On Wed, 23 May 2018, Ben Hutchings wrote:
On Mon, 2018-05-21 at 17:54 -0400, Konrad Rzeszutek Wilk wrote:
The X86_FEATURE_SSBD is an synthetic CPU feature - that is it bit location has no relevance to the real CPUID 0x7.EBX[31] bit position. For that we need the new CPU feature name.
Fixes: 52817587e706 ("x86/cpufeatures: Disentangle SSBD enumeration")
CC: Paolo Bonzini pbonzini@redhat.com Cc: "Radim Krčmář" rkrcmar@redhat.com Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: "H. Peter Anvin" hpa@zytor.com Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com
arch/x86/kvm/cpuid.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index ced851169730..598461e24be3 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -407,8 +407,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 7.0.edx*/ const u32 kvm_cpuid_7_0_edx_x86_features =
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | F(SSBD) |F(ARCH_CAPABILITIES);
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES);/* all calls to cpuid_count() should be made on the same cpu */ get_cpu();
For 4.9-stable, guest_cpuid_has_spec_ctrl() needs a similar fix.
Ben.
Do you mean something like this?
--- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -179,7 +179,7 @@ static inline bool guest_cpuid_has_spec_ctrl(struct kvm_vcpu *vcpu) if (best && (best->ebx & bit(X86_FEATURE_AMD_IBRS))) return true; best = kvm_find_cpuid_entry(vcpu, 7, 0); - return best && (best->edx & (bit(X86_FEATURE_SPEC_CTRL) | bit(X86_FEATURE_SSBD))); + return best && (best->edx & (bit(X86_FEATURE_SPEC_CTRL) | bit(X86_FEATURE_SPEC_CTRL_SSBD))); }
static inline bool guest_cpuid_has_arch_capabilities(struct kvm_vcpu *vcpu)