The spec can be found in Intel Software Developer Manual or in
Instruction Set Extensions Programming Reference.
Signed-off-by: Luwei Kang <[email protected]>
Signed-off-by: He Chen <[email protected]>
---
Changes in v2:
* add new macros for new AVX512 scattered features
* add a cpuid_count_edx function to processor.h
---
arch/x86/include/asm/processor.h | 9 +++++++++
arch/x86/kvm/cpuid.c | 13 ++++++++++++-
2 files changed, 21 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 984a7bf..e5ad7a74 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -577,6 +577,15 @@ static inline unsigned int cpuid_edx(unsigned int op)
return edx;
}
+static inline unsigned int cpuid_count_edx(unsigned op, unsigned count)
+{
+ unsigned int eax, ebx, ecx, edx;
+
+ cpuid_count(op, count, &eax, &ebx, &ecx, &edx);
+
+ return edx;
+}
+
/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
static __always_inline void rep_nop(void)
{
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index afa7bbb..9990e7a 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -65,6 +65,11 @@ u64 kvm_supported_xcr0(void)
#define F(x) bit(X86_FEATURE_##x)
+/* These are scattered features in cpufeatures.h. */
+#define KVM_CPUID_BIT_AVX512_4VNNIW 2
+#define KVM_CPUID_BIT_AVX512_4FMAPS 3
+#define KF(x) bit(KVM_CPUID_BIT_##x)
+
int kvm_update_cpuid(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
@@ -376,6 +381,10 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 7.0.ecx*/
const u32 kvm_cpuid_7_0_ecx_x86_features = F(PKU) | 0 /*OSPKE*/;
+ /* cpuid 7.0.edx*/
+ const u32 kvm_cpuid_7_0_edx_x86_features =
+ KF(AVX512_4VNNIW) | KF(AVX512_4FMAPS);
+
/* all calls to cpuid_count() should be made on the same cpu */
get_cpu();
@@ -458,12 +467,14 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* PKU is not yet implemented for shadow paging. */
if (!tdp_enabled)
entry->ecx &= ~F(PKU);
+ entry->edx &= kvm_cpuid_7_0_edx_x86_features;
+ entry->edx &= cpuid_count_edx(7, 0);
} else {
entry->ebx = 0;
entry->ecx = 0;
+ entry->edx = 0;
}
entry->eax = 0;
- entry->edx = 0;
break;
}
case 9:
--
2.7.4