diff options
| -rw-r--r-- | arch/x86/kvm/x86.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0a4e58dddf36..8b4c69330a87 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -220,13 +220,14 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs; | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) +#define XFEATURE_MASK_CET_ALL (XFEATURE_MASK_CET_USER | XFEATURE_MASK_CET_KERNEL) /* * Note, KVM supports exposing PT to the guest, but does not support context * switching PT via XSTATE (KVM's PT virtualization relies on perf; swapping * PT via guest XSTATE would clobber perf state), i.e. KVM doesn't support * IA32_XSS[bit 8] (guests can/must use RDMSR/WRMSR to save/restore PT MSRs). */ -#define KVM_SUPPORTED_XSS 0 +#define KVM_SUPPORTED_XSS (XFEATURE_MASK_CET_ALL) bool __read_mostly allow_smaller_maxphyaddr = 0; EXPORT_SYMBOL_GPL(allow_smaller_maxphyaddr); @@ -10104,6 +10105,16 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES)) kvm_caps.supported_xss = 0; + if (!kvm_cpu_cap_has(X86_FEATURE_SHSTK) && + !kvm_cpu_cap_has(X86_FEATURE_IBT)) + kvm_caps.supported_xss &= ~XFEATURE_MASK_CET_ALL; + + if ((kvm_caps.supported_xss & XFEATURE_MASK_CET_ALL) != XFEATURE_MASK_CET_ALL) { + kvm_cpu_cap_clear(X86_FEATURE_SHSTK); + kvm_cpu_cap_clear(X86_FEATURE_IBT); + kvm_caps.supported_xss &= ~XFEATURE_MASK_CET_ALL; + } + if (kvm_caps.has_tsc_control) { /* * Make sure the user can only configure tsc_khz values that @@ -12772,10 +12783,11 @@ static void kvm_xstate_reset(struct kvm_vcpu *vcpu, bool init_event) /* * On INIT, only select XSTATE components are zeroed, most components * are unchanged. Currently, the only components that are zeroed and - * supported by KVM are MPX related. + * supported by KVM are MPX and CET related. */ xfeatures_mask = (kvm_caps.supported_xcr0 | kvm_caps.supported_xss) & - (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); + (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR | + XFEATURE_MASK_CET_ALL); if (!xfeatures_mask) return; |