From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: [PATCH 3/5] KVM: SVM: Fix tsc offset adjustment when running nested Date: Wed, 16 Sep 2009 15:24:17 +0200 Message-ID: <1253107459-8967-4-git-send-email-joerg.roedel@amd.com> References: <1253107459-8967-1-git-send-email-joerg.roedel@amd.com> Mime-Version: 1.0 Content-Type: text/plain Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Graf , Joerg Roedel To: Avi Kivity Return-path: Received: from va3ehsobe003.messaging.microsoft.com ([216.32.180.13]:22906 "EHLO VA3EHSOBE003.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752493AbZIPNYu (ORCPT ); Wed, 16 Sep 2009 09:24:50 -0400 In-Reply-To: <1253107459-8967-1-git-send-email-joerg.roedel@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: When svm_vcpu_load is called while the vcpu is running in guest mode the tsc adjustment made there is lost on the next emulated #vmexit. This causes the tsc running backwards in the guest. This patch fixes the issue by also adjusting the tsc_offset in the emulated hsave area so that it will not get lost. Signed-off-by: Joerg Roedel --- arch/x86/kvm/svm.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 80f5309..84c2c78 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -767,6 +767,8 @@ static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) rdtscll(tsc_this); delta = vcpu->arch.host_tsc - tsc_this; svm->vmcb->control.tsc_offset += delta; + if (is_nested(svm)) + svm->nested.hsave->control.tsc_offset += delta; vcpu->cpu = cpu; kvm_migrate_timers(vcpu); svm->asid_generation = 0; -- 1.6.3.3