* [V5 PATCH 1/3] KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries
2023-01-11 0:44 [V5 PATCH 0/3] Execute hypercalls according to host cpu Vishal Annapurve
@ 2023-01-11 0:44 ` Vishal Annapurve
2023-01-11 0:44 ` [V5 PATCH 2/3] KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel) Vishal Annapurve
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Vishal Annapurve @ 2023-01-11 0:44 UTC (permalink / raw)
To: x86, kvm, linux-kernel, linux-kselftest
Cc: pbonzini, shuah, bgardon, seanjc, oupton, peterx, vkuznets,
dmatlack, pgonda, andrew.jones, Vishal Annapurve
Replace is_intel/amd_cpu helpers with this_cpu_* helpers to better
convey the intent of querying vendor of the current cpu.
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
.../selftests/kvm/include/x86_64/processor.h | 25 +++++++++++++++---
.../selftests/kvm/lib/x86_64/processor.c | 26 ++-----------------
.../selftests/kvm/x86_64/fix_hypercall_test.c | 4 +--
.../selftests/kvm/x86_64/mmio_warning_test.c | 2 +-
.../kvm/x86_64/pmu_event_filter_test.c | 4 +--
.../vmx_exception_with_invalid_guest_state.c | 2 +-
6 files changed, 30 insertions(+), 33 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 2a5f47d51388..fdb1af5ca611 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -555,6 +555,28 @@ static inline uint32_t this_cpu_model(void)
return x86_model(this_cpu_fms());
}
+static inline bool this_cpu_vendor_string_is(const char *vendor)
+{
+ const uint32_t *chunk = (const uint32_t *)vendor;
+ uint32_t eax, ebx, ecx, edx;
+
+ cpuid(0, &eax, &ebx, &ecx, &edx);
+ return (ebx == chunk[0] && edx == chunk[1] && ecx == chunk[2]);
+}
+
+static inline bool this_cpu_is_intel(void)
+{
+ return this_cpu_vendor_string_is("GenuineIntel");
+}
+
+/*
+ * Exclude early K5 samples with a vendor string of "AMDisbetter!"
+ */
+static inline bool this_cpu_is_amd(void)
+{
+ return this_cpu_vendor_string_is("AuthenticAMD");
+}
+
static inline uint32_t __this_cpu_has(uint32_t function, uint32_t index,
uint8_t reg, uint8_t lo, uint8_t hi)
{
@@ -691,9 +713,6 @@ static inline void cpu_relax(void)
"hlt\n" \
)
-bool is_intel_cpu(void);
-bool is_amd_cpu(void);
-
struct kvm_x86_state *vcpu_save_state(struct kvm_vcpu *vcpu);
void vcpu_load_state(struct kvm_vcpu *vcpu, struct kvm_x86_state *state);
void kvm_x86_state_cleanup(struct kvm_x86_state *state);
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index acfa1d01e7df..7d1768543b91 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -113,7 +113,7 @@ static void sregs_dump(FILE *stream, struct kvm_sregs *sregs, uint8_t indent)
bool kvm_is_tdp_enabled(void)
{
- if (is_intel_cpu())
+ if (this_cpu_is_intel())
return get_kvm_intel_param_bool("ept");
else
return get_kvm_amd_param_bool("npt");
@@ -1006,28 +1006,6 @@ void kvm_x86_state_cleanup(struct kvm_x86_state *state)
free(state);
}
-static bool cpu_vendor_string_is(const char *vendor)
-{
- const uint32_t *chunk = (const uint32_t *)vendor;
- uint32_t eax, ebx, ecx, edx;
-
- cpuid(0, &eax, &ebx, &ecx, &edx);
- return (ebx == chunk[0] && edx == chunk[1] && ecx == chunk[2]);
-}
-
-bool is_intel_cpu(void)
-{
- return cpu_vendor_string_is("GenuineIntel");
-}
-
-/*
- * Exclude early K5 samples with a vendor string of "AMDisbetter!"
- */
-bool is_amd_cpu(void)
-{
- return cpu_vendor_string_is("AuthenticAMD");
-}
-
void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)
{
if (!kvm_cpu_has_p(X86_PROPERTY_MAX_PHY_ADDR)) {
@@ -1236,7 +1214,7 @@ unsigned long vm_compute_max_gfn(struct kvm_vm *vm)
max_gfn = (1ULL << (vm->pa_bits - vm->page_shift)) - 1;
/* Avoid reserved HyperTransport region on AMD processors. */
- if (!is_amd_cpu())
+ if (!this_cpu_is_amd())
return max_gfn;
/* On parts with <40 physical address bits, the area is fully hidden */
diff --git a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
index 32f7e09ef67c..5489c9836ec8 100644
--- a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
+++ b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
@@ -48,10 +48,10 @@ static void guest_main(void)
const uint8_t *other_hypercall_insn;
uint64_t ret;
- if (is_intel_cpu()) {
+ if (this_cpu_is_intel()) {
native_hypercall_insn = vmx_vmcall;
other_hypercall_insn = svm_vmmcall;
- } else if (is_amd_cpu()) {
+ } else if (this_cpu_is_amd()) {
native_hypercall_insn = svm_vmmcall;
other_hypercall_insn = vmx_vmcall;
} else {
diff --git a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
index fb02581953a3..b0a2a0bae0f3 100644
--- a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
+++ b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
@@ -93,7 +93,7 @@ int main(void)
{
int warnings_before, warnings_after;
- TEST_REQUIRE(is_intel_cpu());
+ TEST_REQUIRE(this_cpu_is_intel());
TEST_REQUIRE(!vm_is_unrestricted_guest(NULL));
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index 2de98fce7edd..c728822461b2 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -363,7 +363,7 @@ static void test_pmu_config_disable(void (*guest_code)(void))
*/
static bool use_intel_pmu(void)
{
- return is_intel_cpu() &&
+ return this_cpu_is_intel() &&
kvm_cpu_property(X86_PROPERTY_PMU_VERSION) &&
kvm_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS) &&
kvm_pmu_has(X86_PMU_FEATURE_BRANCH_INSNS_RETIRED);
@@ -397,7 +397,7 @@ static bool use_amd_pmu(void)
uint32_t family = kvm_cpu_family();
uint32_t model = kvm_cpu_model();
- return is_amd_cpu() &&
+ return this_cpu_is_amd() &&
(is_zen1(family, model) ||
is_zen2(family, model) ||
is_zen3(family, model));
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
index 2641b286b4ed..53e1ef2fc774 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
@@ -111,7 +111,7 @@ int main(int argc, char *argv[])
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
- TEST_REQUIRE(is_intel_cpu());
+ TEST_REQUIRE(this_cpu_is_intel());
TEST_REQUIRE(!vm_is_unrestricted_guest(NULL));
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
--
2.39.0.314.g84b9a713c41-goog
^ permalink raw reply [flat|nested] 5+ messages in thread* [V5 PATCH 2/3] KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel)
2023-01-11 0:44 [V5 PATCH 0/3] Execute hypercalls according to host cpu Vishal Annapurve
2023-01-11 0:44 ` [V5 PATCH 1/3] KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries Vishal Annapurve
@ 2023-01-11 0:44 ` Vishal Annapurve
2023-01-11 0:44 ` [V5 PATCH 3/3] KVM: selftests: x86: Use host's native hypercall instruction in kvm_hypercall() Vishal Annapurve
2023-01-19 21:01 ` [V5 PATCH 0/3] Execute hypercalls according to host cpu Sean Christopherson
3 siblings, 0 replies; 5+ messages in thread
From: Vishal Annapurve @ 2023-01-11 0:44 UTC (permalink / raw)
To: x86, kvm, linux-kernel, linux-kselftest
Cc: pbonzini, shuah, bgardon, seanjc, oupton, peterx, vkuznets,
dmatlack, pgonda, andrew.jones, Vishal Annapurve
Cache the host CPU vendor for userspace and share it with guest code.
All the current callers of this_cpu* actually care about host cpu so
they are updated to check host_cpu_is*.
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
.../selftests/kvm/include/x86_64/processor.h | 3 +++
tools/testing/selftests/kvm/lib/x86_64/processor.c | 14 ++++++++++++--
.../selftests/kvm/x86_64/fix_hypercall_test.c | 4 ++--
.../selftests/kvm/x86_64/mmio_warning_test.c | 2 +-
.../selftests/kvm/x86_64/pmu_event_filter_test.c | 4 ++--
.../vmx_exception_with_invalid_guest_state.c | 2 +-
6 files changed, 21 insertions(+), 8 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index fdb1af5ca611..c7885f72132a 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -19,6 +19,9 @@
#include "../kvm_util.h"
+extern bool host_cpu_is_intel;
+extern bool host_cpu_is_amd;
+
#define NMI_VECTOR 0x02
#define X86_EFLAGS_FIXED (1u << 1)
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 7d1768543b91..84915bc7d689 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -19,6 +19,8 @@
#define MAX_NR_CPUID_ENTRIES 100
vm_vaddr_t exception_handlers;
+bool host_cpu_is_amd;
+bool host_cpu_is_intel;
static void regs_dump(FILE *stream, struct kvm_regs *regs, uint8_t indent)
{
@@ -113,7 +115,7 @@ static void sregs_dump(FILE *stream, struct kvm_sregs *sregs, uint8_t indent)
bool kvm_is_tdp_enabled(void)
{
- if (this_cpu_is_intel())
+ if (host_cpu_is_intel)
return get_kvm_intel_param_bool("ept");
else
return get_kvm_amd_param_bool("npt");
@@ -555,6 +557,8 @@ static void vcpu_setup(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
void kvm_arch_vm_post_create(struct kvm_vm *vm)
{
vm_create_irqchip(vm);
+ sync_global_to_guest(vm, host_cpu_is_intel);
+ sync_global_to_guest(vm, host_cpu_is_amd);
}
struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
@@ -1214,7 +1218,7 @@ unsigned long vm_compute_max_gfn(struct kvm_vm *vm)
max_gfn = (1ULL << (vm->pa_bits - vm->page_shift)) - 1;
/* Avoid reserved HyperTransport region on AMD processors. */
- if (!this_cpu_is_amd())
+ if (!host_cpu_is_amd)
return max_gfn;
/* On parts with <40 physical address bits, the area is fully hidden */
@@ -1254,3 +1258,9 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm)
return get_kvm_intel_param_bool("unrestricted_guest");
}
+
+void kvm_selftest_arch_init(void)
+{
+ host_cpu_is_intel = this_cpu_is_intel();
+ host_cpu_is_amd = this_cpu_is_amd();
+}
diff --git a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
index 5489c9836ec8..0f728f05ea82 100644
--- a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
+++ b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c
@@ -48,10 +48,10 @@ static void guest_main(void)
const uint8_t *other_hypercall_insn;
uint64_t ret;
- if (this_cpu_is_intel()) {
+ if (host_cpu_is_intel) {
native_hypercall_insn = vmx_vmcall;
other_hypercall_insn = svm_vmmcall;
- } else if (this_cpu_is_amd()) {
+ } else if (host_cpu_is_amd) {
native_hypercall_insn = svm_vmmcall;
other_hypercall_insn = vmx_vmcall;
} else {
diff --git a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
index b0a2a0bae0f3..ce1ccc4c1503 100644
--- a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
+++ b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
@@ -93,7 +93,7 @@ int main(void)
{
int warnings_before, warnings_after;
- TEST_REQUIRE(this_cpu_is_intel());
+ TEST_REQUIRE(host_cpu_is_intel);
TEST_REQUIRE(!vm_is_unrestricted_guest(NULL));
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index c728822461b2..4dbb454e1760 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -363,7 +363,7 @@ static void test_pmu_config_disable(void (*guest_code)(void))
*/
static bool use_intel_pmu(void)
{
- return this_cpu_is_intel() &&
+ return host_cpu_is_intel &&
kvm_cpu_property(X86_PROPERTY_PMU_VERSION) &&
kvm_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS) &&
kvm_pmu_has(X86_PMU_FEATURE_BRANCH_INSNS_RETIRED);
@@ -397,7 +397,7 @@ static bool use_amd_pmu(void)
uint32_t family = kvm_cpu_family();
uint32_t model = kvm_cpu_model();
- return this_cpu_is_amd() &&
+ return host_cpu_is_amd &&
(is_zen1(family, model) ||
is_zen2(family, model) ||
is_zen3(family, model));
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
index 53e1ef2fc774..ccdfa5dc1a4d 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
@@ -111,7 +111,7 @@ int main(int argc, char *argv[])
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
- TEST_REQUIRE(this_cpu_is_intel());
+ TEST_REQUIRE(host_cpu_is_intel);
TEST_REQUIRE(!vm_is_unrestricted_guest(NULL));
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
--
2.39.0.314.g84b9a713c41-goog
^ permalink raw reply [flat|nested] 5+ messages in thread* [V5 PATCH 3/3] KVM: selftests: x86: Use host's native hypercall instruction in kvm_hypercall()
2023-01-11 0:44 [V5 PATCH 0/3] Execute hypercalls according to host cpu Vishal Annapurve
2023-01-11 0:44 ` [V5 PATCH 1/3] KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries Vishal Annapurve
2023-01-11 0:44 ` [V5 PATCH 2/3] KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel) Vishal Annapurve
@ 2023-01-11 0:44 ` Vishal Annapurve
2023-01-19 21:01 ` [V5 PATCH 0/3] Execute hypercalls according to host cpu Sean Christopherson
3 siblings, 0 replies; 5+ messages in thread
From: Vishal Annapurve @ 2023-01-11 0:44 UTC (permalink / raw)
To: x86, kvm, linux-kernel, linux-kselftest
Cc: pbonzini, shuah, bgardon, seanjc, oupton, peterx, vkuznets,
dmatlack, pgonda, andrew.jones, Vishal Annapurve
Use the host CPU's native hypercall instruction, i.e. VMCALL vs. VMMCALL,
in kvm_hypercall(), as relying on KVM to patch in the native hypercall on
a #UD for the "wrong" hypercall requires KVM_X86_QUIRK_FIX_HYPERCALL_INSN
to be enabled and flat out doesn't work if guest memory is encrypted with
a private key, e.g. for SEV VMs.
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
tools/testing/selftests/kvm/lib/x86_64/processor.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 84915bc7d689..ae1e573d94ce 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -1144,9 +1144,15 @@ uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
{
uint64_t r;
- asm volatile("vmcall"
+ asm volatile("test %[use_vmmcall], %[use_vmmcall]\n\t"
+ "jnz 1f\n\t"
+ "vmcall\n\t"
+ "jmp 2f\n\t"
+ "1: vmmcall\n\t"
+ "2:"
: "=a"(r)
- : "a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3));
+ : "a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3),
+ [use_vmmcall] "r" (host_cpu_is_amd));
return r;
}
--
2.39.0.314.g84b9a713c41-goog
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [V5 PATCH 0/3] Execute hypercalls according to host cpu
2023-01-11 0:44 [V5 PATCH 0/3] Execute hypercalls according to host cpu Vishal Annapurve
` (2 preceding siblings ...)
2023-01-11 0:44 ` [V5 PATCH 3/3] KVM: selftests: x86: Use host's native hypercall instruction in kvm_hypercall() Vishal Annapurve
@ 2023-01-19 21:01 ` Sean Christopherson
3 siblings, 0 replies; 5+ messages in thread
From: Sean Christopherson @ 2023-01-19 21:01 UTC (permalink / raw)
To: Sean Christopherson, x86, kvm, linux-kernel, linux-kselftest,
Vishal Annapurve
Cc: pbonzini, shuah, bgardon, peterx, vkuznets, dmatlack, pgonda,
andrew.jones, Oliver Upton
On Wed, 11 Jan 2023 00:44:42 +0000, Vishal Annapurve wrote:
> Confidential VMs(CVMs) need to execute hypercall instruction as per the CPU
> type. Normally KVM emulates the vmcall/vmmcall instruction by patching
> the guest code at runtime. Such a guest memory manipulation by KVM is
> not allowed with CVMs and is also undesirable in general.
>
> This series adds support of executing hypercall as per the host cpu vendor.
> CPU vendor is queried early during selftest setup and guest setup to be
> reused later.
>
> [...]
Applied to kvm-x86 selftests, thanks!
[1/3] KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries
https://github.com/kvm-x86/linux/commit/093db78b8e6b
[2/3] KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel)
https://github.com/kvm-x86/linux/commit/832ffb370183
[3/3] KVM: selftests: x86: Use host's native hypercall instruction in kvm_hypercall()
https://github.com/kvm-x86/linux/commit/019dfeb31650
--
https://github.com/kvm-x86/linux/tree/next
https://github.com/kvm-x86/linux/tree/fixes
^ permalink raw reply [flat|nested] 5+ messages in thread