[PATCH 0/2] KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal

[PATCH 0/2] KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal

[Vitaly Kuznetsov]

Commit 6dac1195181c ("KVM: selftests: Make Hyper-V tests explicitly require
KVM Hyper-V support") wrongfully added KVM_CAP_HYPERV_DIRECT_TLBFLUSH
requirement to hyperv_evmcs/hyperv_svm_test tests. The capability is only set
when KVM runs on top of Hyper-V. The result is that both tests just skip when
launched on bare metal. Add the required infrastructure and check for the
correct CPUID bit in KVM_GET_SUPPORTED_HV_CPUID instead.

Vitaly Kuznetsov (2):
  KVM: selftests: Move Hyper-V specific functions out of processor.c
  KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal

 .../selftests/kvm/include/x86_64/hyperv.h     | 18 +++++
 .../selftests/kvm/include/x86_64/processor.h  |  7 +-
 .../testing/selftests/kvm/lib/x86_64/hyperv.c | 67 +++++++++++++++++++
 .../selftests/kvm/lib/x86_64/processor.c      | 61 -----------------
 .../selftests/kvm/x86_64/hyperv_evmcs.c       |  2 +-
 .../selftests/kvm/x86_64/hyperv_svm_test.c    |  2 +-
 .../selftests/kvm/x86_64/xen_vmcall_test.c    |  1 +
 7 files changed, 92 insertions(+), 66 deletions(-)

-- 
2.46.0

[PATCH 1/2] KVM: selftests: Move Hyper-V specific functions out of processor.c

[Vitaly Kuznetsov]

Since there is 'hyperv.c' for Hyper-V specific functions already, move
Hyper-V specific functions out of processor.c there.

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 .../selftests/kvm/include/x86_64/hyperv.h     |  4 ++
 .../selftests/kvm/include/x86_64/processor.h  |  7 ++-
 .../testing/selftests/kvm/lib/x86_64/hyperv.c | 59 ++++++++++++++++++
 .../selftests/kvm/lib/x86_64/processor.c      | 61 -------------------
 .../selftests/kvm/x86_64/xen_vmcall_test.c    |  1 +
 5 files changed, 68 insertions(+), 64 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index fa65b908b13e..a2e7cf7ee0ad 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -343,4 +343,8 @@ struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
 /* HV_X64_MSR_TSC_INVARIANT_CONTROL bits */
 #define HV_INVARIANT_TSC_EXPOSED               BIT_ULL(0)
 
+const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void);
+const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu);
+void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu);
+
 #endif /* !SELFTEST_KVM_HYPERV_H */
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index a0c1440017bb..e247f99e0473 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -25,6 +25,10 @@ extern bool host_cpu_is_intel;
 extern bool host_cpu_is_amd;
 extern uint64_t guest_tsc_khz;
 
+#ifndef MAX_NR_CPUID_ENTRIES
+#define MAX_NR_CPUID_ENTRIES 100
+#endif
+
 /* Forced emulation prefix, used to invoke the emulator unconditionally. */
 #define KVM_FEP "ud2; .byte 'k', 'v', 'm';"
 
@@ -908,8 +912,6 @@ static inline void vcpu_xcrs_set(struct kvm_vcpu *vcpu, struct kvm_xcrs *xcrs)
 const struct kvm_cpuid_entry2 *get_cpuid_entry(const struct kvm_cpuid2 *cpuid,
 					       uint32_t function, uint32_t index);
 const struct kvm_cpuid2 *kvm_get_supported_cpuid(void);
-const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void);
-const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu);
 
 static inline uint32_t kvm_cpu_fms(void)
 {
@@ -1009,7 +1011,6 @@ static inline struct kvm_cpuid2 *allocate_kvm_cpuid2(int nr_entries)
 }
 
 void vcpu_init_cpuid(struct kvm_vcpu *vcpu, const struct kvm_cpuid2 *cpuid);
-void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu);
 
 static inline struct kvm_cpuid_entry2 *__vcpu_get_cpuid_entry(struct kvm_vcpu *vcpu,
 							      uint32_t function,
diff --git a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
index efb7e7a1354d..b4a5e4ad7105 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
@@ -8,6 +8,65 @@
 #include "processor.h"
 #include "hyperv.h"
 
+const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void)
+{
+	static struct kvm_cpuid2 *cpuid;
+	int kvm_fd;
+
+	if (cpuid)
+		return cpuid;
+
+	cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
+	kvm_fd = open_kvm_dev_path_or_exit();
+
+	kvm_ioctl(kvm_fd, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
+
+	close(kvm_fd);
+	return cpuid;
+}
+
+void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu)
+{
+	static struct kvm_cpuid2 *cpuid_full;
+	const struct kvm_cpuid2 *cpuid_sys, *cpuid_hv;
+	int i, nent = 0;
+
+	if (!cpuid_full) {
+		cpuid_sys = kvm_get_supported_cpuid();
+		cpuid_hv = kvm_get_supported_hv_cpuid();
+
+		cpuid_full = allocate_kvm_cpuid2(cpuid_sys->nent + cpuid_hv->nent);
+		if (!cpuid_full) {
+			perror("malloc");
+			abort();
+		}
+
+		/* Need to skip KVM CPUID leaves 0x400000xx */
+		for (i = 0; i < cpuid_sys->nent; i++) {
+			if (cpuid_sys->entries[i].function >= 0x40000000 &&
+			    cpuid_sys->entries[i].function < 0x40000100)
+				continue;
+			cpuid_full->entries[nent] = cpuid_sys->entries[i];
+			nent++;
+		}
+
+		memcpy(&cpuid_full->entries[nent], cpuid_hv->entries,
+		       cpuid_hv->nent * sizeof(struct kvm_cpuid_entry2));
+		cpuid_full->nent = nent + cpuid_hv->nent;
+	}
+
+	vcpu_init_cpuid(vcpu, cpuid_full);
+}
+
+const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu)
+{
+	struct kvm_cpuid2 *cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
+
+	vcpu_ioctl(vcpu, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
+
+	return cpuid;
+}
+
 struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
 						       vm_vaddr_t *p_hv_pages_gva)
 {
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 153739f2e201..7876f052ca39 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -19,8 +19,6 @@
 #define KERNEL_DS	0x10
 #define KERNEL_TSS	0x18
 
-#define MAX_NR_CPUID_ENTRIES 100
-
 vm_vaddr_t exception_handlers;
 bool host_cpu_is_amd;
 bool host_cpu_is_intel;
@@ -1195,65 +1193,6 @@ void xen_hypercall(uint64_t nr, uint64_t a0, void *a1)
 	GUEST_ASSERT(!__xen_hypercall(nr, a0, a1));
 }
 
-const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void)
-{
-	static struct kvm_cpuid2 *cpuid;
-	int kvm_fd;
-
-	if (cpuid)
-		return cpuid;
-
-	cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
-	kvm_fd = open_kvm_dev_path_or_exit();
-
-	kvm_ioctl(kvm_fd, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
-
-	close(kvm_fd);
-	return cpuid;
-}
-
-void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu)
-{
-	static struct kvm_cpuid2 *cpuid_full;
-	const struct kvm_cpuid2 *cpuid_sys, *cpuid_hv;
-	int i, nent = 0;
-
-	if (!cpuid_full) {
-		cpuid_sys = kvm_get_supported_cpuid();
-		cpuid_hv = kvm_get_supported_hv_cpuid();
-
-		cpuid_full = allocate_kvm_cpuid2(cpuid_sys->nent + cpuid_hv->nent);
-		if (!cpuid_full) {
-			perror("malloc");
-			abort();
-		}
-
-		/* Need to skip KVM CPUID leaves 0x400000xx */
-		for (i = 0; i < cpuid_sys->nent; i++) {
-			if (cpuid_sys->entries[i].function >= 0x40000000 &&
-			    cpuid_sys->entries[i].function < 0x40000100)
-				continue;
-			cpuid_full->entries[nent] = cpuid_sys->entries[i];
-			nent++;
-		}
-
-		memcpy(&cpuid_full->entries[nent], cpuid_hv->entries,
-		       cpuid_hv->nent * sizeof(struct kvm_cpuid_entry2));
-		cpuid_full->nent = nent + cpuid_hv->nent;
-	}
-
-	vcpu_init_cpuid(vcpu, cpuid_full);
-}
-
-const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid2 *cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
-
-	vcpu_ioctl(vcpu, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
-
-	return cpuid;
-}
-
 unsigned long vm_compute_max_gfn(struct kvm_vm *vm)
 {
 	const unsigned long num_ht_pages = 12 << (30 - vm->page_shift); /* 12 GiB */
diff --git a/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c b/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
index e149d0574961..2585087cdf5c 100644
--- a/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
@@ -10,6 +10,7 @@
 #include "test_util.h"
 #include "kvm_util.h"
 #include "processor.h"
+#include "hyperv.h"
 
 #define HCALL_REGION_GPA	0xc0000000ULL
 #define HCALL_REGION_SLOT	10
-- 
2.46.0

[PATCH 2/2] KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal

[Vitaly Kuznetsov]

KVM_CAP_HYPERV_DIRECT_TLBFLUSH is only reported when KVM runs on top of
Hyper-V and hyperv_evmcs/hyperv_svm_test don't need that, these tests check
that the feature is properly emulated for Hyper-V on KVM guests. There's no
corresponding CAP for that, the feature is reported in
KVM_GET_SUPPORTED_HV_CPUID.

Hyper-V specific CPUIDs are not reported by KVM_GET_SUPPORTED_CPUID,
implement dedicated kvm_hv_cpu_has() helper to do the job.

Fixes: 6dac1195181c ("KVM: selftests: Make Hyper-V tests explicitly require KVM Hyper-V support")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 .../testing/selftests/kvm/include/x86_64/hyperv.h  | 14 ++++++++++++++
 tools/testing/selftests/kvm/lib/x86_64/hyperv.c    |  8 ++++++++
 tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c  |  2 +-
 .../testing/selftests/kvm/x86_64/hyperv_svm_test.c |  2 +-
 4 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index a2e7cf7ee0ad..6849e2552f1b 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -186,6 +186,18 @@
 #define HV_X64_ENLIGHTENED_VMCS_RECOMMENDED		\
 	KVM_X86_CPU_FEATURE(HYPERV_CPUID_ENLIGHTMENT_INFO, 0, EAX, 14)
 
+/* HYPERV_CPUID_NESTED_FEATURES.EAX */
+#define HV_X64_NESTED_DIRECT_FLUSH			\
+	KVM_X86_CPU_FEATURE(HYPERV_CPUID_NESTED_FEATURES, 0, EAX, 17)
+#define HV_X64_NESTED_GUEST_MAPPING_FLUSH		\
+	KVM_X86_CPU_FEATURE(HYPERV_CPUID_NESTED_FEATURES, 0, EAX, 18)
+#define HV_X64_NESTED_MSR_BITMAP			\
+	KVM_X86_CPU_FEATURE(HYPERV_CPUID_NESTED_FEATURES, 0, EAX, 19)
+
+/* HYPERV_CPUID_NESTED_FEATURES.EBX */
+#define HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL		\
+	KVM_X86_CPU_FEATURE(HYPERV_CPUID_NESTED_FEATURES, 0, EBX, 0)
+
 /* HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES.EAX */
 #define HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING	\
 	KVM_X86_CPU_FEATURE(HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES, 0, EAX, 1)
@@ -347,4 +359,6 @@ const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void);
 const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu);
 void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu);
 
+bool kvm_hv_cpu_has(struct kvm_x86_cpu_feature feature);
+
 #endif /* !SELFTEST_KVM_HYPERV_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
index b4a5e4ad7105..15bc8cd583aa 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
@@ -67,6 +67,14 @@ const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu)
 	return cpuid;
 }
 
+bool kvm_hv_cpu_has(struct kvm_x86_cpu_feature feature)
+{
+	if (!kvm_has_cap(KVM_CAP_SYS_HYPERV_CPUID))
+		return false;
+
+	return kvm_cpuid_has(kvm_get_supported_hv_cpuid(), feature);
+}
+
 struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
 						       vm_vaddr_t *p_hv_pages_gva)
 {
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c b/tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c
index e192720bfe14..74cf19661309 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c
@@ -242,7 +242,7 @@ int main(int argc, char *argv[])
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_NESTED_STATE));
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS));
-	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_DIRECT_TLBFLUSH));
+	TEST_REQUIRE(kvm_hv_cpu_has(HV_X64_NESTED_DIRECT_FLUSH));
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index b987a3d79715..0ddb63229bcb 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -157,7 +157,7 @@ int main(int argc, char *argv[])
 	int stage;
 
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM));
-	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_DIRECT_TLBFLUSH));
+	TEST_REQUIRE(kvm_hv_cpu_has(HV_X64_NESTED_DIRECT_FLUSH));
 
 	/* Create VM */
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
-- 
2.46.0

Re: [PATCH 0/2] KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal

[Sean Christopherson]

On Fri, 16 Aug 2024 15:01:37 +0200, Vitaly Kuznetsov wrote:
> Commit 6dac1195181c ("KVM: selftests: Make Hyper-V tests explicitly require
> KVM Hyper-V support") wrongfully added KVM_CAP_HYPERV_DIRECT_TLBFLUSH
> requirement to hyperv_evmcs/hyperv_svm_test tests. The capability is only set
> when KVM runs on top of Hyper-V. The result is that both tests just skip when
> launched on bare metal. Add the required infrastructure and check for the
> correct CPUID bit in KVM_GET_SUPPORTED_HV_CPUID instead.
> 
> [...]

Applied to kvm-x86 selftests, thanks!

[1/2] KVM: selftests: Move Hyper-V specific functions out of processor.c
      https://github.com/kvm-x86/linux/commit/24a7e944966c
[2/2] KVM: selftests: Re-enable hyperv_evmcs/hyperv_svm_test on bare metal
      https://github.com/kvm-x86/linux/commit/d8414067cc17

--
https://github.com/kvm-x86/linux/tree/next