From eff708bc2bacd4f22cf844871341bef341bd096a Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sun, 6 May 2007 16:10:01 +0300 Subject: [PATCH] KVM: VMX: Only reload guest msrs if they are already loaded If we set an msr via an ioctl() instead of by handling a guest exit, we have the host state loaded, so reloading the msrs would clobber host state instead of guest state. This fixes a host oops (and loss of a cpu) on a guest reboot. Signed-off-by: Avi Kivity --- drivers/kvm/vmx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 096cb6a1e899..b353eaa0a441 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -600,7 +600,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) msr = find_msr_entry(vcpu, msr_index); if (msr) msr->data = data; - load_msrs(vcpu->guest_msrs, NR_BAD_MSRS); + if (vcpu->vmx_host_state.loaded) + load_msrs(vcpu->guest_msrs, NR_BAD_MSRS); break; #endif case MSR_IA32_SYSENTER_CS: -- 2.20.1