Set original kvm_caps.supported_xss to (host_xss & KVM_SUPPORTED_XSS) if XSAVES is supported. host_xss contains the host supported xstate feature bits for thread FPU context switch, KVM_SUPPORTED_XSS includes all KVM enabled XSS feature bits, the resulting value represents the supervisor xstates that are available to guest and are backed by host FPU framework for swapping {guest,host} XSAVE-managed registers/MSRs. Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx> Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx> Reviewed-by: Chao Gao <chao.gao@xxxxxxxxx> --- arch/x86/kvm/x86.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b502d68a2576..60b574fc04d1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -226,6 +226,8 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs; | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) +#define KVM_SUPPORTED_XSS 0 + u64 __read_mostly host_efer; EXPORT_SYMBOL_GPL(host_efer); @@ -9737,12 +9739,13 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0; } + if (boot_cpu_has(X86_FEATURE_XSAVES)) { + rdmsrl(MSR_IA32_XSS, host_xss); + kvm_caps.supported_xss = host_xss & KVM_SUPPORTED_XSS; + } rdmsrl_safe(MSR_EFER, &host_efer); - if (boot_cpu_has(X86_FEATURE_XSAVES)) - rdmsrl(MSR_IA32_XSS, host_xss); - kvm_init_pmu_capability(ops->pmu_ops); if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) -- 2.43.0