The Intel Virtualization Technology FlexMigration Application Note says, "When CPUID faulting is enabled, all executions of the CPUID instruction outside system-management mode (SMM) cause a general-protection exception (#GP(0)) if the current privilege level (CPL) is greater than 0." Always allow the execution of CPUID in SMM. Fixes: db2336a80489 ("KVM: x86: virtualize cpuid faulting") Signed-off-by: Jim Mattson --- arch/x86/kvm/cpuid.c | 3 ++- arch/x86/kvm/emulate.c | 6 +++--- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 7fe4e58a6ebf..863ce81023e9 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -2157,7 +2157,8 @@ int kvm_emulate_cpuid(struct kvm_vcpu *vcpu) { u32 eax, ebx, ecx, edx; - if (cpuid_fault_enabled(vcpu) && !kvm_require_cpl(vcpu, 0)) + if (!is_smm(vcpu) && cpuid_fault_enabled(vcpu) && + !kvm_require_cpl(vcpu, 0)) return 1; eax = kvm_rax_read(vcpu); diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index c8e292e9a24d..4b7289a82bf8 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3583,10 +3583,10 @@ static int em_cpuid(struct x86_emulate_ctxt *ctxt) u64 msr = 0; ctxt->ops->get_msr(ctxt, MSR_MISC_FEATURES_ENABLES, &msr); - if (msr & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT && - ctxt->ops->cpl(ctxt)) { + if (!ctxt->ops->is_smm(ctxt) && + (msr & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT && + ctxt->ops->cpl(ctxt))) return emulate_gp(ctxt, 0); - } eax = reg_read(ctxt, VCPU_REGS_RAX); ecx = reg_read(ctxt, VCPU_REGS_RCX); -- 2.53.0.239.g8d8fc8a987-goog