From e9737468829c2f6abc0c67e5372f8878dff11653 Mon Sep 17 00:00:00 2001 From: Like Xu Date: Mon, 17 Jan 2022 15:45:31 +0800 Subject: KVM: x86/cpuid: Clear XFD for component i if the base feature is missing According to Intel extended feature disable (XFD) spec, the sub-function i (i > 1) of CPUID function 0DH enumerates "details for state component i. ECX[2] enumerates support for XFD support for this state component." If KVM does not report F(XFD) feature (e.g. due to CONFIG_X86_64), then the corresponding XFD support for any state component i should also be removed. Translate this dependency into KVM terms. Fixes: 690a757d610e ("kvm: x86: Add CPUID support for Intel AMX") Signed-off-by: Like Xu Message-Id: <20220117074531.76925-1-likexu@tencent.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index a7c280d2113b..3902c28fb6cb 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -936,6 +936,9 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) --array->nent; continue; } + + if (!kvm_cpu_cap_has(X86_FEATURE_XFD)) + entry->ecx &= ~BIT_ULL(2); entry->edx = 0; } break; -- cgit v1.2.3