Add the AMD Automatic IBRS feature bit to those being
propagated to the guest, and enable the guest EFER bit.
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
---
arch/x86/kvm/cpuid.c | 2 +-
arch/x86/kvm/reverse_cpuid.h | 2 ++
arch/x86/kvm/svm/svm.c | 3 +++
arch/x86/kvm/x86.c | 3 +++
4 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index dd0fe79521eb..0ed3ad3e9341 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -732,7 +732,7 @@ void kvm_set_cpu_caps(void)
kvm_cpu_cap_init_scattered(CPUID_8000_0021_EAX,
SF(NO_NESTED_DATA_BP) | SF(LFENCE_RDTSC) | 0 /* SmmPgCfgLock */ |
- SF(NULL_SEL_CLR_BASE) | 0 /* PrefetchCtlMsr */
+ SF(NULL_SEL_CLR_BASE) | SF(AUTOIBRS) | 0 /* PrefetchCtlMsr */
);
if (cpu_feature_enabled(X86_FEATURE_LFENCE_RDTSC))
kvm_cpu_cap_set(X86_FEATURE_LFENCE_RDTSC);
diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h
index 184614e27d5b..0bf02c02bb0a 100644
--- a/arch/x86/kvm/reverse_cpuid.h
+++ b/arch/x86/kvm/reverse_cpuid.h
@@ -30,6 +30,7 @@ enum kvm_only_cpuid_leafs {
#define KVM_X86_FEATURE_NO_NESTED_DATA_BP KVM_X86_FEATURE(CPUID_8000_0021_EAX, 0)
#define KVM_X86_FEATURE_LFENCE_RDTSC KVM_X86_FEATURE(CPUID_8000_0021_EAX, 2)
#define KVM_X86_FEATURE_NULL_SEL_CLR_BASE KVM_X86_FEATURE(CPUID_8000_0021_EAX, 6)
+#define KVM_X86_FEATURE_AUTOIBRS KVM_X86_FEATURE(CPUID_8000_0021_EAX, 8)
struct cpuid_reg {
u32 function;
@@ -89,6 +90,7 @@ static __always_inline u32 __feature_translate(int x86_feature)
case X86_FEATURE_NO_NESTED_DATA_BP: return KVM_X86_FEATURE_NO_NESTED_DATA_BP;
case X86_FEATURE_LFENCE_RDTSC: return KVM_X86_FEATURE_LFENCE_RDTSC;
case X86_FEATURE_NULL_SEL_CLR_BASE: return KVM_X86_FEATURE_NULL_SEL_CLR_BASE;
+ case X86_FEATURE_AUTOIBRS: return KVM_X86_FEATURE_AUTOIBRS;
default: break;
}
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index ce362e88a567..1551a791cff0 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4946,6 +4946,9 @@ static __init int svm_hardware_setup(void)
tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX);
+ if (boot_cpu_has(X86_FEATURE_AUTOIBRS))
+ kvm_enable_efer_bits(EFER_AUTOIBRS);
+
/* Check for pause filtering support */
if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) {
pause_filter_count = 0;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2835bd796639..0697d444c715 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1688,6 +1688,9 @@ static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
static bool __kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
{
+ if (efer & EFER_AUTOIBRS && !guest_cpuid_has(vcpu, X86_FEATURE_AUTOIBRS))
+ return false;
+
if (efer & EFER_FFXSR && !guest_cpuid_has(vcpu, X86_FEATURE_FXSR_OPT))
return false;
--
2.34.1
