From bc6134942dbbf31c25e9bd7c876be5da81c9e1ce Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Thu, 18 Sep 2014 18:24:57 -0300 Subject: [PATCH] KVM: nested VMX: disable perf cpuid reporting Initilization of L2 guest with -cpu host, on L1 guest with -cpu host triggers: (qemu) KVM: entry failed, hardware error 0x7 ... nested_vmx_run: VMCS MSR_{LOAD,STORE} unsupported Nested VMX MSR load/store support is not sufficient to allow perf for L2 guest. Until properly fixed, trap CPUID and disable function 0xA. Signed-off-by: Marcelo Tosatti Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 6 ++++++ arch/x86/kvm/vmx.c | 2 ++ 2 files changed, 8 insertions(+) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index e28d798..976e3a5 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -774,6 +774,12 @@ void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) if (!best) best = check_cpuid_limit(vcpu, function, index); + /* + * Perfmon not yet supported for L2 guest. + */ + if (is_guest_mode(vcpu) && function == 0xa) + best = NULL; + if (best) { *eax = best->eax; *ebx = best->ebx; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e8f08e9..2ab5047 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6986,6 +6986,8 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu) case EXIT_REASON_TASK_SWITCH: return 1; case EXIT_REASON_CPUID: + if (kvm_register_read(vcpu, VCPU_REGS_RAX) == 0xa) + return 0; return 1; case EXIT_REASON_HLT: return nested_cpu_has(vmcs12, CPU_BASED_HLT_EXITING); -- 2.7.4