From 2a7921b7a033d5cfc176690d6297c82846c582b2 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Sun, 12 Aug 2012 16:12:29 +0300 Subject: [PATCH] KVM: VMX: restore MSR_IA32_DEBUGCTLMSR after VMEXIT MSR_IA32_DEBUGCTLMSR is zeroed on VMEXIT. Restore it to the correct value. Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/vmx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index cc8ad98..d0f4bec 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6222,6 +6222,7 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx) static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); + unsigned long debugctlmsr; if (is_guest_mode(vcpu) && !vmx->nested.nested_run_pending) { struct vmcs12 *vmcs12 = get_vmcs12(vcpu); @@ -6261,6 +6262,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx_set_interrupt_shadow(vcpu, 0); atomic_switch_perf_msrs(vmx); + debugctlmsr = get_debugctlmsr(); vmx->__launched = vmx->loaded_vmcs->launched; asm( @@ -6362,6 +6364,10 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) #endif ); + /* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */ + if (debugctlmsr) + update_debugctlmsr(debugctlmsr); + #ifndef CONFIG_X86_64 /* * The sysexit path does not restore ds/es, so we must set them to -- 2.7.4