From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: [PATCH 20/58] KVM: VMX: Only reload guest msrs if they are already loaded Date: Sun, 17 Jun 2007 12:44:01 +0300 Message-ID: <11820734801415-git-send-email-avi@qumranet.com> References: <1182073479890-git-send-email-avi@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Return-path: In-Reply-To: <1182073479890-git-send-email-avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org 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 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 096cb6a..b353eaa 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: -- 1.5.0.6 ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/