA32_IT_MASK 0x0600fc00 /* If-Then execution state mask */
#define PSR_AA32_GE_MASK 0x000f0000
+#endif /* ARM64_S390_COMMON == 1 */
+
#ifdef CONFIG_CPU_BIG_ENDIAN
#define PSR_AA32_ENDSTATE PSR_AA32_E_BIT
#else
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index ab205f9db94a..779e6587ed0f 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -16,6 +16,8 @@
#include <asm/gpr-num.h>
+#if ARM64_S390_COMMON == 1
+
/*
* ARMv8 ARM reserves the following encoding for system registers:
* (Ref: ARMv8 ARM, Section: "System instruction class encoding overview",
@@ -50,6 +52,8 @@
#define sys_reg_CRm(id) (((id) >> CRm_shift) & CRm_mask)
#define sys_reg_Op2(id) (((id) >> Op2_shift) & Op2_mask)
+#endif /* ARM64_S390_COMMON == 1 */
+
#ifndef CONFIG_BROKEN_GAS_INST
#ifdef __ASSEMBLER__
@@ -123,6 +127,8 @@
#define GSB_SYS_BARRIER_INSN __SYS_BARRIER_INSN(1, 0, 12, 0, 0, 31)
#define GSB_ACK_BARRIER_INSN __SYS_BARRIER_INSN(1, 0, 12, 0, 1, 31)
+#if ARM64_S390_COMMON == 1
+
/* Data cache zero operations */
#define SYS_DC_ISW sys_insn(1, 0, 7, 6, 2)
#define SYS_DC_IGSW sys_insn(1, 0, 7, 6, 4)
@@ -832,6 +838,8 @@
#define SCTLR_ELx_A (BIT(1))
#define SCTLR_ELx_M (BIT(0))
+#endif /* ARM64_S390_COMMON == 1 */
+
#ifdef CONFIG_CPU_BIG_ENDIAN
#define ENDIAN_SET_EL2 SCTLR_ELx_EE
#else
@@ -866,6 +874,7 @@
SCTLR_EL1_LSMAOE | SCTLR_EL1_nTLSMD | SCTLR_EL1_EIS | \
SCTLR_EL1_TSCXT | SCTLR_EL1_EOS)
+#if ARM64_S390_COMMON == 1
/* MAIR_ELx memory attributes (used by Linux) */
#define MAIR_ATTR_DEVICE_nGnRnE UL(0x00)
#define MAIR_ATTR_DEVICE_nGnRE UL(0x04)
@@ -1102,6 +1111,8 @@
#define GICV5_GICR_CDNMIA_TYPE_MASK GENMASK_ULL(31, 29)
#define GICV5_GICR_CDNMIA_ID_MASK GENMASK_ULL(23, 0)
+#endif /* ARM64_S390_COMMON == 1 */
+
#define gicr_insn(insn) read_sysreg_s(GICV5_OP_GICR_##insn)
#define gic_insn(v, insn) write_sysreg_s(v, GICV5_OP_GIC_##insn)
@@ -1251,6 +1262,8 @@
par; \
})
+#if ARM64_S390_COMMON == 1
+
#define SYS_FIELD_VALUE(reg, field, val) reg##_##field##_##val
#define SYS_FIELD_GET(reg, field, val) \
@@ -1263,6 +1276,8 @@
FIELD_PREP(reg##_##field##_MASK, \
SYS_FIELD_VALUE(reg, field, val))
+#endif /* ARM64_S390_COMMON == 1 */
+
#endif /* __ASSEMBLER__ */
#endif /* __ASM_SYSREG_H */
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 11/24] KVM: arm64: Share arm64 code with s390
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (9 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 10/24] arm64: Share " Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 12/24] s390/Kconfig: remove PCI dependency from HAS_IOMEM Steffen Eiden
` (13 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Mark functions that s390 can use to implement arm on s390 as shared
functions.
No functional change.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/arm64/kvm/arm.c | 3 +++
arch/arm64/kvm/guest.c | 6 ++++++
arch/arm64/kvm/mmio.c | 2 ++
3 files changed, 11 insertions(+)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 0576c2022ef5..b94879a0b409 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1607,6 +1607,7 @@ static unsigned long system_supported_vcpu_features(void)
return features;
}
+#if ARM64_S390_COMMON == 1
static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
const struct kvm_vcpu_init *init)
{
@@ -1660,6 +1661,8 @@ static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
KVM_VCPU_MAX_FEATURES);
}
+#endif /* ARM64_S390_COMMON == 1 */
+
static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 773f6c8e5026..0259c515997b 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -62,6 +62,7 @@ const struct kvm_stats_header kvm_vcpu_stats_header = {
sizeof(kvm_vcpu_stats_desc),
};
+#if ARM64_S390_COMMON == 1
static bool core_reg_offset_is_vreg(u64 off)
{
return off >= KVM_REG_ARM_CORE_REG(fp_regs.vregs) &&
@@ -306,6 +307,8 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return err;
}
+#endif /* ARM64_S390_COMMON == 1 */
+
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
@@ -543,6 +546,7 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
return -EINVAL;
}
+#if ARM64_S390_COMMON == 1
static int copy_core_reg_indices(const struct kvm_vcpu *vcpu,
u64 __user *uindices)
{
@@ -591,6 +595,8 @@ static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
return copy_core_reg_indices(vcpu, NULL);
}
+#endif /* ARM64_S390_COMMON == 1 */
+
static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
const unsigned int slices = vcpu_sve_slices(vcpu);
diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c
index d1c3a352d5a2..3eaf687eae07 100644
--- a/arch/arm64/kvm/mmio.c
+++ b/arch/arm64/kvm/mmio.c
@@ -10,6 +10,7 @@
#include "trace.h"
+#if ARM64_S390_COMMON == 1
void kvm_mmio_write_buf(void *buf, unsigned int len, unsigned long data)
{
void *datap = NULL;
@@ -258,3 +259,4 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
run->exit_reason = KVM_EXIT_MMIO;
return 0;
}
+#endif /* ARM64_S390_COMMON == 1 */
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 12/24] s390/Kconfig: remove PCI dependency from HAS_IOMEM
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (10 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 11/24] KVM: arm64: Share arm64 code " Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 13/24] KVM: s390: Use dedicated function for migration mode Steffen Eiden
` (12 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
HAS_IOMEM was defined as def_bool PCI on s390, making it false on kernels
built without PCI support. This made sense until now as the IOMEM code
was only required if PCI was enabled. This will change as KVM will
require IOMEM in the future. To simplify the config space, turn
HAS_IOMEM on unconditionally by default.
All other architectures either do not override HAS_IOMEM or set it
unconditionally. s390 was the only architecture where HAS_IOMEM could be
false on a real system.
Since HAS_IOMEM=y now causes kernel/iomem.o and lib/devres.o to be built
unconditionally, ioremap()/iounmap() must always be available.
Select GENERIC_IOREMAP unconditionally to provide the generic
implementations for the PCI=n case.
Previously GENERIC_IOREMAP was conditioned on CONFIG_PCI in lockstep
with HAS_IOMEM, so mm/ioremap.c was never built without PCI. Therefore,
guard the PCI override macros ioremap_prot, iounmap, and ioremap_wc with
CONFIG_PCI.
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/Kconfig | 5 +----
arch/s390/include/asm/io.h | 12 ++++++------
2 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 4b51bc6e8948..5a01fbd8e32b 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -181,7 +181,7 @@ config S390
select GENERIC_ENTRY
select GENERIC_GETTIMEOFDAY
select GENERIC_SMP_IDLE_THREAD
- select GENERIC_IOREMAP if PCI
+ select GENERIC_IOREMAP
select GLOB
select HAVE_ALIGNED_STRUCT_PAGE
select HAVE_ARCH_AUDITSYSCALL
@@ -768,9 +768,6 @@ config PCI_NR_FUNCTIONS
endif # PCI
-config HAS_IOMEM
- def_bool PCI
-
config CHSC_SCH
def_tristate m
prompt "Support for CHSC subchannels"
diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h
index faddb9aef3b8..ef0490edeccd 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -27,14 +27,8 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
/*
* I/O memory mapping functions.
*/
-#define ioremap_prot ioremap_prot
-#define iounmap iounmap
-
#define _PAGE_IOREMAP pgprot_val(PAGE_KERNEL)
-#define ioremap_wc(addr, size) \
- ioremap_prot((addr), (size), pgprot_writecombine(PAGE_KERNEL))
-
static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
{
return NULL;
@@ -46,6 +40,12 @@ static inline void ioport_unmap(void __iomem *p)
#ifdef CONFIG_PCI
+#define ioremap_prot ioremap_prot
+#define iounmap iounmap
+
+#define ioremap_wc(addr, size) \
+ ioremap_prot((addr), (size), pgprot_writecombine(PAGE_KERNEL))
+
/*
* s390 needs a private implementation of pci_iomap since ioremap with its
* offset parameter isn't sufficient. That's because BAR spaces are not
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 13/24] KVM: s390: Use dedicated function for migration mode
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (11 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 12/24] s390/Kconfig: remove PCI dependency from HAS_IOMEM Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 14/24] s390/tools: Use arm64 headers Steffen Eiden
` (11 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Use kvm_s390_is_migration_mode() instead of kvm.arch->migration_mode.
The function is independent of the actual kvm_arch implementation which
is different for the second parallel KVM module..
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/gmap/kvm_mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/s390/kvm/gmap/kvm_mmu.c b/arch/s390/kvm/gmap/kvm_mmu.c
index c2ffb5e59ec6..24e618f77be1 100644
--- a/arch/s390/kvm/gmap/kvm_mmu.c
+++ b/arch/s390/kvm/gmap/kvm_mmu.c
@@ -76,7 +76,7 @@ int s390_kvm_mmu_prepare_memory_region(struct kvm *kvm,
return -EINVAL;
}
- if (kvm->arch.migration_mode) {
+ if (kvm_s390_is_migration_mode(kvm)) {
/*
* Turn off migration mode when:
* - userspace creates a new memslot with dirty logging off,
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 14/24] s390/tools: Use arm64 headers
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (12 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 13/24] KVM: s390: Use dedicated function for migration mode Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-10-01 10:25 ` Hendrik Brueckner
2026-09-30 17:34 ` [PATCH v9 15/24] KVM: s390: Use arm64 code Steffen Eiden
` (10 subsequent siblings)
24 siblings, 1 reply; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Introduce a flexible system for sharing ARM64 headers with s390 KVM.
Selected arm64 headers or snippet of headers will be reachable by s390
code through asm/header.h.
Add copy-arm64h.awk that detects ARM64_S390_COMMON markers and extracts
marked section into a generated header consumable by s390. Falls back to
full file copy when no markers are found.
Transform copied includes by replacing '#include <asm/...>' with
'#include <arm64/...>' and similar for uapi headers to ensure
correct path resolution on s390 and allow for a clear separation of s390
asm headers and arm64 asm headers.
Integrate this extraction into the s390/kapi target, conditional on
CONFIG_KVM.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/include/uapi/Kbuild | 6 ++
arch/s390/tools/Makefile | 6 +-
arch/s390/tools/Makefile.arm64h | 55 ++++++++++++++++++
arch/s390/tools/copy-arm64h-full.awk | 50 +++++++++++++++++
arch/s390/tools/copy-arm64h.awk | 83 ++++++++++++++++++++++++++++
5 files changed, 199 insertions(+), 1 deletion(-)
create mode 100644 arch/s390/include/uapi/Kbuild
create mode 100644 arch/s390/tools/Makefile.arm64h
create mode 100644 arch/s390/tools/copy-arm64h-full.awk
create mode 100644 arch/s390/tools/copy-arm64h.awk
diff --git a/arch/s390/include/uapi/Kbuild b/arch/s390/include/uapi/Kbuild
new file mode 100644
index 000000000000..81dcaaf42c40
--- /dev/null
+++ b/arch/s390/include/uapi/Kbuild
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# The ARM64 uapi headers under generated/uapi/arm64/ are private copies used
+# internally by the s390 KVM ARM64 implementation. They contain #line
+# directives and rewritten include paths and must not be shipped to userspace.
+no-export-headers += arm64/%
diff --git a/arch/s390/tools/Makefile b/arch/s390/tools/Makefile
index f2862364fb42..d0aa7e076bad 100644
--- a/arch/s390/tools/Makefile
+++ b/arch/s390/tools/Makefile
@@ -3,12 +3,16 @@
# Makefile for s390 specific build tools
#
+include $(srctree)/arch/s390/tools/Makefile.arm64h
+
kapi := arch/$(ARCH)/include/generated/asm
kapi-hdrs-y := $(kapi)/facility-defs.h $(kapi)/dis-defs.h
+kapi-hdrs-$(CONFIG_KVM) += $(ARM64_TARGETS)
+
PHONY += kapi
-kapi: $(kapi-hdrs-y)
+kapi: $(kapi-hdrs-y) $(kapi-hdrs-m)
hostprogs += gen_facilities
hostprogs += gen_opcode_table
diff --git a/arch/s390/tools/Makefile.arm64h b/arch/s390/tools/Makefile.arm64h
new file mode 100644
index 000000000000..f3f8e9d9bdd8
--- /dev/null
+++ b/arch/s390/tools/Makefile.arm64h
@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Share ARM64 headers with s390 KVM
+#
+
+arm64api := $(objtree)/arch/$(ARCH)/include/generated/arm64
+arm64uapi := $(objtree)/arch/$(ARCH)/include/generated/uapi/arm64
+
+# List of ARM64 headers to share with s390 KVM
+# Format: [uapi:]header.h or header-gen.h
+#
+# * header.h - from arch/arm64/include/asm/ to arm64/
+# * uapi:header.h - from arch/arm64/include/uapi/asm/ to uapi/arm64/
+# * header-gen.h - generated as header-gen.h from ARM64 header header.h
+# If a header contains partial markers (#if ARM64_S390_COMMON == 1) only this part will be copied.
+# If the file does not contain any markers the whole file will be copied.
+ARM64_SHARED_HEADERS := \
+ brk-imm.h \
+ esr.h \
+ kvm_arm.h \
+ kvm_emulate-gen.h \
+ kvm_host.h \
+ ptrace-gen.h \
+ sysreg-gen.h \
+ uapi:hwcap.h \
+ uapi:kvm.h \
+ uapi:ptrace.h \
+ uapi:sve_context.h
+
+filechk_gen_arm_hdr = \
+ $(AWK) -f $(src)/copy-arm64h.awk $< || \
+ $(AWK) -f $(src)/copy-arm64h-full.awk $< || \
+ { echo "Error: Unbalanced ARM64_S390_COMMON markers in $<" >&2; exit 1; }
+
+arm64-type = $(firstword $(subst :, ,$(1)))
+arm64-base = $(or $(word 2,$(subst :, ,$(1))),$(1))
+arm64-src-base = $(patsubst %-gen.h,%.h,$(call arm64-base,$(1)))
+
+arm64-src = $(srctree)/arch/arm64/include/$(if $(filter uapi,$(call arm64-type,$(1))),uapi/)asm/$(call arm64-src-base,$(1))
+arm64-dst = $(if $(filter uapi,$(call arm64-type,$(1))),$(arm64uapi),$(arm64api))/$(call arm64-base,$(1))
+
+$(foreach hdr,$(ARM64_SHARED_HEADERS),\
+ $(eval $(call arm64-dst,$(hdr)): $(call arm64-src,$(hdr)) $(src)/copy-arm64h.awk $(src)/copy-arm64h-full.awk FORCE))
+
+ARM64_TARGETS := $(sort $(foreach hdr,$(ARM64_SHARED_HEADERS),$(call arm64-dst,$(hdr))))
+$(ARM64_TARGETS):
+ $(call filechk,gen_arm_hdr)
+
+filechk_gen_sysreg_arm64 = \
+ $(AWK) -f $(srctree)/arch/arm64/tools/gen-sysreg.awk $(srctree)/arch/arm64/tools/sysreg
+
+$(arm64api)/sysreg-defs.h: $(srctree)/arch/arm64/tools/gen-sysreg.awk $(srctree)/arch/arm64/tools/sysreg FORCE
+ $(call filechk,gen_sysreg_arm64)
+
+ARM64_TARGETS += $(arm64api)/sysreg-defs.h
diff --git a/arch/s390/tools/copy-arm64h-full.awk b/arch/s390/tools/copy-arm64h-full.awk
new file mode 100644
index 000000000000..ad7bb98dc4a6
--- /dev/null
+++ b/arch/s390/tools/copy-arm64h-full.awk
@@ -0,0 +1,50 @@
+#!/usr/bin/awk -f
+# SPDX-License-Identifier: GPL-2.0
+#
+# Process entire ARM64 headers for sharing with s390 KVM
+#
+# Usage: copy-arm64h-full.awk <input_file>
+#
+# This processes the entire file (unlike copy-arm64h.awk which only extracts marked sections)
+
+BEGIN {
+ max_guard_line = 25
+ guard_found = 0
+ header_added = 0
+}
+
+# Find and process the include guard in the first few lines
+NR <= max_guard_line && !guard_found && /^#ifndef [A-Z_0-9]+$/ {
+ guard_name = $2
+ guard_found = 1
+ print "/* This header was copied from " FILENAME " */"
+ print ""
+ # Map subsequent lines back to the original ARM64 source file so that
+ # compiler diagnostics point there rather than at the generated copy.
+ print "#line " NR " \"" FILENAME "\""
+ print
+ header_added = 1
+ next
+}
+
+# Transform include directives
+/^#include <uapi\/asm\// {
+ sub(/<uapi\/asm\//, "<uapi/arm64/")
+ print
+ next
+}
+
+/^#include <asm\// {
+ sub(/<asm\//, "<arm64/")
+ print
+ next
+}
+
+/ARM64_S390_COMMON/ {
+ exit 1
+}
+
+# Pass through all other lines
+{
+ print
+}
diff --git a/arch/s390/tools/copy-arm64h.awk b/arch/s390/tools/copy-arm64h.awk
new file mode 100644
index 000000000000..9a338d71bba2
--- /dev/null
+++ b/arch/s390/tools/copy-arm64h.awk
@@ -0,0 +1,83 @@
+#!/usr/bin/awk -f
+# SPDX-License-Identifier: GPL-2.0
+#
+# Extract marked sections from ARM64 headers for sharing with s390 KVM
+#
+# Usage: copy-arm64h.awk <input_file>
+#
+# Extracts all sections between start/end markers. If no markers found, signals for fallback.
+BEGIN {
+ # Constants
+ start_pattern = "^#if ARM64_S390_COMMON == 1$"
+ end_pattern = "^#endif \\/\\* ARM64_S390_COMMON == 1 \\*\\/$"
+ max_guard_line = 25
+
+ # State variables
+ copying = found_marker = error = 0
+ guard_name = ""
+ file_header_done = 0
+ depth = 0
+}
+
+NR <= max_guard_line && !guard_name && /^#ifndef [A-Za-z0-9_]+$/ {
+ guard_name = $2
+ next
+}
+
+NR > max_guard_line && !guard_name && !file_header_done {
+ print "error: no include guard found in first " max_guard_line " lines" > "/dev/stderr"
+ file_header_done = 1
+ error = 1; exit
+}
+
+$0 ~ start_pattern {
+ if (copying) { error = 1; exit }
+ if (!found_marker) {
+ print "/*"
+ print " * This header was automatically generated from " FILENAME
+ print " * Do not modify this file directly."
+ print " */"
+ print "#ifndef " guard_name
+ print "#define " guard_name
+ print ""
+ }
+ depth = copying= found_marker = 1
+ # Map subsequent lines back to the original ARM64 source file so that
+ # compiler diagnostics point there rather than at the generated copy.
+ print "#line " (NR + 1) " \"" FILENAME "\""
+ next
+}
+
+guard_name && !found_marker {
+ next
+}
+
+$0 ~ /^[ \t]*#[ \t]*endif/ {
+ depth--
+ if (depth == 0) {
+ if ($0 ~ end_pattern ) {
+ copying = 0
+ next
+ }
+ error = 1; exit
+ }
+}
+
+/ARM64_S390_COMMON/ { error = 1; exit }
+
+copying {
+ if ($0 ~ /^[ \t]*#[ \t]*if(def|ndef)?([ \t]|$)/) depth++
+ gsub(/#include <asm\//, "#include <arm64/")
+ gsub(/#include <uapi\/asm\//, "#include <uapi/arm64/")
+ print
+ next
+}
+
+END {
+ if (error) exit 1
+ if (found_marker) {
+ print ""
+ print "#endif /* " guard_name " */"
+ }
+ exit !found_marker || copying
+}
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 14/24] s390/tools: Use arm64 headers
2026-09-30 17:34 ` [PATCH v9 14/24] s390/tools: Use arm64 headers Steffen Eiden
@ 2026-10-01 10:25 ` Hendrik Brueckner
0 siblings, 0 replies; 36+ messages in thread
From: Hendrik Brueckner @ 2026-10-01 10:25 UTC (permalink / raw)
To: Steffen Eiden
Cc: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390,
Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
On Wed, Sep 30, 2026 at 07:34:29PM +0200, Steffen Eiden wrote:
> Introduce a flexible system for sharing ARM64 headers with s390 KVM.
> Selected arm64 headers or snippet of headers will be reachable by s390
> code through asm/header.h.
>
> Add copy-arm64h.awk that detects ARM64_S390_COMMON markers and extracts
> marked section into a generated header consumable by s390. Falls back to
> full file copy when no markers are found.
>
> Transform copied includes by replacing '#include <asm/...>' with
> '#include <arm64/...>' and similar for uapi headers to ensure
> correct path resolution on s390 and allow for a clear separation of s390
> asm headers and arm64 asm headers.
>
> Integrate this extraction into the s390/kapi target, conditional on
> CONFIG_KVM.
>
> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
> ---
> arch/s390/include/uapi/Kbuild | 6 ++
> arch/s390/tools/Makefile | 6 +-
> arch/s390/tools/Makefile.arm64h | 55 ++++++++++++++++++
> arch/s390/tools/copy-arm64h-full.awk | 50 +++++++++++++++++
> arch/s390/tools/copy-arm64h.awk | 83 ++++++++++++++++++++++++++++
Thanks for the updates.
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
^ permalink raw reply [flat|nested] 36+ messages in thread
* [PATCH v9 15/24] KVM: s390: Use arm64 code
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (13 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 14/24] s390/tools: Use arm64 headers Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 16/24] s390: Introduce Start Arm Execution instruction Steffen Eiden
` (9 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Add the infrastructure to extract KVM/arm64 code into s390 at build
time similar to the arm64 header sharing. Add copy-arm64c.awk that
detects ARM64_S390_COMMON markers and extracts marked section into an
.inc file that can be consumed by arm on s390 host code. If no marker is
found make will fail.
To ensure that no code is consumed twice by accident a guard is added
during file generation. A s390 C file wanting to consume such an inc
file must first define __INCL_GEN_ARM_FILE otherwise the inc file will
emit a compile error.
Example:
#define __INCL_GEN_ARM_FILE
#include <generated/arm.inc>
#undef __INCL_GEN_ARM_FILE
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/arm64/.gitignore | 2 +
arch/s390/kvm/arm64/Makefile.gen | 28 ++++++++++
arch/s390/kvm/arm64/copy-arm64c.awk | 82 +++++++++++++++++++++++++++++
3 files changed, 112 insertions(+)
create mode 100644 arch/s390/kvm/arm64/.gitignore
create mode 100644 arch/s390/kvm/arm64/Makefile.gen
create mode 100644 arch/s390/kvm/arm64/copy-arm64c.awk
diff --git a/arch/s390/kvm/arm64/.gitignore b/arch/s390/kvm/arm64/.gitignore
new file mode 100644
index 000000000000..bd9d90694676
--- /dev/null
+++ b/arch/s390/kvm/arm64/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+generated/*
diff --git a/arch/s390/kvm/arm64/Makefile.gen b/arch/s390/kvm/arm64/Makefile.gen
new file mode 100644
index 000000000000..9c33b068fab5
--- /dev/null
+++ b/arch/s390/kvm/arm64/Makefile.gen
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Extracts ARM64 marked sections to .inc files that are included by main source
+# files
+
+# List of ARM64 C files to extract
+ARM64_CFILES := \
+ arm.c \
+ guest.c \
+ mmio.c
+
+quiet_cmd_extract_inc = GEN $@
+ cmd_extract_inc = mkdir -p $(dir $@); \
+ $(AWK) -f $(src)/copy-arm64c.awk $< > $@ || \
+ { echo "Error: No or unbalanced ARM64_S390_COMMON markers in $<" >&2; rm -f $@; exit 1; }
+
+ARM64_INC_FILES := $(foreach cfile,$(ARM64_CFILES),generated/$(basename $(cfile)).inc)
+
+$(addprefix $(obj)/,$(ARM64_INC_FILES)): $(obj)/generated/%.inc: $(srctree)/arch/arm64/kvm/%.c $(src)/copy-arm64c.awk FORCE
+ $(call if_changed,extract_inc)
+
+targets += $(ARM64_INC_FILES)
+clean-files += generated/*.inc
+
+$(foreach cfile,$(basename $(ARM64_CFILES)),\
+ $(eval $(obj)/$(cfile).o $(obj)/$(cfile).i $(obj)/$(cfile).s \
+ $(obj)/$(cfile).ll $(obj)/$(cfile).lst: \
+ $(obj)/generated/$(cfile).inc))
diff --git a/arch/s390/kvm/arm64/copy-arm64c.awk b/arch/s390/kvm/arm64/copy-arm64c.awk
new file mode 100644
index 000000000000..640a7bcb7e23
--- /dev/null
+++ b/arch/s390/kvm/arm64/copy-arm64c.awk
@@ -0,0 +1,82 @@
+#!/usr/bin/awk -f
+# SPDX-License-Identifier: GPL-2.0
+#
+# Extract marked sections from ARM64 C files for sharing with s390 KVM
+#
+# Usage: copy-arm64c.awk <input_file>
+#
+# Extracts all sections between start/end markers. If no markers found, signals failure.
+
+BEGIN {
+ # Constants
+ start_pattern = "^#if ARM64_S390_COMMON == 1$"
+ end_pattern = "^#endif /\\* ARM64_S390_COMMON == 1 \\*/$"
+
+ # State variables
+ copying = found_marker = 0
+ file_header_done = 0
+ depth = 0
+}
+
+!file_header_done {
+ if (/^\/\*/ || /^\/\/ SPDX-License-Identifier:/) {
+ print
+ next
+ }
+ if (/[[:space:]]\*([[:space:]]|$)/) {
+ print
+ next
+ }
+ if (/\*\//) {
+ print " *"
+ } else {
+ print "/*"
+ }
+
+ print " * This file was automatically generated from " FILENAME
+ print " * Do not modify this file directly."
+ print " */"
+ print ""
+ print "#ifndef __INCL_GEN_ARM_FILE"
+ print "#error do not include this file directly."
+ print "#endif /* __INCL_GEN_ARM_FILE */"
+ print "#undef __INCL_GEN_ARM_FILE"
+ print ""
+
+ file_header_done = 1
+}
+
+$0 ~ start_pattern {
+ if (copying) { error = 1; exit }
+ depth = copying = found_marker = 1
+ # Map subsequent lines back to the original ARM64 source file so that
+ # compiler diagnostics point there rather than at the generated copy.
+ print "#line " (NR + 1) " \"" FILENAME "\""
+ next
+}
+
+copying && /^[ \t]*#[ \t]*if(def|ndef)?([ \t]|$)/ { depth++ }
+
+$0 ~ /^[ \t]*#[ \t]*endif/ {
+ depth--
+ if (depth == 0) {
+ if ($0 ~ end_pattern) {
+ copying = 0
+ next
+ }
+ error = 1; exit
+ }
+}
+
+/ARM64_S390_COMMON/ { error = 1; exit }
+
+copying {
+ gsub(/#include <asm\//, "#include <arm64/")
+ gsub(/#include <uapi\/asm\//, "#include <uapi/arm64/")
+ print
+ next
+}
+
+END {
+ exit error || !found_marker || copying
+}
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 16/24] s390: Introduce Start Arm Execution instruction
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (14 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 15/24] KVM: s390: Use arm64 code Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 17/24] KVM: s390: arm64: Introduce host definitions Steffen Eiden
` (8 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
The Start Arm Execution (SAE) instruction is the centerpiece for
executing arm64 (KVM) guests on s390. Its purpose is, similar to SIE, to
enable accelerated execution of arm64 virtual machines. SAE expects the
physical address of a control block as the only argument.
The host is responsible to save & restore
- GPRs 0-13
- access registers 0-15
- breaking event register (BEAR)
- vector/floating point registers
between SAE executions to guarantee host consistency.
GPRs and BEAR are saved and restored in the asm functions. The other
registers are handled within C code. Access registers are handled in a
later patch and SVEs will be handled when they are introduced in a
future series. Most arm64 registers are handled by a satellite block
called save_area. Some registers, frequently used by hypervisors, are
placed into the SAE control block itself.
Enlighten asm/kvm_host_types.h for the new header variant. The new
header is chosen instead of asm/kvm_host_s390_types.h if KVM_S390_ARM64
is defined.
Co-developed-by: Andreas Grapentin <gra@linux.ibm.com>
Signed-off-by: Andreas Grapentin <gra@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/include/asm/asm-prototypes.h | 1 +
arch/s390/include/asm/kvm_host_arm64_types.h | 124 +++++++++++++++++++
arch/s390/include/asm/kvm_host_types.h | 4 +
arch/s390/include/asm/sae.h | 49 ++++++++
arch/s390/include/asm/stacktrace.h | 5 +
arch/s390/kernel/asm-offsets.c | 1 +
arch/s390/kernel/entry.S | 22 ++++
arch/s390/tools/opcodes.txt | 3 +
8 files changed, 209 insertions(+)
create mode 100644 arch/s390/include/asm/kvm_host_arm64_types.h
create mode 100644 arch/s390/include/asm/sae.h
diff --git a/arch/s390/include/asm/asm-prototypes.h b/arch/s390/include/asm/asm-prototypes.h
index d4da4436d02b..faa2afb259a1 100644
--- a/arch/s390/include/asm/asm-prototypes.h
+++ b/arch/s390/include/asm/asm-prototypes.h
@@ -6,6 +6,7 @@
#include <asm/bug.h>
#include <asm/fpu.h>
#include <asm/nospec-branch.h>
+#include <asm/sae.h>
#include <asm-generic/asm-prototypes.h>
#endif /* _ASM_S390_PROTOTYPES_H */
diff --git a/arch/s390/include/asm/kvm_host_arm64_types.h b/arch/s390/include/asm/kvm_host_arm64_types.h
new file mode 100644
index 000000000000..8783a66d3029
--- /dev/null
+++ b/arch/s390/include/asm/kvm_host_arm64_types.h
@@ -0,0 +1,124 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASM_KVM_HOST_ARM64_TYPES_H
+#define ASM_KVM_HOST_ARM64_TYPES_H
+
+#include <linux/types.h>
+#include <linux/kvm_types.h>
+#include <linux/compiler_attributes.h>
+#include <asm/page.h>
+#include <asm/fault.h>
+
+struct kvm_sae_block {
+ u64 _0000[16]; /* 0x0000 */
+#define SAE_ICPTR_SPURIOUS 0x00
+#define SAE_ICPTR_VALIDITY 0x01
+#define SAE_ICPTR_HOST_ACCESS_EXCEPTION 0x02
+#define SAE_ICPTR_SYNCHRONOUS_EXCEPTION 0x03
+#define SAE_ICPTR_TIMER 0x04
+#define SAE_ICPTR_PE_INTERCOMM 0x05
+#define SAE_ICPTR_GUEST_ADDRESS_SIZE 0x06
+#define SAE_ICPTR_STOP 0x07
+#define SAE_ICPTR_MIO_ADDRESS 0x08
+#define SAE_ICPTR_PMU 0x09
+#define SAE_ICPTR_MAINTENANCE 0x0a
+ u8 icptr; /* 0x0080 */
+ u8 _0081[7]; /* 0x0081 */
+ u64 scad; /* 0x0088 */
+ u64 _0090[16]; /* 0x0090 */
+ u32 cntp_ctl; /* 0x0110 */
+ u32 cntv_ctl; /* 0x0114 */
+ u8 irq_ctl; /* 0x0118 */
+ u8 _0119[7]; /* 0x0119 */
+ struct {
+ u64 ich_hcr_el2; /* 0x0120 */
+ u64 ich_vmcr_el2; /* 0x0128 */
+ u64 ich_ap0r0_el2; /* 0x0130 */
+ u64 ich_ap1r0_el2; /* 0x0138 */
+ u64 _0140[2]; /* 0x0140 */
+ u64 ich_lrn_el2[4]; /* 0x0150 */
+ u64 _0170[4]; /* 0x0170 */
+ } ic_regs;
+ u64 _0190[12]; /* 0x0190 */
+ u64 contextidr_el1; /* 0x01f0 */
+ u32 wip; /* 0x01f8 */
+ u32 _01fc; /* 0x01fc */
+#define SAE_SD_FORMAT_0 0x00
+ u8 sdf; /* 0x0200 */
+ u8 _0201[7]; /* 0x0201 */
+ u64 mso; /* 0x0208 */
+ u64 msl; /* 0x0210 */
+ u64 hbasce; /* 0x0218 */
+ u64 _0220; /* 0x0220 */
+ u64 gpto; /* 0x0228 */
+ u64 ic; /* 0x0230 */
+ u64 ec; /* 0x0238 */
+ u64 save_area; /* 0x0240 */
+ u64 _0248[7]; /* 0x0248 */
+ u8 _0280[6]; /* 0x0280 */
+ u16 lrcpua; /* 0x0286 */
+ u64 pstate; /* 0x0288 */
+ u64 pc; /* 0x0290 */
+ u64 sp_el0; /* 0x0298 */
+ u64 sp_el1; /* 0x02a0 */
+ u64 _02a8; /* 0x02a8 */
+ struct { /* 0x02b0 */
+ u32 _fpcr_res0;
+ u32 fpcr;
+ };
+ struct { /* 0x02b8 */
+ u32 _fpsr_res0;
+ u32 fpsr;
+ };
+ u16 sve_pregs[16]; /* 0x02c0 */
+ u16 sve_ffr; /* 0x02e0 */
+ u8 _02e2[6]; /* 0x02e2 */
+ u64 _02e8[3]; /* 0x02e8 */
+
+ u64 gpr[31]; /* 0x0300 */
+ u64 _03f8; /* 0x03f8 */
+
+ union {
+ u64 icptd[8]; /* 0x0400 */
+ /* validity-interception reason; icptr 0x01 */
+ u16 vir; /* 0x0400 */
+ /* host access interception details; icptr 0x02 */
+ struct {
+ u64 esr_el2; /* 0x0400 */
+ u8 _0408[6]; /* 0x0408 */
+ u16 pic; /* 0x040e */
+ union teid teid; /* 0x0410 */
+ gva_t far_el2; /* 0x0418 */
+ gva_t vaddr; /* 0x0420 */
+ u64 suppl; /* 0x0428 */
+ u8 gltl; /* 0x0430 */
+ u8 _0431[7]; /* 0x0431 */
+ u64 _0438; /* 0x0438 */
+ } hai;
+ /* exception-interception details; icptr 0x03 */
+ struct {
+ u64 esr_el2; /* 0x0400 */
+ u64 _0408[2]; /* 0x0408 */
+ gva_t far_el2; /* 0x0418 */
+ } trap;
+ /* timer-interception reason; icptr 0x04 */
+#define SAE_IR_TIMER_ID_VIRT BIT(6)
+#define SAE_IR_TIMER_ID_PHYS BIT(7)
+ u8 tir; /* 0x0400 */
+ };
+ u64 _0440[376]; /* 0x0440 */
+} __packed __aligned(PAGE_SIZE);
+static_assert(sizeof(struct kvm_sae_block) == PAGE_SIZE);
+
+struct kvm_sae_save_area {
+#define SAE_SAVE_AREA_FORMAT_0 0x00
+ u8 saf; /* 0x0000 */
+ u8 _0001[5]; /* 0x0001 */
+#define SAE_SAS_VALID BIT(0)
+ u16 sas; /* 0x0006 */
+ u64 sdo; /* 0x0008 */
+ u64 _0010[2]; /* 0x0010 */
+ u64 regs[508]; /* 0x0020 */
+} __packed __aligned(PAGE_SIZE);
+static_assert(sizeof(struct kvm_sae_save_area) == PAGE_SIZE);
+
+#endif /* ASM_KVM_HOST_ARM64_TYPES_H */
diff --git a/arch/s390/include/asm/kvm_host_types.h b/arch/s390/include/asm/kvm_host_types.h
index e5bdba07cab0..d308739ebcf5 100644
--- a/arch/s390/include/asm/kvm_host_types.h
+++ b/arch/s390/include/asm/kvm_host_types.h
@@ -3,6 +3,10 @@
#ifndef ASM_KVM_HOST_TYPES_H
#define ASM_KVM_HOST_TYPES_H
+#ifdef KVM_S390_ARM64
+#include <asm/kvm_host_arm64_types.h>
+#else
#include <asm/kvm_host_s390_types.h>
+#endif /* KVM_S390_ARM64 */
#endif /* ASM_KVM_HOST_TYPES_H */
diff --git a/arch/s390/include/asm/sae.h b/arch/s390/include/asm/sae.h
new file mode 100644
index 000000000000..26d89fae0836
--- /dev/null
+++ b/arch/s390/include/asm/sae.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_S390_SAE_H
+#define __ASM_S390_SAE_H
+
+#include <linux/linkage.h>
+#include <linux/types.h>
+
+#ifndef __ASSEMBLER__
+
+/* defined in arch/s390/kernel/entry.S */
+asmlinkage void sae(phys_addr_t sae_block_phys);
+
+#include <linux/io.h>
+#include <asm/kvm_host_arm64_types.h>
+
+/**
+ * stiasrm() - STore and Invalidate Arm System Register Multiple
+ * @save_area: Pointer to SAE save area
+ *
+ * Store the guest system registers to the save area.
+ * The values in the guest are no longer valid.
+ */
+static __always_inline void stiasrm(struct kvm_sae_save_area *save_area)
+{
+ asm_inline volatile(
+ " .insn rre,0xb9a70000,%[r1],0\n"
+ : "+m" (*save_area)
+ : [r1] "a" (save_area)
+ );
+}
+
+/**
+ * lasrm() - Load Arm System Register Multiple
+ *
+ * @save_area: Pointer to SAE save area
+ *
+ * Load the system registers from save_area into the guest.
+ */
+static __always_inline void lasrm(struct kvm_sae_save_area *save_area)
+{
+ asm_inline volatile(
+ " .insn rre,0xb9a60000,%[r1],0\n"
+ :
+ : "m" (*save_area), [r1] "a" (save_area)
+ );
+}
+
+#endif /* !__ASSEMBLER__ */
+#endif /* __ASM_S390_SAE_H */
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index ac3606c3babe..2d332d7c8145 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -59,6 +59,7 @@ static inline bool on_stack(struct stack_info *info,
struct stack_frame {
union {
unsigned long empty[9];
+ /* SIE stack frame */
struct {
unsigned long sie_control_block;
unsigned long sie_savearea;
@@ -68,6 +69,10 @@ struct stack_frame {
unsigned long sie_guest_asce;
unsigned long sie_irq;
};
+ /* SAE stack frame */
+ struct {
+ unsigned long sae_bear;
+ };
};
unsigned long gprs[10];
unsigned long back_chain;
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index f6dd2b67dcee..f9f9c2246074 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -70,6 +70,7 @@ int main(void)
OFFSET(__SF_SIE_CONTROL_PHYS, stack_frame, sie_control_block_phys);
OFFSET(__SF_SIE_GUEST_ASCE, stack_frame, sie_guest_asce);
OFFSET(__SF_SIE_IRQ, stack_frame, sie_irq);
+ OFFSET(__SF_SAE_BEAR, stack_frame, sae_bear);
DEFINE(STACK_FRAME_OVERHEAD, sizeof(struct stack_frame));
BLANK();
OFFSET(__SFUSER_BACKCHAIN, stack_frame_user, back_chain);
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 10dd9bbdf985..2004fd7642d7 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -245,6 +245,28 @@ EXPORT_SYMBOL(__sie64a)
EXPORT_SYMBOL(sie_exit)
#endif
+#if IS_ENABLED(CONFIG_KVM)
+/*
+ * SAE calling convention:
+ * %r2 physical address of the SAE control block
+ */
+SYM_FUNC_START(sae)
+ stmg %r6,%r14,__SF_GPRS(%r15) # store kernel registers
+ STBEAR __SF_SAE_BEAR(%r15) # save breaking event address register
+ .insn rre,0xb9a50000,%r2,0 # Start Arm Execution
+ LBEAR __SF_SAE_BEAR(%r15) # restore breaking event address register
+ lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
+ xgr %r0,%r0 # clear guest registers to
+ xgr %r1,%r1 # prevent speculative use
+ xgr %r2,%r2
+ xgr %r3,%r3
+ xgr %r4,%r4
+ xgr %r5,%r5
+ BR_EX %r14
+SYM_FUNC_END(sae)
+EXPORT_SYMBOL(sae)
+#endif
+
/*
* SVC interrupt handler routine. System calls are synchronous events and
* are entered with interrupts disabled.
diff --git a/arch/s390/tools/opcodes.txt b/arch/s390/tools/opcodes.txt
index def2659f6602..0e4773c94af0 100644
--- a/arch/s390/tools/opcodes.txt
+++ b/arch/s390/tools/opcodes.txt
@@ -594,6 +594,9 @@ b9a0 clp RRF_U0RR
b9a1 tpei RRE_RR
b9a2 ptf RRE_R0
b9a4 uvc RRF_URR
+b9a5 sae RRE_R0
+b9a6 lasrm RRE_R0
+b9a7 stiasrm RRE_R0
b9aa lptea RRF_RURR2
b9ab essa RRF_U0RR
b9ac irbm RRE_RR
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 17/24] KVM: s390: arm64: Introduce host definitions
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (15 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 16/24] s390: Introduce Start Arm Execution instruction Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 18/24] s390/hwcaps: Report SAE support as hwcap Steffen Eiden
` (7 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Add all basic definitions the arm on s390 KVM host requires. Including,
but not limited to, struct kvm*arch definitions, various functions (to
be implemented in the following patches), and various defines required
to run arm64 guests.
Enlighten asm/kvm_host.h for the new header variant. The new
header is chosen instead of asm/kvm_host_s390.h if KVM_S390_ARM64
is defined.
Co-developed-by: Andreas Grapentin <gra@linux.ibm.com>
Signed-off-by: Andreas Grapentin <gra@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/include/asm/kvm.h | 6 +
arch/s390/include/asm/kvm_host.h | 4 +
arch/s390/include/asm/kvm_host_arm64.h | 209 +++++++++++++++++++++++++
3 files changed, 219 insertions(+)
create mode 100644 arch/s390/include/asm/kvm.h
create mode 100644 arch/s390/include/asm/kvm_host_arm64.h
diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
new file mode 100644
index 000000000000..aeb11dc631d5
--- /dev/null
+++ b/arch/s390/include/asm/kvm.h
@@ -0,0 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifdef KVM_S390_ARM64
+#include <uapi/arm64/kvm.h>
+#else
+#include <uapi/asm/kvm.h>
+#endif
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 147325978225..ac3440a617c1 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -3,7 +3,11 @@
#ifndef ASM_KVM_HOST_H
#define ASM_KVM_HOST_H
+#ifdef KVM_S390_ARM64
+#include <asm/kvm_host_arm64.h>
+#else
#include <asm/kvm_host_s390.h>
+#endif
#define PGM_OPERATION 0x01
#define PGM_PRIVILEGED_OP 0x02
diff --git a/arch/s390/include/asm/kvm_host_arm64.h b/arch/s390/include/asm/kvm_host_arm64.h
new file mode 100644
index 000000000000..ab77865a74dc
--- /dev/null
+++ b/arch/s390/include/asm/kvm_host_arm64.h
@@ -0,0 +1,209 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASM_KVM_HOST_ARM64_H
+#define ASM_KVM_HOST_ARM64_H
+
+#include <linux/bug.h>
+
+#include <asm/kvm_host_types.h>
+#include <asm/debug.h>
+
+#define vcpu_gp_regs(v) ((v)->arch.sae_block.gpr)
+
+#include <arm64/kvm_host.h>
+#include <arm64/ptrace.h>
+
+#include <asm/sae.h>
+
+#define KVM_HAVE_MMU_RWLOCK
+#define KVM_MAX_VCPUS 1
+#define KVM_VCPU_RUN_PID_CHANGE
+
+#define KVM_S390_ARM64_IMPL_FEATURES 0
+#define KVM_HALT_POLL_NS_DEFAULT 50000
+
+#define KVM_S390_MANAGES_S390_GUEST 0
+
+/* Minimal (=no) vgic definitions */
+#define KVM_IRQCHIP_NUM_PINS 1
+#define irqchip_in_kernel(_k) false
+
+#define __ctxt_sys_reg(ctx, reg) NULL
+struct kvm_cpu_context {
+ /*
+ * These are just for 32 bit, which we don't have, making them RES0.
+ * They are exposed to user space.
+ */
+ u64 spsr_abt;
+ u64 spsr_und;
+ u64 spsr_irq;
+ u64 spsr_fiq;
+
+ __vector128 __aligned(16) vregs[32];
+};
+
+struct kvm_vcpu_arch {
+ struct kvm_sae_block sae_block;
+ struct kvm_sae_save_area save_area;
+ struct kvm_cpu_context ctxt;
+
+ u32 host_acrs[NUM_ACRS];
+
+ /* Hypervisor Configuration Register */
+ u64 hcr_el2;
+
+ /* Configuration flags, set once and for all before the vcpu can run */
+ u8 cflags;
+
+ /* Input flags to the hypervisor code, potentially cleared after use */
+ u8 iflags;
+
+ /* State flags for kernel bookkeeping, unused by the hypervisor code */
+ u8 sflags;
+
+ /*
+ * Don't run the guest (internal implementation need).
+ *
+ * Contrary to the flags above, this is set/cleared outside of
+ * a vcpu context, and thus cannot be mixed with the flags
+ * themselves (or the flag accesses need to be made atomic).
+ */
+ bool pause;
+
+ /* vcpu power state */
+ struct kvm_mp_state mp_state;
+ /* lock for mp_state & reset_state.reset */
+ spinlock_t mp_state_lock;
+
+ /* vcpu reset state */
+ struct vcpu_reset_state reset_state;
+
+ struct kvm_s390_mmu_cache *mc;
+
+ void *debugfs_state_data;
+};
+
+struct kvm_vcpu_stat {
+ struct kvm_vcpu_stat_generic generic;
+ /* ARM64 stats */
+ u64 hvc_exit_stat;
+ u64 wfe_exit_stat;
+ u64 wfi_exit_stat;
+ u64 mmio_exit_user;
+ u64 mmio_exit_kernel;
+ u64 signal_exits;
+ u64 exits;
+ /* GMAP stats */
+ u64 pfault_sync;
+};
+
+#define kvm_has_mte(_kvm) false
+#define vcpu_has_sve(_vcpu) false
+#define vcpu_has_ptrauth(_vcpu) false
+
+struct kvm_arch_memory_slot {
+};
+
+struct kvm_arch {
+ struct gmap *gmap;
+ u64 guest_phys_size;
+
+ /* VM-wide vCPU feature set */
+ unsigned long flags;
+
+ /* Protects VM-scoped configuration data */
+ struct mutex config_lock;
+
+ debug_info_t *dbf;
+
+ DECLARE_BITMAP(vcpu_features, KVM_VCPU_MAX_FEATURES);
+
+ unsigned long mem_limit;
+};
+
+static inline bool __vcpu_has_feature(const struct kvm_arch *ka, int feature)
+{
+ return test_bit(feature, ka->vcpu_features);
+}
+
+struct kvm_vm_stat {
+ struct kvm_vm_stat_generic generic;
+};
+
+static inline bool system_has_full_ptr_auth(void)
+{
+ return true;
+}
+
+#define kvm_vm_is_protected(_kvm) false
+#define vcpu_is_protected(_vcpu) false
+
+#define vcpu_is_loaded(_vcpu) ((_vcpu)->cpu != -1)
+
+#define KVM_HVA_ERR_BAD (-1UL)
+#define KVM_HVA_ERR_RO_BAD (-2UL)
+
+static inline bool kvm_is_error_hva(unsigned long addr)
+{
+ return IS_ERR_VALUE(addr);
+}
+
+u32 get_kvm_ipa_limit(void);
+
+/* unused, but required functions */
+static inline void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) {}
+static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
+static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {}
+static inline void kvm_arch_flush_shadow_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) {}
+static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arch_sync_events(struct kvm *kvm) {}
+static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
+static inline void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
+ struct kvm_memory_slot *slot,
+ gfn_t gfn_offset,
+ unsigned long mask) {}
+
+int kvm_handle_guest_abort(struct kvm_vcpu *vcpu);
+void kvm_reset_vcpu(struct kvm_vcpu *vcpu);
+
+/* arm64 guests do not use async-pf. Defined because Kbuild requires it as s390 kvm turns it on. */
+#define ASYNC_PF_PER_VCPU 0
+struct kvm_arch_async_pf {
+ unsigned long pfault_token;
+};
+
+#define __unsupp_async_call(fn) WARN_ONCE(true, "async not supported on kvm-arm64 %s", fn)
+
+static inline bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu)
+{
+ __unsupp_async_call(__func__);
+ return false;
+};
+
+static inline void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ __unsupp_async_call(__func__);
+};
+
+static inline bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ __unsupp_async_call(__func__);
+ return false;
+};
+
+static inline void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ __unsupp_async_call(__func__);
+};
+
+static inline void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu)
+{
+ __unsupp_async_call(__func__);
+};
+
+#define kvm_supports_32bit_el0() false
+
+#endif /* ASM_KVM_HOST_ARM64_H */
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 18/24] s390/hwcaps: Report SAE support as hwcap
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (16 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 17/24] KVM: s390: arm64: Introduce host definitions Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 19/24] KVM: s390: Add basic arm64 kvm module Steffen Eiden
` (6 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
From: Hendrik Brueckner <brueckner@linux.ibm.com>
Report SAE support as hwcap (and /proc/cpuinfo)
Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/include/asm/elf.h | 2 ++
arch/s390/include/asm/sclp.h | 5 ++++-
arch/s390/kernel/processor.c | 3 +++
drivers/s390/char/sclp_early.c | 1 +
4 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index bb63fa4d20bb..ad3108ecfb07 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h
@@ -123,6 +123,7 @@ enum {
HWCAP_NR_NNPA = 20,
HWCAP_NR_PCI_MIO = 21,
HWCAP_NR_SIE = 22,
+ HWCAP_NR_SAE = 23,
HWCAP_NR_MAX
};
@@ -150,6 +151,7 @@ enum {
#define HWCAP_NNPA BIT(HWCAP_NR_NNPA)
#define HWCAP_PCI_MIO BIT(HWCAP_NR_PCI_MIO)
#define HWCAP_SIE BIT(HWCAP_NR_SIE)
+#define HWCAP_SAE BIT(HWCAP_NR_SAE)
/*
* These are used to set parameters in the core dumps.
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index 44066550b9b1..68f61b71a2d5 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -56,7 +56,9 @@ struct sclp_core_entry {
u8 siif : 1;
u8 sigpif : 1;
u8 : 3;
- u8 reserved2[3];
+ u8 aef: 1;
+ u8 : 7;
+ u8 reserved2[2];
u8 : 2;
u8 ib : 1;
u8 cei : 1;
@@ -109,6 +111,7 @@ struct sclp_info {
unsigned char has_aeni : 1;
unsigned char has_aisi : 1;
unsigned char has_astfleie2 : 1;
+ unsigned char has_aef : 1;
unsigned int ibc;
unsigned int mtid;
unsigned int mtid_cp;
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
index e33a3eccda56..6da55a158027 100644
--- a/arch/s390/kernel/processor.c
+++ b/arch/s390/kernel/processor.c
@@ -150,6 +150,7 @@ static void show_cpu_summary(struct seq_file *m, void *v)
[HWCAP_NR_NNPA] = "nnpa",
[HWCAP_NR_PCI_MIO] = "pcimio",
[HWCAP_NR_SIE] = "sie",
+ [HWCAP_NR_SAE] = "sae",
};
int i, cpu;
@@ -254,6 +255,8 @@ static int __init setup_hwcaps(void)
/* virtualization support */
if (sclp.has_sief2)
elf_hwcap |= HWCAP_SIE;
+ if (sclp.has_aef)
+ elf_hwcap |= HWCAP_SAE;
return 0;
}
diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index 22dd797e6229..e58d24b95bd1 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -96,6 +96,7 @@ static void __init sclp_early_facilities_detect(void)
sclp.has_ib = cpue->ib;
sclp.has_cei = cpue->cei;
sclp.has_skey = cpue->skey;
+ sclp.has_aef = cpue->aef;
break;
}
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 19/24] KVM: s390: Add basic arm64 kvm module
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (17 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 18/24] s390/hwcaps: Report SAE support as hwcap Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 20/24] KVM: s390: arm64: Implement required functions Steffen Eiden
` (5 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Add basic code for the new arm64 on s390 KVM implementation.
Add kernel module boilerplate code and trivial functions.
Add tracing scaffolding.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/arm64/arm.c | 147 ++++++++++++++++++++++++++++++++++++
arch/s390/kvm/arm64/arm.h | 44 +++++++++++
arch/s390/kvm/arm64/guest.c | 90 ++++++++++++++++++++++
arch/s390/kvm/arm64/trace.h | 18 +++++
4 files changed, 299 insertions(+)
create mode 100644 arch/s390/kvm/arm64/arm.c
create mode 100644 arch/s390/kvm/arm64/arm.h
create mode 100644 arch/s390/kvm/arm64/guest.c
create mode 100644 arch/s390/kvm/arm64/trace.h
diff --git a/arch/s390/kvm/arm64/arm.c b/arch/s390/kvm/arm64/arm.c
new file mode 100644
index 000000000000..acd46059b75e
--- /dev/null
+++ b/arch/s390/kvm/arm64/arm.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/miscdevice.h>
+#include <linux/kvm.h>
+#include <linux/kvm_types.h>
+#include <linux/kvm_host.h>
+
+#include "arm.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+static unsigned long system_supported_vcpu_features(void);
+
+#define __INCL_GEN_ARM_FILE
+#include "generated/arm.inc"
+#undef __INCL_GEN_ARM_FILE
+
+int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
+{
+ int ret;
+
+ switch (ext) {
+ case KVM_CAP_NR_VCPUS:
+ case KVM_CAP_MAX_VCPUS:
+ case KVM_CAP_MAX_VCPU_ID:
+ ret = KVM_MAX_VCPUS;
+ break;
+ case KVM_CAP_ARM_VM_IPA_SIZE:
+ ret = get_kvm_ipa_limit();
+ break;
+ case KVM_CAP_IOEVENTFD:
+ case KVM_CAP_PRE_FAULT_MEMORY:
+ ret = 1;
+ break;
+ default:
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static u64 kvm_max_guest_address(void)
+{
+ u64 max_addr;
+
+ max_addr = min_t(u64, TASK_SIZE_MAX, sclp.hamax);
+ max_addr = max_t(u64, max_addr, SZ_1G - 1);
+ return ALIGN_DOWN(max_addr + 1, SZ_1G) - 1;
+}
+
+vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
+{
+ return VM_FAULT_SIGBUS;
+}
+
+long kvm_arch_dev_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ return -EINVAL;
+}
+
+u32 get_kvm_ipa_limit(void)
+{
+ return fls64(kvm_max_guest_address() + 1) - 1;
+}
+
+int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
+{
+ return 0;
+}
+
+void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
+{
+}
+
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+ struct kvm_mp_state *mp_state)
+{
+ *mp_state = READ_ONCE(vcpu->arch.mp_state);
+ return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+ struct kvm_mp_state *mp_state)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+static unsigned long system_supported_vcpu_features(void)
+{
+ unsigned long features = KVM_S390_ARM64_IMPL_FEATURES;
+
+ return features;
+}
+
+bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
+{
+ return false;
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+ int irq_source_id, int level, bool line_status)
+{
+ return -EINVAL;
+}
+
+int kvm_set_routing_entry(struct kvm *kvm,
+ struct kvm_kernel_irq_routing_entry *e,
+ const struct kvm_irq_routing_entry *ue)
+{
+ return -EINVAL;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+long kvm_arch_vcpu_unlocked_ioctl(struct file *filp, unsigned int ioctl,
+ unsigned long arg)
+{
+ return -ENOIOCTLCMD;
+}
+
+static int __init kvm_s390_arm64_init(void)
+{
+ if (!sclp.has_aef)
+ return -ENODEV;
+
+ return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+}
+
+static __exit void kvm_s390_arm64_exit(void)
+{
+ kvm_exit();
+}
+
+module_init(kvm_s390_arm64_init);
+module_exit(kvm_s390_arm64_exit);
diff --git a/arch/s390/kvm/arm64/arm.h b/arch/s390/kvm/arm64/arm.h
new file mode 100644
index 000000000000..9d903916c896
--- /dev/null
+++ b/arch/s390/kvm/arm64/arm.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ARCH_S390_KVM_ARM64_H
+#define ARCH_S390_KVM_ARM64_H
+
+static __always_inline int kvm_is_ucontrol(struct kvm *kvm)
+{
+ return 0;
+}
+
+static __always_inline int __kvm_s390_pv_destroy_page(struct page *page)
+{
+ return 0;
+}
+
+static __always_inline void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, gpa_t start, gpa_t end)
+{
+}
+
+static __always_inline int kvm_s390_pv_get_handle(struct kvm *kvm)
+{
+ return 0;
+}
+
+static __always_inline int kvm_s390_is_migration_mode(struct kvm *kvm)
+{
+ return false;
+}
+
+static __always_inline bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu)
+{
+ return false;
+}
+
+static __always_inline void kvm_s390_update_cmma_dirty(struct kvm *kvm, const struct kvm_memory_slot *old)
+{
+}
+
+/* should never be called */
+static __always_inline int kvm_s390_vm_stop_migration(struct kvm *kvm)
+{
+ return -EINVAL;
+}
+
+#endif /* ARCH_S390_KVM_ARM64_H */
diff --git a/arch/s390/kvm/arm64/guest.c b/arch/s390/kvm/arm64/guest.c
new file mode 100644
index 000000000000..1bf546bded81
--- /dev/null
+++ b/arch/s390/kvm/arm64/guest.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+
+#include <arm64/kvm_emulate.h>
+#include <arm64/kvm_nested.h>
+
+#define __INCL_GEN_ARM_FILE
+#include "generated/guest.inc"
+#undef __INCL_GEN_ARM_FILE
+
+const struct kvm_stats_desc kvm_vm_stats_desc[] = {
+ KVM_GENERIC_VM_STATS()
+};
+
+const struct kvm_stats_header kvm_vm_stats_header = {
+ .name_size = KVM_STATS_NAME_SIZE,
+ .num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
+ .id_offset = sizeof(struct kvm_stats_header),
+ .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+ .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+ sizeof(kvm_vm_stats_desc),
+};
+
+const struct kvm_stats_desc kvm_vcpu_stats_desc[] = {
+ KVM_GENERIC_VCPU_STATS(),
+ /* ARM64 stats */
+ STATS_DESC_COUNTER(VCPU, hvc_exit_stat),
+ STATS_DESC_COUNTER(VCPU, wfe_exit_stat),
+ STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
+ STATS_DESC_COUNTER(VCPU, mmio_exit_user),
+ STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
+ STATS_DESC_COUNTER(VCPU, signal_exits),
+ STATS_DESC_COUNTER(VCPU, exits),
+ /* GMAP stats */
+ STATS_DESC_COUNTER(VCPU, pfault_sync),
+};
+
+const struct kvm_stats_header kvm_vcpu_stats_header = {
+ .name_size = KVM_STATS_NAME_SIZE,
+ .num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
+ .id_offset = sizeof(struct kvm_stats_header),
+ .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+ .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+ sizeof(kvm_vcpu_stats_desc),
+};
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+ struct kvm_translation *tr)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
+ struct kvm_guest_debug *dbg)
+{
+ return -EINVAL;
+}
diff --git a/arch/s390/kvm/arm64/trace.h b/arch/s390/kvm/arm64/trace.h
new file mode 100644
index 000000000000..3a5dcd039c13
--- /dev/null
+++ b/arch/s390/kvm/arm64/trace.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#if !defined(KVM_ARM64_TRACE_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define KVM_ARM64_TRACE_KVM_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM kvm
+
+#endif /* KVM_ARM64_TRACE_KVM_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 20/24] KVM: s390: arm64: Implement required functions
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (18 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 19/24] KVM: s390: Add basic arm64 kvm module Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 21/24] KVM: s390: arm64: Implement vm/vcpu create destroy Steffen Eiden
` (4 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Implement the mostly trivial functions that the shared arm64 (kvm)
code & headers oblige s390 to implement.
MAINTAINERS: Add arch/s390/include/arm64/* to KVM/s390
Implement a very basic smccc handler that (non-compliantly) is just able
to stop a vcpu.
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
MAINTAINERS | 1 +
arch/s390/include/arm64/kvm_emulate.h | 130 ++++++++++++++++++++++++++
arch/s390/include/arm64/kvm_nested.h | 11 +++
arch/s390/include/arm64/ptrace.h | 11 +++
arch/s390/include/arm64/sysreg.h | 13 +++
arch/s390/kvm/arm64/handle_exit.c | 127 +++++++++++++++++++++++++
arch/s390/kvm/arm64/inject_fault.c | 21 +++++
7 files changed, 314 insertions(+)
create mode 100644 arch/s390/include/arm64/kvm_emulate.h
create mode 100644 arch/s390/include/arm64/kvm_nested.h
create mode 100644 arch/s390/include/arm64/ptrace.h
create mode 100644 arch/s390/include/arm64/sysreg.h
create mode 100644 arch/s390/kvm/arm64/handle_exit.c
create mode 100644 arch/s390/kvm/arm64/inject_fault.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 72294ddfa5b7..22327e180c6b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14374,6 +14374,7 @@ L: kvm@vger.kernel.org
S: Supported
T: git git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git
F: Documentation/virt/kvm/s390*
+F: arch/s390/include/arm64/*
F: arch/s390/include/asm/gmap_helpers.h
F: arch/s390/include/asm/kvm*
F: arch/s390/include/uapi/asm/kvm*
diff --git a/arch/s390/include/arm64/kvm_emulate.h b/arch/s390/include/arm64/kvm_emulate.h
new file mode 100644
index 000000000000..416c4f96db05
--- /dev/null
+++ b/arch/s390/include/arm64/kvm_emulate.h
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __S390_ARM64_KVM_EMULATE_H__
+#define __S390_ARM64_KVM_EMULATE_H__
+
+#include <asm/fault.h>
+#include <linux/kvm_host.h>
+
+#include <arm64/kvm_nested.h>
+#include <arm64/ptrace.h>
+#include <arm64/kvm_arm.h>
+#include <arm64/sysreg.h>
+
+static __always_inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
+{
+ return (unsigned long *)&vcpu->arch.sae_block.pc;
+}
+
+static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
+{
+ return (unsigned long *)&vcpu->arch.sae_block.pstate;
+}
+
+static __always_inline unsigned long *vcpu_sp_el0(const struct kvm_vcpu *vcpu)
+{
+ return (unsigned long *)&vcpu->arch.sae_block.sp_el0;
+}
+
+static __always_inline u64 *vcpu_sp_el1(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.sae_block.sp_el1;
+}
+
+static __always_inline __vector128 *vcpu_vreg(struct kvm_vcpu *vcpu, int off)
+{
+ return &vcpu->arch.ctxt.vregs[off];
+}
+
+static __always_inline u32 *vcpu_fpsr(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.sae_block.fpsr;
+}
+
+static __always_inline u32 *vcpu_fpcr(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.sae_block.fpcr;
+}
+
+static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
+{
+ return false;
+}
+
+static __always_inline u64 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.sae_block.hai.esr_el2;
+}
+
+static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
+{
+ return (unsigned long *)&vcpu->arch.hcr_el2;
+}
+
+static __always_inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.sae_block.hai.far_el2;
+}
+
+static __always_inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
+{
+ return gfn_to_gpa(vcpu->arch.sae_block.hai.teid.addr);
+}
+
+static inline u16 kvm_vcpu_fault_pic(const struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.sae_block.hai.pic & PGM_INT_CODE_MASK;
+}
+
+static __always_inline
+bool kvm_vcpu_trap_is_permission_fault(const struct kvm_vcpu *vcpu)
+{
+ return kvm_vcpu_fault_pic(vcpu) == PGM_PROTECTION;
+}
+
+static __always_inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
+{
+ return true;
+}
+
+static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
+{
+ return false;
+}
+
+static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
+{
+ return false;
+}
+
+static inline int kvm_vcpu_abt_gltl(struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.sae_block.hai.gltl;
+}
+
+static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
+{
+ u32 mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
+
+ return mode != PSR_MODE_EL0t;
+}
+
+static inline void kvm_skip_instr(struct kvm_vcpu *vcpu)
+{
+ *vcpu_pc(vcpu) += 4;
+ *vcpu_cpsr(vcpu) &= ~PSR_BTYPE_MASK;
+
+ /* advance the singlestep state machine */
+ *vcpu_cpsr(vcpu) &= ~SPSR_ELx_SS;
+}
+
+static inline void kvm_reset_fpsimd(struct kvm_vcpu *vcpu)
+{
+ memset(vcpu->arch.ctxt.vregs, 0, sizeof(vcpu->arch.ctxt.vregs));
+ vcpu->arch.sae_block.fpsr = 0;
+ vcpu->arch.sae_block.fpcr = 0;
+}
+
+#include <arm64/kvm_emulate-gen.h>
+
+#endif /* __S390_ARM64_KVM_EMULATE_H__ */
diff --git a/arch/s390/include/arm64/kvm_nested.h b/arch/s390/include/arm64/kvm_nested.h
new file mode 100644
index 000000000000..e950b1a10c41
--- /dev/null
+++ b/arch/s390/include/arm64/kvm_nested.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef ASM_KVM_NESTED_H
+#define ASM_KVM_NESTED_H
+
+static inline bool vcpu_has_nv(const struct kvm_vcpu *vcpu)
+{
+ return false;
+}
+
+#endif /* ASM_KVM_NESTED_H */
diff --git a/arch/s390/include/arm64/ptrace.h b/arch/s390/include/arm64/ptrace.h
new file mode 100644
index 000000000000..449b85582c97
--- /dev/null
+++ b/arch/s390/include/arm64/ptrace.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __S390_ARM64_PTRACE_H__
+#define __S390_ARM64_PTRACE_H__
+
+#include <arm64/sysreg.h>
+#include <uapi/arm64/ptrace.h>
+
+#include <arm64/ptrace-gen.h>
+
+#endif /* __S390_ARM64_PTRACE_H__ */
diff --git a/arch/s390/include/arm64/sysreg.h b/arch/s390/include/arm64/sysreg.h
new file mode 100644
index 000000000000..ac6b638fef56
--- /dev/null
+++ b/arch/s390/include/arm64/sysreg.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __S390_ARM64_SYSREG_H__
+#define __S390_ARM64_SYSREG_H__
+
+#include <linux/bits.h>
+#include <linux/stringify.h>
+#include <linux/kasan-tags.h>
+#include <linux/kconfig.h>
+
+#include <arm64/sysreg-gen.h>
+
+#endif /* __S390_ARM64_SYSREG_H__ */
diff --git a/arch/s390/kvm/arm64/handle_exit.c b/arch/s390/kvm/arm64/handle_exit.c
new file mode 100644
index 000000000000..07d8d7a53702
--- /dev/null
+++ b/arch/s390/kvm/arm64/handle_exit.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kvm_host.h>
+
+#include <arm64/esr.h>
+#include <arm64/kvm_emulate.h>
+
+typedef int (*exit_handle_fn)(struct kvm_vcpu *);
+
+#define PSCI_0_2_FN_SYSTEM_OFF 0x84000008
+#define PSCI_RET_NOT_SUPPORTED -1
+#define PSCI_RET_INTERNAL_FAILURE -6
+/*
+ * Temporary smc/hvc handler. Non-compliant implementation (features missing).
+ * Implements only system off so that test programs are able to end their execution.
+ * Multi-vCPU power state management and KVM_REQ_SLEEP handling are deferred
+ * to future SMP series.
+ */
+static int kvm_smccc_call_handler(struct kvm_vcpu *vcpu)
+{
+ u32 func_id = vcpu_get_reg(vcpu, 0);
+ u64 val = PSCI_RET_NOT_SUPPORTED;
+ int ret = 1;
+
+ if (func_id == PSCI_0_2_FN_SYSTEM_OFF) {
+ scoped_guard(spinlock, &vcpu->arch.mp_state_lock) {
+ WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
+ }
+ memset(&vcpu->run->system_event, 0,
+ sizeof(vcpu->run->system_event));
+ vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SHUTDOWN;
+ vcpu->run->system_event.ndata = 1;
+ vcpu->run->system_event.data[0] = 0;
+ vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
+ val = PSCI_RET_INTERNAL_FAILURE;
+ ret = 0;
+ }
+ vcpu_set_reg(vcpu, 0, val);
+
+ return ret;
+}
+
+static int handle_hvc(struct kvm_vcpu *vcpu)
+{
+ vcpu->stat.hvc_exit_stat++;
+ return kvm_smccc_call_handler(vcpu);
+}
+
+static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu)
+{
+ u64 esr = kvm_vcpu_get_esr(vcpu);
+
+ kvm_pr_unimpl("Unknown exception class: esr: %#016llx -- %s\n",
+ esr, esr_get_class_string(esr));
+
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+static exit_handle_fn arm_exit_handlers[] = {
+ [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec,
+ [ESR_ELx_EC_HVC64] = handle_hvc,
+};
+
+static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
+{
+ u64 esr = kvm_vcpu_get_esr(vcpu);
+ u8 esr_ec = ESR_ELx_EC(esr);
+
+ return arm_exit_handlers[esr_ec];
+}
+
+/*
+ * We may be single-stepping an emulated instruction. If the emulation
+ * has been completed in the kernel, we can return to userspace with a
+ * KVM_EXIT_DEBUG, otherwise userspace needs to complete its
+ * emulation first.
+ */
+static int handle_trap_exceptions(struct kvm_vcpu *vcpu)
+{
+ exit_handle_fn exit_handler;
+
+ exit_handler = kvm_get_exit_handler(vcpu);
+ return exit_handler(vcpu);
+}
+
+/* manually copied from arch/arm64/kernel/traps.c */
+static const char * const esr_class_str[] = {
+ [0 ... ESR_ELx_EC_MAX] = "UNRECOGNIZED EC",
+ [ESR_ELx_EC_UNKNOWN] = "Unknown/Uncategorized",
+ [ESR_ELx_EC_WFx] = "WFI/WFE",
+ [ESR_ELx_EC_FP_ASIMD] = "ASIMD",
+ [ESR_ELx_EC_PAC] = "PAC",
+ [ESR_ELx_EC_BTI] = "BTI",
+ [ESR_ELx_EC_ILL] = "PSTATE.IL",
+ [ESR_ELx_EC_SVC64] = "SVC (AArch64)",
+ [ESR_ELx_EC_HVC64] = "HVC (AArch64)",
+ [ESR_ELx_EC_SMC64] = "SMC (AArch64)",
+ [ESR_ELx_EC_SYS64] = "MSR/MRS (AArch64)",
+ [ESR_ELx_EC_SVE] = "SVE",
+ [ESR_ELx_EC_ERET] = "ERET/ERETAA/ERETAB",
+ [ESR_ELx_EC_FPAC] = "FPAC",
+ [ESR_ELx_EC_SME] = "SME",
+ [ESR_ELx_EC_IMP_DEF] = "EL3 IMP DEF",
+ [ESR_ELx_EC_IABT_LOW] = "IABT (lower EL)",
+ [ESR_ELx_EC_IABT_CUR] = "IABT (current EL)",
+ [ESR_ELx_EC_PC_ALIGN] = "PC Alignment",
+ [ESR_ELx_EC_DABT_LOW] = "DABT (lower EL)",
+ [ESR_ELx_EC_DABT_CUR] = "DABT (current EL)",
+ [ESR_ELx_EC_SP_ALIGN] = "SP Alignment",
+ [ESR_ELx_EC_MOPS] = "MOPS",
+ [ESR_ELx_EC_FP_EXC64] = "FP (AArch64)",
+ [ESR_ELx_EC_GCS] = "Guarded Control Stack",
+ [ESR_ELx_EC_SERROR] = "SError",
+ [ESR_ELx_EC_BREAKPT_LOW] = "Breakpoint (lower EL)",
+ [ESR_ELx_EC_BREAKPT_CUR] = "Breakpoint (current EL)",
+ [ESR_ELx_EC_SOFTSTP_LOW] = "Software Step (lower EL)",
+ [ESR_ELx_EC_SOFTSTP_CUR] = "Software Step (current EL)",
+ [ESR_ELx_EC_WATCHPT_LOW] = "Watchpoint (lower EL)",
+ [ESR_ELx_EC_WATCHPT_CUR] = "Watchpoint (current EL)",
+ [ESR_ELx_EC_BRK64] = "BRK (AArch64)",
+};
+
+const char *esr_get_class_string(unsigned long esr)
+{
+ return esr_class_str[ESR_ELx_EC(esr)];
+}
diff --git a/arch/s390/kvm/arm64/inject_fault.c b/arch/s390/kvm/arm64/inject_fault.c
new file mode 100644
index 000000000000..425dbeaa421c
--- /dev/null
+++ b/arch/s390/kvm/arm64/inject_fault.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <arm64/kvm_emulate.h>
+
+/**
+ * kvm_inject_undefined - inject an undefined instruction into the guest
+ * @vcpu: The vCPU in which to inject the exception
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_undefined(struct kvm_vcpu *vcpu)
+{
+ /* Stub until s390 supports arm64 sysregs TODO sysregs*/
+}
+
+int kvm_inject_sea(struct kvm_vcpu *vcpu, bool iabt, u64 addr)
+{
+ /* Stub until s390 supports arm64 sysregs TODO sysregs*/
+ return 1;
+}
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 21/24] KVM: s390: arm64: Implement vm/vcpu create destroy
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (19 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 20/24] KVM: s390: arm64: Implement required functions Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 22/24] KVM: s390: arm64: Implement vCPU IOCTLs Steffen Eiden
` (3 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Implement init and destroy IOCTLS for vcpu and vm.
Implement arch vm IOCTL. Use s390 gmap and gmap plumbing.
Implement function (stubs) required by gmap.
Co-developed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Co-developed-by: Andreas Grapentin <gra@linux.ibm.com>
Signed-off-by: Andreas Grapentin <gra@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/arm64/arm.c | 190 ++++++++++++++++++++++++++++++++
arch/s390/kvm/arm64/arm.h | 14 +++
arch/s390/kvm/gmap/faultin.c | 5 +
arch/s390/kvm/gmap/gmap.c | 4 +
arch/s390/kvm/gmap/kvm_mmu.c | 4 +
arch/s390/kvm/gmap/trace_gmap.h | 13 +++
6 files changed, 230 insertions(+)
diff --git a/arch/s390/kvm/arm64/arm.c b/arch/s390/kvm/arm64/arm.c
index acd46059b75e..66c4f5879d44 100644
--- a/arch/s390/kvm/arm64/arm.c
+++ b/arch/s390/kvm/arm64/arm.c
@@ -7,6 +7,9 @@
#include <linux/kvm_types.h>
#include <linux/kvm_host.h>
+#include <gmap.h>
+#include <kvm_mmu.h>
+
#include "arm.h"
#define CREATE_TRACE_POINTS
@@ -18,6 +21,8 @@ static unsigned long system_supported_vcpu_features(void);
#include "generated/arm.inc"
#undef __INCL_GEN_ARM_FILE
+#define KVM_PHYS_SHIFT (40)
+
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int ret;
@@ -51,6 +56,83 @@ static u64 kvm_max_guest_address(void)
return ALIGN_DOWN(max_addr + 1, SZ_1G) - 1;
}
+static int kvm_gmap_init(struct kvm *kvm)
+{
+ struct crst_table *table;
+
+ kvm->arch.gmap = gmap_new(kvm, gpa_to_gfn(kvm->arch.guest_phys_size));
+
+ if (!kvm->arch.gmap)
+ return -ENOMEM;
+
+ /* arm64 (on s390) do not have pfault */
+ clear_bit(GMAP_FLAG_PFAULT_ENABLED, &kvm->arch.gmap->flags);
+ set_bit(GMAP_FLAG_ALLOW_HPAGE_1M, &kvm->arch.gmap->flags);
+
+ table = dereference_asce(kvm->arch.gmap->asce);
+ crst_table_init((void *)table, _CRSTE_HOLE(table->crstes[0].h.tt).val);
+
+ return 0;
+}
+
+static int kvm_vm_type_ipa_size_shift(unsigned long type)
+{
+ int phys_shift;
+
+ phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type);
+ if (phys_shift) {
+ if (phys_shift > get_kvm_ipa_limit() ||
+ phys_shift < ARM64_MIN_PARANGE_BITS)
+ return -EINVAL;
+ } else {
+ phys_shift = KVM_PHYS_SHIFT;
+ if (phys_shift > get_kvm_ipa_limit()) {
+ pr_warn_once("%s using unsupported default IPA limit\n",
+ current->comm);
+ return -EINVAL;
+ }
+ }
+
+ return phys_shift;
+}
+
+int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
+{
+ char debug_name[32];
+ int ret;
+
+ if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
+ return -EINVAL;
+
+ ret = kvm_vm_type_ipa_size_shift(type);
+ if (ret < 0)
+ return ret;
+ kvm->arch.guest_phys_size = 1UL << ret;
+
+ mutex_init(&kvm->arch.config_lock);
+ bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
+
+ snprintf(debug_name, sizeof(debug_name), "kvm-arm64-%u-%u",
+ current->pid, get_random_u32());
+ kvm->arch.dbf = debug_register(debug_name, 32, 1, 7 * sizeof(long));
+ if (!kvm->arch.dbf)
+ return -ENOMEM;
+ debug_register_view(kvm->arch.dbf, &debug_sprintf_view);
+
+ ret = kvm_gmap_init(kvm);
+ if (ret)
+ goto out_err;
+ kvm->arch.mem_limit = kvm->arch.guest_phys_size;
+
+ VM_EVENT(kvm, 3, "vm created with type %lu", type);
+ return 0;
+
+out_err:
+ debug_unregister(kvm->arch.dbf);
+
+ return ret;
+}
+
vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
@@ -62,6 +144,13 @@ long kvm_arch_dev_ioctl(struct file *filp,
return -EINVAL;
}
+void kvm_arch_destroy_vm(struct kvm *kvm)
+{
+ kvm_destroy_vcpus(kvm);
+ debug_unregister(kvm->arch.dbf);
+ kvm->arch.gmap = gmap_put(kvm->arch.gmap);
+}
+
u32 get_kvm_ipa_limit(void)
{
return fls64(kvm_max_guest_address() + 1) - 1;
@@ -72,10 +161,45 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
return 0;
}
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
+{
+ struct kvm_sae_block *sae_block = &vcpu->arch.sae_block;
+ struct kvm_sae_save_area *save_area = &vcpu->arch.save_area;
+
+ spin_lock_init(&vcpu->arch.mp_state_lock);
+
+ /* Force users to call KVM_ARM_VCPU_INIT */
+ vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
+
+ vcpu->arch.mc = kvm_s390_new_mmu_cache();
+ if (!vcpu->arch.mc)
+ return -ENOMEM;
+
+ save_area->sdo = virt_to_phys(sae_block);
+
+ sae_block->hbasce = vcpu->kvm->arch.gmap->asce.val;
+ sae_block->mso = 0L;
+ sae_block->msl = vcpu->kvm->arch.mem_limit - 1;
+ sae_block->save_area = virt_to_phys(save_area);
+
+ VM_EVENT(vcpu->kvm, 3,
+ "create cpu %d at 0x%p, sae block at 0x%p, satellite at 0x%p",
+ vcpu->vcpu_id, vcpu, &vcpu->arch.sae_block,
+ &vcpu->arch.save_area);
+ return 0;
+}
+
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
}
+void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
+{
+ kvm_s390_free_mmu_cache(vcpu->arch.mc);
+
+ VCPU_EVENT(vcpu, 3, "%s", "free cpu");
+}
+
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
@@ -101,6 +225,72 @@ static unsigned long system_supported_vcpu_features(void)
return features;
}
+int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
+ struct kvm_dirty_log *log)
+{
+ return s390_kvm_mmu_get_dirty_log(kvm, log);
+}
+
+bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+ scoped_guard(read_lock, &kvm->mmu_lock)
+ return gmap_age_gfn(kvm->arch.gmap, range->start, range->end);
+}
+
+void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
+{
+ gfn_t last_gfn = memslot->base_gfn + memslot->npages;
+
+ scoped_guard(read_lock, &kvm->mmu_lock)
+ gmap_sync_dirty_log(kvm->arch.gmap, memslot->base_gfn, last_gfn);
+}
+
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+ const struct kvm_memory_slot *old,
+ struct kvm_memory_slot *new,
+ enum kvm_mr_change change)
+{
+ return s390_kvm_mmu_prepare_memory_region(kvm, old, new, change);
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot *old,
+ const struct kvm_memory_slot *new,
+ enum kvm_mr_change change)
+{
+}
+
+bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+ return gmap_unmap_gfn_range(kvm->arch.gmap, range->slot, range->start, range->end);
+}
+
+bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+ scoped_guard(read_lock, &kvm->mmu_lock)
+ return dat_test_age_gfn(kvm->arch.gmap->asce, range->start, range->end);
+}
+
+int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+
+ switch (ioctl) {
+ case KVM_ARM_PREFERRED_TARGET: {
+ struct kvm_vcpu_init init = {
+ .target = KVM_ARM_TARGET_GENERIC_V8,
+ };
+
+ if (copy_to_user(argp, &init, sizeof(init)))
+ return -EFAULT;
+
+ return 0;
+ }
+
+ default:
+ return -EINVAL;
+ }
+}
+
bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
{
return false;
diff --git a/arch/s390/kvm/arm64/arm.h b/arch/s390/kvm/arm64/arm.h
index 9d903916c896..760230685ca1 100644
--- a/arch/s390/kvm/arm64/arm.h
+++ b/arch/s390/kvm/arm64/arm.h
@@ -2,6 +2,20 @@
#ifndef ARCH_S390_KVM_ARM64_H
#define ARCH_S390_KVM_ARM64_H
+#include <linux/compiler_attributes.h>
+#include <linux/kvm_host.h>
+
+#define VM_EVENT(d_kvm, d_loglevel, d_string, d_args...) \
+ debug_sprintf_event((d_kvm)->arch.dbf, d_loglevel, \
+ __stringify(KVM_DEV_NAME) ": " d_string "\n", \
+ d_args)
+
+#define VCPU_EVENT(d_vcpu, d_loglevel, d_string, d_args...) \
+ debug_sprintf_event((d_vcpu)->kvm->arch.dbf, d_loglevel, \
+ __stringify(KVM_DEV_NAME) " %02d[%016llx-%016llx]: " d_string "\n", \
+ (d_vcpu)->vcpu_id, (d_vcpu)->arch.sae_block.pstate, \
+ (d_vcpu)->arch.sae_block.pc, d_args)
+
static __always_inline int kvm_is_ucontrol(struct kvm *kvm)
{
return 0;
diff --git a/arch/s390/kvm/gmap/faultin.c b/arch/s390/kvm/gmap/faultin.c
index 1dc79807012c..2e93bd563d5c 100644
--- a/arch/s390/kvm/gmap/faultin.c
+++ b/arch/s390/kvm/gmap/faultin.c
@@ -10,6 +10,11 @@
#include "gmap.h"
#include "faultin.h"
+#ifdef KVM_S390_ARM64
+#include "arm.h"
+#else
+#include "s390.h"
+#endif
bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu);
#define CREATE_TRACE_POINTS
diff --git a/arch/s390/kvm/gmap/gmap.c b/arch/s390/kvm/gmap/gmap.c
index 3f3fa864cc36..bf91e3d5013b 100644
--- a/arch/s390/kvm/gmap/gmap.c
+++ b/arch/s390/kvm/gmap/gmap.c
@@ -21,7 +21,11 @@
#include "dat.h"
#include "gmap.h"
+#ifdef KVM_S390_ARM64
+#include "arm.h"
+#else
#include "s390.h"
+#endif
#include "faultin.h"
static int gmap_limit_to_type(gfn_t limit)
diff --git a/arch/s390/kvm/gmap/kvm_mmu.c b/arch/s390/kvm/gmap/kvm_mmu.c
index 24e618f77be1..4e2da60b9859 100644
--- a/arch/s390/kvm/gmap/kvm_mmu.c
+++ b/arch/s390/kvm/gmap/kvm_mmu.c
@@ -3,7 +3,11 @@
#include <linux/kvm_types.h>
#include <linux/kvm_host.h>
+#ifdef KVM_S390_ARM64
+#include "arm.h"
+#else
#include "s390.h"
+#endif
#include "gmap.h"
#include "dat.h"
#include "kvm_mmu.h"
diff --git a/arch/s390/kvm/gmap/trace_gmap.h b/arch/s390/kvm/gmap/trace_gmap.h
index 78d26dae59f9..1dce3ef3b0d9 100644
--- a/arch/s390/kvm/gmap/trace_gmap.h
+++ b/arch/s390/kvm/gmap/trace_gmap.h
@@ -13,6 +13,18 @@
#undef TRACE_INCLUDE_FILE
#define TRACE_INCLUDE_FILE trace_gmap
+#ifdef KVM_S390_ARM64
+#define __KVM_FIELDS \
+ __field(unsigned long, pstate) \
+ __field(unsigned long, pc)
+#define __KVM_ASSIGN ({\
+ __entry->pstate = vcpu->arch.sae_block.pstate; \
+ __entry->pc = vcpu->arch.sae_block.pc; \
+ })
+#define __KVM_PRINT \
+ __entry->pstate, \
+ __entry->pc
+#else
#define __KVM_FIELDS \
__field(unsigned long, pswmask) \
__field(unsigned long, pswaddr)
@@ -23,6 +35,7 @@
#define __KVM_PRINT \
__entry->pswmask,\
__entry->pswaddr
+#endif
TRACE_EVENT(kvm_s390_major_guest_pfault,
TP_PROTO(struct kvm_vcpu *vcpu),
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 22/24] KVM: s390: arm64: Implement vCPU IOCTLs
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (20 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 21/24] KVM: s390: arm64: Implement vm/vcpu create destroy Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-09-30 17:34 ` [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler Steffen Eiden
` (2 subsequent siblings)
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Implement all required vCPU (arch) IOCTLs.
Co-developed-by: Andreas Grapentin <gra@linux.ibm.com>
Signed-off-by: Andreas Grapentin <gra@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/arm64/arm.c | 417 ++++++++++++++++++++++++++++++
arch/s390/kvm/arm64/guest.c | 45 ++++
arch/s390/kvm/arm64/handle_exit.c | 32 +++
arch/s390/kvm/arm64/handle_exit.h | 9 +
arch/s390/kvm/arm64/reset.c | 71 +++++
arch/s390/kvm/arm64/trace.h | 36 ++-
6 files changed, 609 insertions(+), 1 deletion(-)
create mode 100644 arch/s390/kvm/arm64/handle_exit.h
create mode 100644 arch/s390/kvm/arm64/reset.c
diff --git a/arch/s390/kvm/arm64/arm.c b/arch/s390/kvm/arm64/arm.c
index 66c4f5879d44..803325fc3d55 100644
--- a/arch/s390/kvm/arm64/arm.c
+++ b/arch/s390/kvm/arm64/arm.c
@@ -6,11 +6,19 @@
#include <linux/kvm.h>
#include <linux/kvm_types.h>
#include <linux/kvm_host.h>
+#include <linux/cleanup.h>
+#include <linux/fpu.h>
+
+#include <asm/access-regs.h>
+
+#include <arm64/kvm_emulate.h>
+#include <arm64/sysreg.h>
#include <gmap.h>
#include <kvm_mmu.h>
#include "arm.h"
+#include "handle_exit.h"
#define CREATE_TRACE_POINTS
#include "trace.h"
@@ -200,6 +208,22 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
VCPU_EVENT(vcpu, 3, "%s", "free cpu");
}
+void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+ save_access_regs(&vcpu->arch.host_acrs[0]);
+ vcpu->cpu = cpu;
+
+ lasrm(&vcpu->arch.save_area);
+}
+
+void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
+{
+ stiasrm(&vcpu->arch.save_area);
+
+ vcpu->cpu = -1;
+ restore_access_regs(&vcpu->arch.host_acrs[0]);
+}
+
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
@@ -225,6 +249,399 @@ static unsigned long system_supported_vcpu_features(void)
return features;
}
+bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
+{
+ return vcpu_mode_priv(vcpu);
+}
+
+int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+
+ if (!kvm_vcpu_initialized(vcpu))
+ return -ENOEXEC;
+
+ if (!kvm_arm_vcpu_is_finalized(vcpu))
+ return -EPERM;
+
+ if (likely(READ_ONCE(vcpu->pid)))
+ return 0;
+
+ scoped_guard(mutex, &kvm->arch.config_lock)
+ set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
+
+ return 0;
+}
+
+/**
+ * check_vcpu_requests - check and handle pending vCPU requests
+ * @vcpu: the VCPU pointer
+ *
+ * Return: 1 if we should enter the guest
+ * 0 if we should exit to userspace
+ * < 0 if we should exit to userspace, where the return value indicates
+ * an error
+ */
+static int check_vcpu_requests(struct kvm_vcpu *vcpu)
+{
+ if (kvm_request_pending(vcpu)) {
+ if (kvm_test_request(KVM_REQ_VM_DEAD, vcpu))
+ return -EIO;
+ if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
+ kvm_reset_vcpu(vcpu);
+ /*
+ * Clear IRQ_PENDING requests that were made to guarantee
+ * that a VCPU sees new virtual interrupts.
+ */
+ kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
+
+ if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
+ asce_flush_tlb(vcpu->kvm->arch.gmap->asce);
+ }
+
+ return 1;
+}
+
+static int kvm_vcpu_initialize(struct kvm_vcpu *vcpu,
+ const struct kvm_vcpu_init *init)
+{
+ unsigned long features = init->features[0];
+ struct kvm *kvm = vcpu->kvm;
+
+ guard(mutex)(&kvm->arch.config_lock);
+ if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
+ kvm_vcpu_init_changed(vcpu, init))
+ return -EINVAL;
+
+ bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
+
+ kvm_reset_vcpu(vcpu);
+
+ set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
+ vcpu_set_flag(vcpu, VCPU_INITIALIZED);
+
+ return 0;
+}
+
+static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
+ const struct kvm_vcpu_init *init)
+{
+ int ret;
+
+ if (init->target != KVM_ARM_TARGET_GENERIC_V8)
+ return -EINVAL;
+
+ ret = kvm_vcpu_init_check_features(vcpu, init);
+ if (ret)
+ return ret;
+
+ if (!kvm_vcpu_initialized(vcpu))
+ return kvm_vcpu_initialize(vcpu, init);
+
+ if (kvm_vcpu_init_changed(vcpu, init))
+ return -EINVAL;
+
+ kvm_reset_vcpu(vcpu);
+
+ return 0;
+}
+
+static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_init *init)
+{
+ struct kvm_sae_save_area *save_area = &vcpu->arch.save_area;
+ struct kvm_sae_block *sae_block = &vcpu->arch.sae_block;
+ int ret;
+
+ sae_block->save_area = virt_to_phys(save_area);
+ save_area->sdo = virt_to_phys(sae_block);
+
+ ret = kvm_vcpu_set_target(vcpu, init);
+ if (ret)
+ return ret;
+
+ scoped_guard(spinlock, &vcpu->arch.mp_state_lock) {
+ WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
+ }
+
+ return 0;
+}
+
+int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
+ bool line_status)
+{
+ /* stub for now*/
+ return -EINVAL;
+}
+
+static void adjust_pc(struct kvm_vcpu *vcpu)
+{
+ if (vcpu_get_flag(vcpu, INCREMENT_PC)) {
+ kvm_skip_instr(vcpu);
+ vcpu_clear_flag(vcpu, INCREMENT_PC);
+ }
+}
+
+static noinstr void arm_vcpu_enter_exit(phys_addr_t sae_block)
+{
+ guest_timing_enter_irqoff();
+ guest_state_enter_irqoff();
+
+ /*
+ * External interrupts may occur while the SAE instruction is executing
+ * and must preempt guest execution to maintain responsiveness of the
+ * host.
+ *
+ * As a temporary workaround, run SAE with interrupts enabled so that any
+ * interrupt is taken via the normal host interrupt path rather than
+ * being subsumed inside the SAE window.
+ */
+ raw_local_irq_enable();
+ sae(sae_block);
+ raw_local_irq_disable();
+
+ guest_state_exit_irqoff();
+ guest_timing_exit_irqoff();
+}
+
+/** kvm_arch_vcpu_ioctl_run() - run arm64 vCPU
+ *
+ * Execute arm64 guest instructions using SAE.
+ *
+ * Returns:
+ * 1 enter the guest (should not be observed by userspace)
+ * 0 exit to userspace
+ * < 0 exit to userspace, where the return value indicates an error
+ *
+ *
+ */
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
+{
+ DECLARE_KERNEL_FPU_ONSTACK32(fpu_save);
+ struct kvm_run *kvm_run = vcpu->run;
+ int ret;
+
+ if (kvm_run->exit_reason == KVM_EXIT_MMIO) {
+ ret = kvm_handle_mmio_return(vcpu);
+ if (ret <= 0)
+ return ret;
+ }
+
+ vcpu_load(vcpu);
+
+ kernel_fpu_begin(&fpu_save, KERNEL_FPC | KERNEL_VXR);
+ load_vx_regs((vcpu->arch.ctxt.vregs));
+
+ if (!vcpu->wants_to_run) {
+ ret = -EINTR;
+ goto out;
+ }
+
+ kvm_sigset_activate(vcpu);
+
+ might_fault();
+
+ ret = 1;
+ kvm_run->exit_reason = KVM_EXIT_UNKNOWN;
+ while (ret > 0) {
+ ret = kvm_xfer_to_guest_mode_handle_work(vcpu);
+ if (!ret)
+ ret = 1;
+
+ if (ret > 0)
+ ret = check_vcpu_requests(vcpu);
+
+ vcpu->arch.sae_block.icptr = 0;
+
+ local_irq_disable();
+ xfer_to_guest_mode_prepare();
+ /*
+ * The full memory barrier in smp_store_mb() orders the mode
+ * store against the kvm_request_pending() check below, so
+ * any pending kick is visible before we decide to enter the
+ * guest.
+ */
+ smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+
+ if (ret <= 0 || kvm_request_pending(vcpu) ||
+ xfer_to_guest_mode_work_pending()) {
+ vcpu->mode = OUTSIDE_GUEST_MODE;
+ local_irq_enable();
+ continue;
+ }
+
+ trace_kvm_entry(*vcpu_pc(vcpu));
+
+ adjust_pc(vcpu);
+
+ arm_vcpu_enter_exit(virt_to_phys(&vcpu->arch.sae_block));
+
+ vcpu->mode = OUTSIDE_GUEST_MODE;
+ vcpu->stat.exits++;
+
+ local_irq_enable();
+ trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
+
+ ret = handle_exit(vcpu);
+ }
+
+ kvm_sigset_deactivate(vcpu);
+out:
+ if (unlikely(vcpu_get_flag(vcpu, INCREMENT_PC)))
+ adjust_pc(vcpu);
+
+ save_vx_regs(vcpu->arch.ctxt.vregs);
+ kernel_fpu_end(&fpu_save, KERNEL_FPC | KERNEL_VXR);
+ vcpu_put(vcpu);
+
+ return ret;
+}
+
+static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret;
+
+ switch (attr->group) {
+ default:
+ ret = -ENXIO;
+ break;
+ }
+
+ return ret;
+}
+
+static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret;
+
+ switch (attr->group) {
+ default:
+ ret = -ENXIO;
+ break;
+ }
+
+ return ret;
+}
+
+static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
+ struct kvm_device_attr *attr)
+{
+ int ret;
+
+ switch (attr->group) {
+ default:
+ ret = -ENXIO;
+ break;
+ }
+
+ return ret;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
+{
+ struct kvm_vcpu *vcpu = filp->private_data;
+ void __user *argp = (void __user *)arg;
+ struct kvm_device_attr attr;
+ int ret;
+
+ switch (ioctl) {
+ case KVM_ARM_VCPU_INIT: {
+ struct kvm_vcpu_init init;
+
+ ret = -EFAULT;
+ if (copy_from_user(&init, argp, sizeof(init)))
+ break;
+
+ ret = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
+ break;
+ }
+ case KVM_SET_ONE_REG:
+ case KVM_GET_ONE_REG: {
+ struct kvm_one_reg reg;
+
+ ret = -ENOEXEC;
+ if (unlikely(!kvm_vcpu_initialized(vcpu)))
+ break;
+
+ ret = -EFAULT;
+ if (copy_from_user(®, argp, sizeof(reg)))
+ break;
+
+ if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
+ kvm_reset_vcpu(vcpu);
+
+ if (ioctl == KVM_SET_ONE_REG)
+ ret = kvm_arm_set_reg(vcpu, ®);
+ else
+ ret = kvm_arm_get_reg(vcpu, ®);
+ break;
+ }
+ case KVM_GET_REG_LIST: {
+ struct kvm_reg_list __user *user_list = argp;
+ struct kvm_reg_list reg_list;
+ unsigned int n;
+
+ ret = -ENOEXEC;
+ if (unlikely(!kvm_vcpu_initialized(vcpu)))
+ break;
+ ret = -EPERM;
+ if (!kvm_arm_vcpu_is_finalized(vcpu))
+ break;
+ ret = -EFAULT;
+ if (copy_from_user(®_list, user_list, sizeof(reg_list)))
+ break;
+ n = reg_list.n;
+ reg_list.n = kvm_arm_num_regs(vcpu);
+ if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
+ break;
+ ret = -E2BIG;
+ if (n < reg_list.n)
+ break;
+ ret = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
+ break;
+ }
+ case KVM_ARM_VCPU_FINALIZE: {
+ int what;
+
+ if (!kvm_vcpu_initialized(vcpu))
+ return -ENOEXEC;
+
+ if (get_user(what, (const int __user *)argp))
+ return -EFAULT;
+
+ ret = kvm_arm_vcpu_finalize(vcpu, what);
+ break;
+ }
+ case KVM_SET_DEVICE_ATTR: {
+ ret = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ ret = kvm_arm_vcpu_set_attr(vcpu, &attr);
+ break;
+ }
+ case KVM_GET_DEVICE_ATTR: {
+ ret = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ ret = kvm_arm_vcpu_get_attr(vcpu, &attr);
+ break;
+ }
+ case KVM_HAS_DEVICE_ATTR: {
+ ret = -EFAULT;
+ if (copy_from_user(&attr, argp, sizeof(attr)))
+ break;
+ ret = kvm_arm_vcpu_has_attr(vcpu, &attr);
+ break;
+ }
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
struct kvm_dirty_log *log)
{
diff --git a/arch/s390/kvm/arm64/guest.c b/arch/s390/kvm/arm64/guest.c
index 1bf546bded81..4ea6fe2c270d 100644
--- a/arch/s390/kvm/arm64/guest.c
+++ b/arch/s390/kvm/arm64/guest.c
@@ -45,6 +45,51 @@ const struct kvm_stats_header kvm_vcpu_stats_header = {
sizeof(kvm_vcpu_stats_desc),
};
+int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+ int ret;
+
+ ret = copy_core_reg_indices(vcpu, uindices);
+ if (ret < 0)
+ return ret;
+ uindices += ret;
+
+ return 0;
+}
+
+unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
+{
+ return num_core_regs(vcpu);
+}
+
+int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ /* We currently use nothing arch-specific in upper 32 bits */
+ if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
+ return -EINVAL;
+
+ switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
+ case KVM_REG_ARM_CORE:
+ return get_core_reg(vcpu, reg);
+ default:
+ return -EINVAL;
+ }
+}
+
+int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ /* We currently use nothing arch-specific in upper 32 bits */
+ if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
+ return -EINVAL;
+
+ switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
+ case KVM_REG_ARM_CORE:
+ return set_core_reg(vcpu, reg);
+ default:
+ return -EINVAL;
+ }
+}
+
int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
diff --git a/arch/s390/kvm/arm64/handle_exit.c b/arch/s390/kvm/arm64/handle_exit.c
index 07d8d7a53702..dbf6edaeefaf 100644
--- a/arch/s390/kvm/arm64/handle_exit.c
+++ b/arch/s390/kvm/arm64/handle_exit.c
@@ -5,6 +5,8 @@
#include <arm64/esr.h>
#include <arm64/kvm_emulate.h>
+#include "handle_exit.h"
+
typedef int (*exit_handle_fn)(struct kvm_vcpu *);
#define PSCI_0_2_FN_SYSTEM_OFF 0x84000008
@@ -84,6 +86,36 @@ static int handle_trap_exceptions(struct kvm_vcpu *vcpu)
return exit_handler(vcpu);
}
+/*
+ * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
+ * proper exit to userspace.
+ */
+int handle_exit(struct kvm_vcpu *vcpu)
+{
+ u8 icptr = vcpu->arch.sae_block.icptr;
+ int ret = 1;
+
+ switch (icptr) {
+ case SAE_ICPTR_SPURIOUS:
+ break;
+ case SAE_ICPTR_VALIDITY:
+ WARN_ONCE(true, "SAE: validity intercept. vir: 0x%04x",
+ vcpu->arch.sae_block.vir);
+ vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ ret = 0;
+ break;
+ case SAE_ICPTR_GUEST_ADDRESS_SIZE:
+ case SAE_ICPTR_HOST_ACCESS_EXCEPTION:
+ case SAE_ICPTR_SYNCHRONOUS_EXCEPTION:
+ ret = handle_trap_exceptions(vcpu);
+ break;
+ default:
+ vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ ret = 0;
+ }
+ return ret;
+}
+
/* manually copied from arch/arm64/kernel/traps.c */
static const char * const esr_class_str[] = {
[0 ... ESR_ELx_EC_MAX] = "UNRECOGNIZED EC",
diff --git a/arch/s390/kvm/arm64/handle_exit.h b/arch/s390/kvm/arm64/handle_exit.h
new file mode 100644
index 000000000000..65ae58721537
--- /dev/null
+++ b/arch/s390/kvm/arm64/handle_exit.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef KVM_ARM64_HANDLE_EXIT_H
+#define KVM_ARM64_HANDLE_EXIT_H
+
+#include <linux/kvm_host.h>
+
+int handle_exit(struct kvm_vcpu *vcpu);
+
+#endif /* KVM_ARM64_HANDLE_EXIT_H */
diff --git a/arch/s390/kvm/arm64/reset.c b/arch/s390/kvm/arm64/reset.c
new file mode 100644
index 000000000000..e4cdce1dbf9d
--- /dev/null
+++ b/arch/s390/kvm/arm64/reset.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kvm_host.h>
+#include <linux/fpu.h>
+
+#include <arm64/kvm_emulate.h>
+#include <arm64/kvm_nested.h>
+
+bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu)
+{
+ return true;
+}
+
+static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
+{
+ vcpu->arch.hcr_el2 = HCR_EL2_E2H | HCR_EL2_RW | HCR_EL2_AMO |
+ HCR_EL2_IMO | HCR_EL2_FMO | HCR_EL2_PTW;
+ /* traps */
+ vcpu->arch.hcr_el2 |= HCR_EL2_TSC | HCR_EL2_TID1 | HCR_EL2_TID2 |
+ HCR_EL2_TID3 | HCR_EL2_TID4 | HCR_EL2_TID5 |
+ HCR_EL2_TIDCP | HCR_EL2_TLOR;
+}
+
+void kvm_reset_vcpu(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_reset_state reset_state;
+ bool loaded;
+
+ scoped_guard(spinlock, &vcpu->arch.mp_state_lock) {
+ reset_state = vcpu->arch.reset_state;
+ vcpu->arch.reset_state.reset = false;
+ }
+
+ /*
+ * Disable preemption around the vcpu reset as we might otherwise race with
+ * preempt notifiers which call stiasrm/lasrm from put/load
+ */
+ preempt_disable();
+
+ /* The reset must run with an unloaded save area */
+ loaded = vcpu_is_loaded(vcpu);
+ if (loaded)
+ vcpu_put(vcpu);
+
+ kvm_reset_vcpu_core(vcpu);
+
+ /* Reset special registers */
+ vcpu_reset_hcr(vcpu);
+
+ if (reset_state.reset) {
+ *vcpu_pc(vcpu) = reset_state.pc;
+ vcpu_clear_flag(vcpu, PENDING_EXCEPTION);
+ vcpu_clear_flag(vcpu, EXCEPT_MASK);
+ vcpu_clear_flag(vcpu, INCREMENT_PC);
+ vcpu_set_reg(vcpu, 0, reset_state.r0);
+ }
+
+ /* Load new vx-regs into HW if they are currently loaded */
+ if (current->thread.kfpu_flags)
+ load_vx_regs(vcpu->arch.ctxt.vregs);
+
+ if (loaded)
+ vcpu_load(vcpu);
+
+ preempt_enable();
+}
+
+int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature)
+{
+ return -EINVAL;
+}
diff --git a/arch/s390/kvm/arm64/trace.h b/arch/s390/kvm/arm64/trace.h
index 3a5dcd039c13..0380e45fba28 100644
--- a/arch/s390/kvm/arm64/trace.h
+++ b/arch/s390/kvm/arm64/trace.h
@@ -5,7 +5,41 @@
#include <linux/tracepoint.h>
#undef TRACE_SYSTEM
-#define TRACE_SYSTEM kvm
+#define TRACE_SYSTEM kvm_arm64
+#undef TRACE_SYSTEM_VAR
+#define TRACE_SYSTEM_VAR kvm_arm64
+
+TRACE_EVENT(kvm_entry,
+ TP_PROTO(unsigned long vcpu_pc),
+ TP_ARGS(vcpu_pc),
+
+ TP_STRUCT__entry(
+ __field(unsigned long, vcpu_pc)
+ ),
+
+ TP_fast_assign(__entry->vcpu_pc = vcpu_pc;),
+
+ TP_printk("PC: 0x%016lx", __entry->vcpu_pc)
+);
+
+TRACE_EVENT(kvm_exit,
+ TP_PROTO(unsigned int esr_ec, unsigned long vcpu_pc),
+ TP_ARGS(esr_ec, vcpu_pc),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, esr_ec )
+ __field(unsigned long, vcpu_pc )
+ ),
+
+ TP_fast_assign(
+ __entry->esr_ec = esr_ec;
+ __entry->vcpu_pc = vcpu_pc;
+ ),
+
+ TP_printk("HSR_EC: 0x%04x, PC: 0x%016lx",
+ __entry->esr_ec,
+ __entry->vcpu_pc)
+);
#endif /* KVM_ARM64_TRACE_KVM_H */
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (21 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 22/24] KVM: s390: arm64: Implement vCPU IOCTLs Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-10-01 12:10 ` Arnd Bergmann
2026-09-30 17:34 ` [PATCH v9 24/24] KVM: s390: arm64: Integrate arm on s390 Steffen Eiden
2026-10-01 11:04 ` (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Marc Zyngier
24 siblings, 1 reply; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Add host functionality to page in guest memory. If the guest does
something unexpected or illegal exit to userspace abort guest execution.
This behaviour will be changed to guest error injects once all sysregs
are accessible for the host. Add pre-fault handler.
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/arm64/handle_exit.c | 2 +
arch/s390/kvm/arm64/mmio.c | 15 +++
arch/s390/kvm/arm64/mmu.c | 200 ++++++++++++++++++++++++++++++
arch/s390/kvm/arm64/trace.h | 49 ++++++++
4 files changed, 266 insertions(+)
create mode 100644 arch/s390/kvm/arm64/mmio.c
create mode 100644 arch/s390/kvm/arm64/mmu.c
diff --git a/arch/s390/kvm/arm64/handle_exit.c b/arch/s390/kvm/arm64/handle_exit.c
index dbf6edaeefaf..e0c7773c2165 100644
--- a/arch/s390/kvm/arm64/handle_exit.c
+++ b/arch/s390/kvm/arm64/handle_exit.c
@@ -62,6 +62,8 @@ static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu)
static exit_handle_fn arm_exit_handlers[] = {
[0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec,
[ESR_ELx_EC_HVC64] = handle_hvc,
+ [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort,
+ [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort,
};
static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
diff --git a/arch/s390/kvm/arm64/mmio.c b/arch/s390/kvm/arm64/mmio.c
new file mode 100644
index 000000000000..908a6b43ddf7
--- /dev/null
+++ b/arch/s390/kvm/arm64/mmio.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kvm_host.h>
+#include <linux/bitfield.h>
+
+#include <trace/events/kvm.h>
+
+#include <arm64/kvm_emulate.h>
+#include <arm64/sysreg.h>
+
+#include "trace.h"
+
+#define __INCL_GEN_ARM_FILE
+#include "generated/mmio.inc"
+#undef __INCL_GEN_ARM_FILE
diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
new file mode 100644
index 000000000000..3c1c8a2def73
--- /dev/null
+++ b/arch/s390/kvm/arm64/mmu.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kvm_host.h>
+
+#include <arm64/kvm_emulate.h>
+
+#include <faultin.h>
+
+#include "trace.h"
+
+static inline bool kvm_s390_cur_gmap_fault_is_write(struct kvm_vcpu *vcpu)
+{
+ return (vcpu->arch.sae_block.hai.pic & PGM_INT_CODE_MASK) == PGM_PROTECTION ||
+ vcpu->arch.sae_block.hai.teid.fsi == TEID_FSI_STORE;
+}
+
+/*
+ * user_mem_abort() - handle a dat fault for the gmap of a vcpu
+ *
+ * Return: 0 on success, < 0 in case of error.
+ * Context: The mm lock must not be held before calling. May sleep.
+ */
+static int user_mem_abort(struct kvm_vcpu *vcpu, gpa_t fault_ipa,
+ struct kvm_memory_slot *slot, hva_t hva)
+{
+ struct guest_fault f = { };
+ int ret;
+
+ if (kvm_s390_cur_gmap_fault_is_write(vcpu))
+ f.write_attempt = FOLL_WRITE;
+ f.gfn = gpa_to_gfn(fault_ipa);
+
+ ret = kvm_s390_faultin_gfn(vcpu, NULL, &f);
+ if (ret <= 0)
+ return ret;
+ if (ret == PGM_ADDRESSING)
+ /*
+ * Without the relevant sysregs we cannot do anything for now.
+ * Go back to userspace with an error. TODO sysreg handling
+ */
+ return -ENOEXEC;
+ KVM_BUG_ON(ret, vcpu->kvm);
+ return -EINVAL;
+}
+
+static int kvm_handle_pic(struct kvm_vcpu *vcpu, bool *translation)
+{
+ switch (kvm_vcpu_fault_pic(vcpu)) {
+ /* expected cases: */
+ case PGM_ASCE_TYPE:
+ case PGM_REGION_FIRST_TRANS:
+ case PGM_REGION_SECOND_TRANS:
+ case PGM_REGION_THIRD_TRANS:
+ case PGM_SEGMENT_TRANSLATION:
+ case PGM_PAGE_TRANSLATION:
+ *translation = true;
+ break;
+ case PGM_PROTECTION:
+ break;
+ /* unexpected cases: */
+ case 0:
+ KVM_BUG(1, vcpu->kvm, "On MMU fault path but no fault occurred");
+ return -EFAULT;
+ default:
+ KVM_BUG(1, vcpu->kvm, "Unexpected program interrupt 0x%x, TEID 0x%016lx",
+ vcpu->arch.sae_block.hai.pic, vcpu->arch.sae_block.hai.teid.val);
+ send_sig(SIGSEGV, current, 0);
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
+{
+ struct kvm_memory_slot *memslot;
+ bool translation = false;
+ phys_addr_t fault_ipa;
+ unsigned long hva;
+ bool write_fault;
+ bool guest_size_err;
+ bool writable;
+ bool is_iabt;
+ int ret;
+ gfn_t gfn;
+
+ fault_ipa = kvm_vcpu_get_fault_ipa(vcpu);
+ is_iabt = kvm_vcpu_trap_is_iabt(vcpu);
+ guest_size_err = vcpu->arch.sae_block.icptr == SAE_ICPTR_GUEST_ADDRESS_SIZE;
+
+ if (guest_size_err) {
+ translation = true;
+ } else {
+ ret = kvm_handle_pic(vcpu, &translation);
+ if (ret)
+ return ret;
+ }
+
+ if (translation) {
+ /*
+ * For both cases:
+ * Without the relevant sysregs we cannot do anything for now.
+ * Go back to userspace with an error. TODO sysreg handling
+ */
+ if (fault_ipa >= BIT_ULL(get_kvm_ipa_limit()))
+ return -ENOEXEC;
+
+ if (fault_ipa >= vcpu->kvm->arch.guest_phys_size)
+ return -ENOEXEC;
+ }
+
+ trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_esr(vcpu),
+ kvm_vcpu_get_hfar(vcpu), fault_ipa);
+
+ kvm_vcpu_srcu_read_lock(vcpu);
+
+ gfn = fault_ipa >> PAGE_SHIFT;
+
+ memslot = gfn_to_memslot(vcpu->kvm, gfn);
+ hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
+ write_fault = kvm_s390_cur_gmap_fault_is_write(vcpu);
+ if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
+ ret = -ENOEXEC;
+ /*
+ * The guest has put either its instructions or its page-tables
+ * somewhere it shouldn't have. Userspace won't be able to do
+ * anything about this (there's no syndrome for a start).
+ *
+ * Without the relevant sysregs we cannot do anything for now.
+ * Go back to userspace with an error. TODO sysreg handling
+ */
+ if (is_iabt)
+ goto out_unlock;
+
+ if (kvm_vcpu_abt_iss1tw(vcpu)) {
+ /*
+ * Without the relevant sysregs we cannot do anything for now.
+ * Go back to userspace with an error. TODO sysreg handling
+ */
+ goto out_unlock;
+ }
+
+ /*
+ * Check for a cache maintenance operation. Assume the guest is
+ * cautious and skip instruction
+ */
+ if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
+ kvm_incr_pc(vcpu);
+ ret = 1;
+ goto out_unlock;
+ }
+
+ /*
+ * The IPA is reported as [MAX:12], so we need to
+ * complement it with the bottom 12 bits from the
+ * faulting VA. This is always 12 bits, irrespective
+ * of the page size.
+ */
+ fault_ipa |= kvm_vcpu_get_hfar(vcpu) & ((1 << 12) - 1);
+ ret = io_mem_abort(vcpu, fault_ipa);
+ goto out_unlock;
+ }
+
+ /* Userspace should not be able to register out-of-bounds IPAs */
+ VM_BUG_ON(fault_ipa >= vcpu->kvm->arch.guest_phys_size);
+ /*
+ * Proper guest size faults have been injected.
+ * In theory it's fine to have device memory higher than MSL,
+ * even if not currently possible, but that would have been handled above.
+ * So if we get here with a guest size intercept, we have a bug somewhere.
+ */
+ VM_BUG_ON(guest_size_err);
+
+ ret = user_mem_abort(vcpu, fault_ipa, memslot, hva);
+ if (!ret)
+ ret = 1;
+out_unlock:
+ kvm_vcpu_srcu_read_unlock(vcpu);
+ return ret;
+}
+
+long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, struct kvm_pre_fault_memory *range)
+{
+ struct guest_fault f = { .gfn = gpa_to_gfn(range->gpa), };
+ gpa_t end;
+ int rc;
+
+ rc = kvm_s390_faultin_gfn(vcpu, NULL, &f);
+ if (rc == PGM_ADDRESSING)
+ return -ENOENT;
+ if (rc > 0)
+ return -EIO;
+ if (rc < 0)
+ return rc;
+
+ if (f.ptep)
+ return PAGE_SIZE;
+
+ end = ALIGN(range->gpa + PAGE_SIZE, f.crste_region3 ? _REGION3_SIZE : HPAGE_SIZE);
+ return min(range->size, end - range->gpa);
+}
diff --git a/arch/s390/kvm/arm64/trace.h b/arch/s390/kvm/arm64/trace.h
index 0380e45fba28..ee232c4f5a6d 100644
--- a/arch/s390/kvm/arm64/trace.h
+++ b/arch/s390/kvm/arm64/trace.h
@@ -41,6 +41,55 @@ TRACE_EVENT(kvm_exit,
__entry->vcpu_pc)
);
+TRACE_EVENT(kvm_mmio_nisv,
+ TP_PROTO(unsigned long vcpu_pc, unsigned long esr,
+ unsigned long far, unsigned long ipa),
+ TP_ARGS(vcpu_pc, esr, far, ipa),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( unsigned long, esr )
+ __field( unsigned long, far )
+ __field( unsigned long, ipa )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->esr = esr;
+ __entry->far = far;
+ __entry->ipa = ipa;
+ ),
+
+ TP_printk("ipa %#016lx, esr %#016lx, far %#016lx, pc %#016lx",
+ __entry->ipa, __entry->esr,
+ __entry->far, __entry->vcpu_pc)
+);
+
+TRACE_EVENT(kvm_guest_fault,
+ TP_PROTO(unsigned long vcpu_pc, unsigned long hsr,
+ unsigned long hxfar,
+ unsigned long long ipa),
+ TP_ARGS(vcpu_pc, hsr, hxfar, ipa),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( unsigned long, hsr )
+ __field( unsigned long, hxfar )
+ __field( unsigned long long, ipa )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->hsr = hsr;
+ __entry->hxfar = hxfar;
+ __entry->ipa = ipa;
+ ),
+
+ TP_printk("ipa %#llx, hsr %#08lx, hxfar %#08lx, pc %#016lx",
+ __entry->ipa, __entry->hsr,
+ __entry->hxfar, __entry->vcpu_pc)
+);
+
#endif /* KVM_ARM64_TRACE_KVM_H */
#undef TRACE_INCLUDE_PATH
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-09-30 17:34 ` [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler Steffen Eiden
@ 2026-10-01 12:10 ` Arnd Bergmann
2026-10-01 13:35 ` Arnd Bergmann
` (2 more replies)
0 siblings, 3 replies; 36+ messages in thread
From: Arnd Bergmann @ 2026-10-01 12:10 UTC (permalink / raw)
To: Steffen Eiden, kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Catalin Marinas,
Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu,
Lorenzo Stoakes
> + /*
> + * Check for a cache maintenance operation. Assume the guest is
> + * cautious and skip instruction
> + */
> + if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
> + kvm_incr_pc(vcpu);
> + ret = 1;
> + goto out_unlock;
Hi Steffen,
[Adding Lorenzo Stoakes to Cc]
I see this function fails to build on top of linux-next, as the
kvm_vcpu_dabt_is_cm() function was removed by commit 18b94675b1fb
("KVM: arm64: Use ESR helpers in guest abort handling").
I used this patch to make it build, but I'm not sure if this is
the correct fix:
diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
index 3c1c8a2def73..7ee157c61d70 100644
--- a/arch/s390/kvm/arm64/mmu.c
+++ b/arch/s390/kvm/arm64/mmu.c
@@ -119,6 +119,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
write_fault = kvm_s390_cur_gmap_fault_is_write(vcpu);
if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
+ unsigned long esr = kvm_vcpu_get_esr(vcpu);
ret = -ENOEXEC;
/*
* The guest has put either its instructions or its page-tables
@@ -143,7 +144,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
* Check for a cache maintenance operation. Assume the guest is
* cautious and skip instruction
*/
- if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
+ if (kvm_is_error_hva(hva) && esr_dabt_is_cm(esr)) {
kvm_incr_pc(vcpu);
ret = 1;
goto out_unlock;
Arnd
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-10-01 12:10 ` Arnd Bergmann
@ 2026-10-01 13:35 ` Arnd Bergmann
2026-10-01 14:36 ` Lorenzo Stoakes (ARM)
2026-10-01 14:03 ` Steffen Eiden
2026-10-01 14:39 ` Lorenzo Stoakes (ARM)
2 siblings, 1 reply; 36+ messages in thread
From: Arnd Bergmann @ 2026-10-01 13:35 UTC (permalink / raw)
To: Steffen Eiden, kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Catalin Marinas,
Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu,
Lorenzo Stoakes
On Thu, Oct 1, 2026, at 14:10, Arnd Bergmann wrote:
>> + /*
>> + * Check for a cache maintenance operation. Assume the guest is
>> + * cautious and skip instruction
>> + */
>> + if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
>> + kvm_incr_pc(vcpu);
>> + ret = 1;
>> + goto out_unlock;
>
> Hi Steffen,
>
> [Adding Lorenzo Stoakes to Cc]
>
> I see this function fails to build on top of linux-next, as the
> kvm_vcpu_dabt_is_cm() function was removed by commit 18b94675b1fb
> ("KVM: arm64: Use ESR helpers in guest abort handling").
Another ones: after 34cfa9b3af17 ("KVM: arm64: Implement
KVM_PRE_FAULT_MEMORY"), we are now missing a kvm_arch_pre_fault_allowed()
definition in arch/s390/kvm/arm64/mmu.c:
ERROR: modpost: arch/s390/kvm/arm64/kvm-arm64.ko: symbol 'kvm_arch_pre_fault_allowed' undefined!
I copied the arm64 version without the pkvm reference to make it
build for me.
Arnd
diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
index 7ee157c61d70..be16351acaae 100644
--- a/arch/s390/kvm/arm64/mmu.c
+++ b/arch/s390/kvm/arm64/mmu.c
@@ -179,6 +179,14 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
return ret;
}
+int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu)
+{
+ if (!kvm_vcpu_initialized(vcpu))
+ return -ENOEXEC;
+
+ return 0;
+}
+
long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, struct kvm_pre_fault_memory *range)
{
struct guest_fault f = { .gfn = gpa_to_gfn(range->gpa), };
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-10-01 13:35 ` Arnd Bergmann
@ 2026-10-01 14:36 ` Lorenzo Stoakes (ARM)
2026-10-01 15:30 ` Steffen Eiden
0 siblings, 1 reply; 36+ messages in thread
From: Lorenzo Stoakes (ARM) @ 2026-10-01 14:36 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Steffen Eiden, kvm, kvmarm, linux-arm-kernel, linux-kernel,
linux-s390, Alexander Gordeev, Andreas Grapentin,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
On Thu, Oct 01, 2026 at 03:35:37PM +0200, Arnd Bergmann wrote:
> Another ones: after 34cfa9b3af17 ("KVM: arm64: Implement
> KVM_PRE_FAULT_MEMORY"), we are now missing a kvm_arch_pre_fault_allowed()
> definition in arch/s390/kvm/arm64/mmu.c:
>
> ERROR: modpost: arch/s390/kvm/arm64/kvm-arm64.ko: symbol 'kvm_arch_pre_fault_allowed' undefined!
>
> I copied the arm64 version without the pkvm reference to make it
> build for me.
>
> Arnd
>
> diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
> index 7ee157c61d70..be16351acaae 100644
> --- a/arch/s390/kvm/arm64/mmu.c
> +++ b/arch/s390/kvm/arm64/mmu.c
> @@ -179,6 +179,14 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> return ret;
> }
>
> +int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu)
> +{
> + if (!kvm_vcpu_initialized(vcpu))
> + return -ENOEXEC;
> +
> + return 0;
> +}
> +
Ah the s390 <-> kvm emulation stuff.
Yep if it's meant to behave like arm64 then that should be correct.
It's odd to me that pre-faulting was not previously implemented for actual-arm64
but was added as part of the virtualised s390/arm64 thing automatically :)
Not sure if this implementation requires what s390 does with:
+int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu)
+{
+ if (kvm_is_ucontrol(vcpu->kvm))
+ return -EINVAL;
+
+ return 0;
+}
Or both conditions? One for the s390 guys.
--
Cheers, Lorenzo
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-10-01 14:36 ` Lorenzo Stoakes (ARM)
@ 2026-10-01 15:30 ` Steffen Eiden
0 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-10-01 15:30 UTC (permalink / raw)
To: Lorenzo Stoakes (ARM)
Cc: Arnd Bergmann, kvm, kvmarm, linux-arm-kernel, linux-kernel,
linux-s390, Alexander Gordeev, Andreas Grapentin,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
On Thu, Oct 01, 2026 at 03:36:26PM +0100, Lorenzo Stoakes (ARM) wrote:
> On Thu, Oct 01, 2026 at 03:35:37PM +0200, Arnd Bergmann wrote:
> > Another ones: after 34cfa9b3af17 ("KVM: arm64: Implement
> > KVM_PRE_FAULT_MEMORY"), we are now missing a kvm_arch_pre_fault_allowed()
> > definition in arch/s390/kvm/arm64/mmu.c:
> >
> > ERROR: modpost: arch/s390/kvm/arm64/kvm-arm64.ko: symbol 'kvm_arch_pre_fault_allowed' undefined!
> >
> > I copied the arm64 version without the pkvm reference to make it
> > build for me.
> >
> > Arnd
> >
> > diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
> > index 7ee157c61d70..be16351acaae 100644
> > --- a/arch/s390/kvm/arm64/mmu.c
> > +++ b/arch/s390/kvm/arm64/mmu.c
> > @@ -179,6 +179,14 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> > return ret;
> > }
> >
> > +int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu)
> > +{
> > + if (!kvm_vcpu_initialized(vcpu))
> > + return -ENOEXEC;
> > +
> > + return 0;
> > +}
> > +
thanks. This must have slipped through somehow.
>
> Ah the s390 <-> kvm emulation stuff.
no, its not emulation :)
We use a hardware based acclearaion approach.
>
> Yep if it's meant to behave like arm64 then that should be correct.
>
> It's odd to me that pre-faulting was not previously implemented for actual-arm64
> but was added as part of the virtualised s390/arm64 thing automatically :)
>
> Not sure if this implementation requires what s390 does with:
>
> +int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu)
> +{
> + if (kvm_is_ucontrol(vcpu->kvm))
> + return -EINVAL;
no, ucontrol is a feature only for native s390 guests.
kvm_arm64 on s390 always evaluates kvm_is_ucontrol() to false if it
appears in shared (between both s390 KVMs) code.
> +
> + return 0;
> +}
>
> Or both conditions? One for the s390 guys.
>
so just the initialized test.
thanks
Steffen
^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-10-01 12:10 ` Arnd Bergmann
2026-10-01 13:35 ` Arnd Bergmann
@ 2026-10-01 14:03 ` Steffen Eiden
2026-10-01 14:39 ` Lorenzo Stoakes (ARM)
2 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-10-01 14:03 UTC (permalink / raw)
To: Arnd Bergmann
Cc: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390,
Alexander Gordeev, Andreas Grapentin, Catalin Marinas,
Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu,
Lorenzo Stoakes
On Thu, Oct 01, 2026 at 02:10:06PM +0200, Arnd Bergmann wrote:
>
> > + /*
> > + * Check for a cache maintenance operation. Assume the guest is
> > + * cautious and skip instruction
> > + */
> > + if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
> > + kvm_incr_pc(vcpu);
> > + ret = 1;
> > + goto out_unlock;
>
> Hi Steffen,
>
> [Adding Lorenzo Stoakes to Cc]
>
> I see this function fails to build on top of linux-next, as the
> kvm_vcpu_dabt_is_cm() function was removed by commit 18b94675b1fb
> ("KVM: arm64: Use ESR helpers in guest abort handling").
>
> I used this patch to make it build, but I'm not sure if this is
> the correct fix:
>
yes, it is the functional correct fix.
> diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
> index 3c1c8a2def73..7ee157c61d70 100644
> --- a/arch/s390/kvm/arm64/mmu.c
> +++ b/arch/s390/kvm/arm64/mmu.c
> @@ -119,6 +119,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
> write_fault = kvm_s390_cur_gmap_fault_is_write(vcpu);
> if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
> + unsigned long esr = kvm_vcpu_get_esr(vcpu);
move this on top of the function. I need the esr in the function for the
full pfault handling later anyways.
> ret = -ENOEXEC;
> /*
> * The guest has put either its instructions or its page-tables
> @@ -143,7 +144,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> * Check for a cache maintenance operation. Assume the guest is
> * cautious and skip instruction
> */
> - if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
> + if (kvm_is_error_hva(hva) && esr_dabt_is_cm(esr)) {
> kvm_incr_pc(vcpu);
> ret = 1;
> goto out_unlock;
>
Steffen
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler
2026-10-01 12:10 ` Arnd Bergmann
2026-10-01 13:35 ` Arnd Bergmann
2026-10-01 14:03 ` Steffen Eiden
@ 2026-10-01 14:39 ` Lorenzo Stoakes (ARM)
2 siblings, 0 replies; 36+ messages in thread
From: Lorenzo Stoakes (ARM) @ 2026-10-01 14:39 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Steffen Eiden, kvm, kvmarm, linux-arm-kernel, linux-kernel,
linux-s390, Alexander Gordeev, Andreas Grapentin,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Fuad Tabba, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Marc Zyngier, Nico Boehr,
Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
On Thu, Oct 01, 2026 at 02:10:06PM +0200, Arnd Bergmann wrote:
> Hi Steffen,
>
> [Adding Lorenzo Stoakes to Cc]
>
> I see this function fails to build on top of linux-next, as the
> kvm_vcpu_dabt_is_cm() function was removed by commit 18b94675b1fb
> ("KVM: arm64: Use ESR helpers in guest abort handling").
>
> I used this patch to make it build, but I'm not sure if this is
> the correct fix:
>
> diff --git a/arch/s390/kvm/arm64/mmu.c b/arch/s390/kvm/arm64/mmu.c
> index 3c1c8a2def73..7ee157c61d70 100644
> --- a/arch/s390/kvm/arm64/mmu.c
> +++ b/arch/s390/kvm/arm64/mmu.c
> @@ -119,6 +119,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
> write_fault = kvm_s390_cur_gmap_fault_is_write(vcpu);
> if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
> + unsigned long esr = kvm_vcpu_get_esr(vcpu);
> ret = -ENOEXEC;
> /*
> * The guest has put either its instructions or its page-tables
> @@ -143,7 +144,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu)
> * Check for a cache maintenance operation. Assume the guest is
> * cautious and skip instruction
> */
> - if (kvm_is_error_hva(hva) && kvm_vcpu_dabt_is_cm(vcpu)) {
> + if (kvm_is_error_hva(hva) && esr_dabt_is_cm(esr)) {
> kvm_incr_pc(vcpu);
> ret = 1;
> goto out_unlock;
Thanks for the report!
The original function was:
static inline bool kvm_vcpu_dabt_is_cm(const struct kvm_vcpu *vcpu)
{
return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_CM);
}
And esr_dabt_is_cm() is:
static __always_inline bool esr_dabt_is_cm(unsigned long esr)
{
return esr & ESR_ELx_CM;
}
So looks good to me at a glance!
--
Cheers, Lorenzo
^ permalink raw reply [flat|nested] 36+ messages in thread
* [PATCH v9 24/24] KVM: s390: arm64: Integrate arm on s390
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (22 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 23/24] KVM: s390: arm64: Implement basic page fault handler Steffen Eiden
@ 2026-09-30 17:34 ` Steffen Eiden
2026-10-01 11:04 ` (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Marc Zyngier
24 siblings, 0 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-09-30 17:34 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Fuad Tabba, Gautam Gala,
Hariharan Mari, Heiko Carstens, Hendrik Brueckner,
Ilya Leoshkevich, Janosch Frank, Joey Gouly, Marc Zyngier,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu
Add all Kbuild/Makefile configurations to build a second KVM module on
s390 implementing the arm64 KVM API. The new module is named kvm_arm64.
Symbol conflicts with kvm_s390 are prevented by localising all internal
symbols in kvm_arm64 when compiled as built-in (=y): kvm-unnamespaced.o
holds all constituent objects. objcopy --localize-symbols then produces
kvm-namespaced.o which is what kvm-arm64.o resolves to. For =m the
normal module symbol scoping applies and no localisation step is needed.
Because the %-arm64.o pattern targets do not match any kvm-arm64-y entry,
kbuild would derive a wrong KBUILD_MODNAME (e.g. "kvm_main_arm64") and
a wrong KBUILD_MODFILE for the virt/kvm and gmap copies.
Co-developed-by: Andreas Grapentin <gra@linux.ibm.com>
Signed-off-by: Andreas Grapentin <gra@linux.ibm.com>
Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Co-developed-by: Gautam Gala <ggala@linux.ibm.com>
Signed-off-by: Gautam Gala <ggala@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/kvm/Kconfig | 25 +++++---
arch/s390/kvm/Makefile | 1 +
arch/s390/kvm/arm64/Makefile | 110 +++++++++++++++++++++++++++++++++++
3 files changed, 127 insertions(+), 9 deletions(-)
create mode 100644 arch/s390/kvm/arm64/Makefile
diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
index 9045ae20fd89..e7b525d04c6d 100644
--- a/arch/s390/kvm/Kconfig
+++ b/arch/s390/kvm/Kconfig
@@ -30,15 +30,22 @@ config KVM
select KVM_MMU_LOCKLESS_AGING
select KVM_GENERIC_PRE_FAULT_MEMORY
help
- Support hosting paravirtualized guest machines using the SIE
- virtualization capability on the mainframe. This should work
- on any 64bit machine.
-
- This module provides access to the hardware capabilities through
- a character device node named /dev/kvm.
-
- To compile this as a module, choose M here: the module
- will be called kvm.
+ Enable support for hosting virtualized, hardware-accelerated
+ virtual machines via two modules: kvm and kvm_arm64.
+
+ The kvm module provides access to host hardware-accelerated s390
+ guests using the Start Interpretive Execution (SIE) instruction via a
+ character device node named /dev/kvm. This requires a 64-bit machine
+ (hardware model).
+
+ The kvm_arm64 module provides access to host hardware-accelerated
+ arm64 guests using the Start ARM Execution (SAE) instruction via a
+ character device node named /dev/kvm_arm64. This requires hardware
+ models that support the Arm execution facility (AEF).
+
+ To compile this driver as a module, choose M here. The module will be
+ called kvm for the SIE acceleration and kvm_arm64 for the SAE
+ acceleration.
If unsure, say N.
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index a4e3875b5bdd..380db443a0e9 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -4,3 +4,4 @@
# Copyright IBM Corp. 2008
obj-$(CONFIG_KVM) += s390/
+obj-$(CONFIG_KVM) += arm64/
diff --git a/arch/s390/kvm/arm64/Makefile b/arch/s390/kvm/arm64/Makefile
new file mode 100644
index 000000000000..3f0fe5c9f0a1
--- /dev/null
+++ b/arch/s390/kvm/arm64/Makefile
@@ -0,0 +1,110 @@
+# SPDX-License-Identifier: GPL-2.0
+
+KVM := ../../../../virt/kvm
+KVM_DEV_NAME = kvm_arm64
+KVM_DEV_MINOR = MISC_DYNAMIC_MINOR
+include $(srctree)/virt/kvm/Makefile.kvm
+include $(srctree)/arch/$(SRCARCH)/kvm/gmap/Makefile
+include $(src)/Makefile.gen
+
+ccflags-y += -I $(src) -I $(objtree)/$(obj) -I$(srctree)/arch/$(SRCARCH)/kvm/gmap -DKVM_S390_ARM64
+
+kvm-arm64-local := \
+ arm.o \
+ guest.o \
+ handle_exit.o \
+ inject_fault.o \
+ mmio.o \
+ mmu.o \
+ reset.o
+
+kvm-arm64-obj := $(kvm-arm64-local)
+kvm-arm64-obj += $(patsubst %.o,%-arm64.o,$(kvm-y))
+kvm-arm64-obj += $(patsubst %.o,%-arm64.o,$(gmap-y))
+
+targets += $(kvm-arm64-obj)
+
+$(obj)/%-arm64.o: $(src)/%.c FORCE
+ @mkdir -p $(dir $@)
+ $(call if_changed_rule,cc_o_c)
+ $(call cmd,force_checksrc)
+
+# %-arm64.o stems don't match any kvm-arm64-y entry so Kbuild derives wrong
+# KBUILD_MODNAME/KBUILD_MODFILE. Force include a generated header to override.
+KVM_ARM64_MODNAME_H := $(obj)/generated/kvm_arm64_modname.h
+ccflags-y += -include $(KVM_ARM64_MODNAME_H)
+
+$(addprefix $(obj)/,$(kvm-arm64-obj)): $(KVM_ARM64_MODNAME_H)
+$(foreach sfx, i s ll lst, \
+ $(eval $(patsubst %.o,%.$(sfx),$(addprefix $(obj)/,$(kvm-arm64-local))): $(KVM_ARM64_MODNAME_H)))
+
+targets += generated/kvm_arm64_modname.h
+
+define filechk_kvm_arm64_modname
+ echo '#ifndef __KVM_ARM64_MODNAME_H'; \
+ echo '#define __KVM_ARM64_MODNAME_H'; \
+ echo '#undef KBUILD_MODNAME'; \
+ echo '#define KBUILD_MODNAME "$(KVM_DEV_NAME)"'; \
+ echo '#undef __KBUILD_MODNAME'; \
+ echo '#define __KBUILD_MODNAME $(KVM_DEV_NAME)'; \
+ echo '#undef KBUILD_MODFILE'; \
+ echo '#define KBUILD_MODFILE "$(obj)/kvm-arm64"'; \
+ echo '#endif /* __KVM_ARM64_MODNAME_H */'
+endef
+
+$(KVM_ARM64_MODNAME_H): FORCE
+ $(call filechk,kvm_arm64_modname)
+
+# Members are not in real-obj-y. Set part-of-builtin to enable instrumentation.
+$(addprefix $(obj)/,$(kvm-arm64-obj)): private part-of-builtin := y
+
+ifeq ($(CONFIG_KVM),m)
+
+kvm-arm64-y = $(kvm-arm64-obj)
+
+else ifeq ($(CONFIG_KVM),y)
+
+prereq-o-cmd = $(foreach o, $(filter %.o, $^), $(dir $(o)).$(notdir $(o)).cmd)
+cmd_gen_symversions_o = \
+ grep --no-filename "^\#SYMVER" $(prereq-o-cmd) >> $(dot-target).cmd || true
+
+cmd_ld_o_o = $(cmd_ld)
+define rule_ld_o_o
+ $(call cmd_and_savecmd,ld)
+ $(call cmd,gen_symversions_o)
+endef
+
+LDFLAGS_kvm-unnamespaced.o := -r
+$(obj)/kvm-unnamespaced.o: $(addprefix $(obj)/,$(kvm-arm64-obj)) FORCE
+ $(call if_changed_rule,ld_o_o)
+
+quiet_cmd_nm_filter = NMFLTR $@
+ cmd_nm_filter = $(NM) --defined-only --format=just-symbols $< | sort -u > $@
+
+$(obj)/kvm_symbol_list: $(obj)/kvm-unnamespaced.o FORCE
+ $(call if_changed,nm_filter)
+
+# cmd_oc_o_o carries -DKBUILD_MODFILE so generate_builtin_ranges.awk
+# can attribute kvm-namespaced.o to kvm_arm64 via its .cmd file.
+cmd_oc_o_o = $(cmd_objcopy) -DKBUILD_MODFILE='"$(obj)/kvm-arm64"'
+define rule_oc_o_o
+ $(call cmd,objcopy)
+ @printf '%s\n' 'savedcmd_$@ := $(call make-cmd,oc_o_o)' > $(dot-target).cmd
+ $(call cmd,gen_objtooldep)
+ $(call cmd,gen_symversions_o)
+endef
+
+OBJCOPYFLAGS_kvm-namespaced.o := -O $(LD_BFD) --localize-symbols=$(obj)/kvm_symbol_list
+$(obj)/kvm-namespaced.o: $(obj)/kvm-unnamespaced.o $(obj)/kvm_symbol_list FORCE
+ $(call if_changed_rule,oc_o_o)
+
+kvm-arm64-y = kvm-namespaced.o
+
+targets += kvm-unnamespaced.o kvm_symbol_list kvm-namespaced.o
+
+endif
+
+clean-files += kvm-unnamespaced.o kvm_symbol_list kvm-namespaced.o
+
+obj-$(CONFIG_KVM) += kvm-arm64.o
+
--
2.53.0
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM
2026-09-30 17:34 [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Steffen Eiden
` (23 preceding siblings ...)
2026-09-30 17:34 ` [PATCH v9 24/24] KVM: s390: arm64: Integrate arm on s390 Steffen Eiden
@ 2026-10-01 11:04 ` Marc Zyngier
2026-10-01 13:27 ` Steffen Eiden
24 siblings, 1 reply; 36+ messages in thread
From: Marc Zyngier @ 2026-10-01 11:04 UTC (permalink / raw)
To: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390, Steffen Eiden
Cc: Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Nico Boehr, Nina Schoetterl-Glausch,
Oliver Upton, Paolo Bonzini, Sean Christopherson,
Suzuki K Poulose, Sven Schnelle, Ulrich Weigand, Vasily Gorbik,
Will Deacon, Zenghui Yu, Fuad Tabba
On Wed, 30 Sep 2026 19:34:15 +0200, Steffen Eiden wrote:
> Introduce arm-on-s390. Enable KVM-accelerated ARM CPU virtualisation on s390.
>
> The new KVM functionally depends on KVM/vfio: Use file-based reference
> counting for KVM [5] The series itself should apply w/o those.
>
> For the original, now partially outdated, cover letter, have a look at versions
> one to three [1].
>
> [...]
Applied to next, thanks!
[05/24] arm64: ptrace: Use constants for compat register numbers
commit: 295d3df9b1e425099a4eb37954a02c4a08fdb496
[06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation
commit: d3d78520068779779e1ed7aa0dd8a3ce63e1ca43
[07/24] KVM: arm64: Access elements of vcpu_gp_regs individually
commit: 29d92585ab987bb80b1e78d811aaea2a8db86e62
[08/24] KVM: arm64: Use accessor functions for core regs
commit: 89ed62818f10e38e64fea46d43ee6455a1beb647
[09/24] arm64: Prepare sharing arm64 headers with s390
commit: df6a70516adec8b7f5fa49e1755d8ee33d980d9c
[10/24] arm64: Share arm64 headers with s390
commit: c7e18ba462536e870b0ff4deca581babcac9135b
[11/24] KVM: arm64: Share arm64 code with s390
commit: dcb776bfcccc9662001a75b99dbfbef55f46eb31
Note that there were a few conflicts. Please check that I resolved
them correctly.
Cheers,
M.
--
Without deviation from the norm, progress is not possible.
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM
2026-10-01 11:04 ` (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM Marc Zyngier
@ 2026-10-01 13:27 ` Steffen Eiden
2026-10-01 13:39 ` Arnd Bergmann
2026-10-01 15:12 ` Marc Zyngier
0 siblings, 2 replies; 36+ messages in thread
From: Steffen Eiden @ 2026-10-01 13:27 UTC (permalink / raw)
To: Marc Zyngier
Cc: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390,
Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Nico Boehr, Nina Schoetterl-Glausch,
Oliver Upton, Paolo Bonzini, Sean Christopherson,
Suzuki K Poulose, Sven Schnelle, Ulrich Weigand, Vasily Gorbik,
Will Deacon, Zenghui Yu, Fuad Tabba
On Thu, Oct 01, 2026 at 12:04:51PM +0100, Marc Zyngier wrote:
> On Wed, 30 Sep 2026 19:34:15 +0200, Steffen Eiden wrote:
> > Introduce arm-on-s390. Enable KVM-accelerated ARM CPU virtualisation on s390.
> >
> > The new KVM functionally depends on KVM/vfio: Use file-based reference
> > counting for KVM [5] The series itself should apply w/o those.
> >
> > For the original, now partially outdated, cover letter, have a look at versions
> > one to three [1].
> >
> > [...]
>
> Applied to next, thanks!
>
> [05/24] arm64: ptrace: Use constants for compat register numbers
> commit: 295d3df9b1e425099a4eb37954a02c4a08fdb496
> [06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation
> commit: d3d78520068779779e1ed7aa0dd8a3ce63e1ca43
> [07/24] KVM: arm64: Access elements of vcpu_gp_regs individually
> commit: 29d92585ab987bb80b1e78d811aaea2a8db86e62
> [08/24] KVM: arm64: Use accessor functions for core regs
> commit: 89ed62818f10e38e64fea46d43ee6455a1beb647
> [09/24] arm64: Prepare sharing arm64 headers with s390
> commit: df6a70516adec8b7f5fa49e1755d8ee33d980d9c
> [10/24] arm64: Share arm64 headers with s390
> commit: c7e18ba462536e870b0ff4deca581babcac9135b
> [11/24] KVM: arm64: Share arm64 code with s390
> commit: dcb776bfcccc9662001a75b99dbfbef55f46eb31
>
> Note that there were a few conflicts. Please check that I resolved
> them correctly.
After rebasing on those the arm-on-s390 part does not build anymore :(
We are missing the definition of
static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
quick fix:
on top of [10/24] arm64: Share arm64 headers with s390
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index bf35cbe8ddcb..0708f792c631 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -367,10 +367,13 @@ static __always_inline u64 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
return vcpu->arch.fault.esr_el2;
}
+#if ARM64_S390_COMMON == 1
static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
{
return esr & ESR_ELx_S1PTW;
}
+
+#endif /* ARM64_S390_COMMON == 1 */
static __always_inline bool esr_abt_is_exec_fault(unsigned long esr)
{
A cleaner solution it to move this defenition just below
void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) in
[09/24] arm64: Prepare sharing arm64 headers with s390
and expand the shared region in the following patch.
I can send the two fixup patches as a reply here for this tomorrow or later today if you want.
Steffen
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM
2026-10-01 13:27 ` Steffen Eiden
@ 2026-10-01 13:39 ` Arnd Bergmann
2026-10-01 15:12 ` Marc Zyngier
1 sibling, 0 replies; 36+ messages in thread
From: Arnd Bergmann @ 2026-10-01 13:39 UTC (permalink / raw)
To: Steffen Eiden, Marc Zyngier
Cc: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390,
Alexander Gordeev, Andreas Grapentin, Catalin Marinas,
Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand (Red Hat),
Friedrich Welter, Gautam Gala, Hariharan Mari, Heiko Carstens,
Hendrik Brueckner, Ilya Leoshkevich, Janosch Frank, Joey Gouly,
Nico Boehr, Nina Schoetterl-Glausch, Oliver Upton, Paolo Bonzini,
Sean Christopherson, Suzuki K Poulose, Sven Schnelle,
Ulrich Weigand, Vasily Gorbik, Will Deacon, Zenghui Yu,
Fuad Tabba
On Thu, Oct 1, 2026, at 15:27, Steffen Eiden wrote:
> On Thu, Oct 01, 2026 at 12:04:51PM +0100, Marc Zyngier wrote:
>
> quick fix:
Ah, I was about to send the same thing.
> I can send the two fixup patches as a reply here for this tomorrow or
> later today if you want.
My build bot is churning away looking for more corner cases.
I initially had the wrong base, but with this one and the other
two I sent, things are starting to look good. I'll keep it
running over night, but if you don't hear from me for any additional
build regressions in the next hour, it's probably fine.
Arnd
^ permalink raw reply [flat|nested] 36+ messages in thread* Re: (subset) [PATCH v9 00/24] KVM: s390: Introduce arm64 KVM
2026-10-01 13:27 ` Steffen Eiden
2026-10-01 13:39 ` Arnd Bergmann
@ 2026-10-01 15:12 ` Marc Zyngier
1 sibling, 0 replies; 36+ messages in thread
From: Marc Zyngier @ 2026-10-01 15:12 UTC (permalink / raw)
To: Steffen Eiden
Cc: kvm, kvmarm, linux-arm-kernel, linux-kernel, linux-s390,
Alexander Gordeev, Andreas Grapentin, Arnd Bergmann,
Catalin Marinas, Christian Borntraeger, Claudio Imbrenda,
David Hildenbrand, Friedrich Welter, Gautam Gala, Hariharan Mari,
Heiko Carstens, Hendrik Brueckner, Ilya Leoshkevich,
Janosch Frank, Joey Gouly, Nico Boehr, Nina Schoetterl-Glausch,
Oliver Upton, Paolo Bonzini, Sean Christopherson,
Suzuki K Poulose, Sven Schnelle, Ulrich Weigand, Vasily Gorbik,
Will Deacon, Zenghui Yu, Fuad Tabba
On Thu, 01 Oct 2026 14:27:15 +0100,
Steffen Eiden <seiden@linux.ibm.com> wrote:
>
> On Thu, Oct 01, 2026 at 12:04:51PM +0100, Marc Zyngier wrote:
> > On Wed, 30 Sep 2026 19:34:15 +0200, Steffen Eiden wrote:
> > > Introduce arm-on-s390. Enable KVM-accelerated ARM CPU virtualisation on s390.
> > >
> > > The new KVM functionally depends on KVM/vfio: Use file-based reference
> > > counting for KVM [5] The series itself should apply w/o those.
> > >
> > > For the original, now partially outdated, cover letter, have a look at versions
> > > one to three [1].
> > >
> > > [...]
> >
> > Applied to next, thanks!
> >
> > [05/24] arm64: ptrace: Use constants for compat register numbers
> > commit: 295d3df9b1e425099a4eb37954a02c4a08fdb496
> > [06/24] arm64: sysreg: Convert SPSR_ELx to automatic register generation
> > commit: d3d78520068779779e1ed7aa0dd8a3ce63e1ca43
> > [07/24] KVM: arm64: Access elements of vcpu_gp_regs individually
> > commit: 29d92585ab987bb80b1e78d811aaea2a8db86e62
> > [08/24] KVM: arm64: Use accessor functions for core regs
> > commit: 89ed62818f10e38e64fea46d43ee6455a1beb647
> > [09/24] arm64: Prepare sharing arm64 headers with s390
> > commit: df6a70516adec8b7f5fa49e1755d8ee33d980d9c
> > [10/24] arm64: Share arm64 headers with s390
> > commit: c7e18ba462536e870b0ff4deca581babcac9135b
> > [11/24] KVM: arm64: Share arm64 code with s390
> > commit: dcb776bfcccc9662001a75b99dbfbef55f46eb31
> >
> > Note that there were a few conflicts. Please check that I resolved
> > them correctly.
>
>
> After rebasing on those the arm-on-s390 part does not build anymore :(
Well, that's sort of expected. The kvmarm tree doesn't have the S390
stuff yet, and contains tons of new stuff.
> We are missing the definition of
> static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
>
>
> quick fix:
>
> on top of [10/24] arm64: Share arm64 headers with s390
>
> diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
> index bf35cbe8ddcb..0708f792c631 100644
> --- a/arch/arm64/include/asm/kvm_emulate.h
> +++ b/arch/arm64/include/asm/kvm_emulate.h
> @@ -367,10 +367,13 @@ static __always_inline u64 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
> return vcpu->arch.fault.esr_el2;
> }
>
> +#if ARM64_S390_COMMON == 1
> static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
> {
> return esr & ESR_ELx_S1PTW;
> }
> +
> +#endif /* ARM64_S390_COMMON == 1 */
>
> static __always_inline bool esr_abt_is_exec_fault(unsigned long esr)
> {
>
>
>
> A cleaner solution it to move this defenition just below
> void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) in
> [09/24] arm64: Prepare sharing arm64 headers with s390
> and expand the shared region in the following patch.
I'm redoing the merge and fixing it as follows (note that the
ARM64_S390_COMMON guards are already present):
@@ -336,16 +367,6 @@ static __always_inline u64 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
return vcpu->arch.fault.esr_el2;
}
-static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
-{
- return esr & ESR_ELx_S1PTW;
-}
-
-static __always_inline bool esr_abt_is_exec_fault(unsigned long esr)
-{
- return esr_trap_is_iabt(esr) && !esr_abt_is_s1ptw(esr);
-}
-
static inline bool guest_hyp_wfx_traps_enabled(const struct kvm_vcpu *vcpu)
{
u64 esr = kvm_vcpu_get_esr(vcpu);
@@ -389,6 +410,12 @@ static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
return vcpu->arch.fault.disr_el1;
}
+#if ARM64_S390_COMMON == 1
+static __always_inline bool esr_abt_is_s1ptw(unsigned long esr)
+{
+ return esr & ESR_ELx_S1PTW;
+}
+
static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
{
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_xVC_IMM_MASK;
@@ -456,6 +483,13 @@ static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC;
}
+#endif /* ARM64_S390_COMMON == 1 */
+
+static __always_inline bool esr_abt_is_exec_fault(unsigned long esr)
+{
+ return esr_trap_is_iabt(esr) && !esr_abt_is_s1ptw(esr);
+}
+
static inline
bool kvm_vcpu_trap_is_permission_fault(const struct kvm_vcpu *vcpu)
{
Does this work for you?
M.
--
Without deviation from the norm, progress is not possible.
^ permalink raw reply [flat|nested] 36+ messages in thread