From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: [PATCH 4/5] KVM: SVM: Handle tsc in svm_get_msr/svm_set_msr correctly Date: Wed, 16 Sep 2009 15:24:18 +0200 Message-ID: <1253107459-8967-5-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: In-Reply-To: <1253107459-8967-1-git-send-email-joerg.roedel@amd.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org When running nested we need to touch the l1 guests tsc_offset. Otherwise changes will be lost or a wrong value be read. Signed-off-by: Joerg Roedel --- arch/x86/kvm/svm.c | 23 +++++++++++++++++------ 1 files changed, 17 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 84c2c78..e193cf9 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2059,10 +2059,14 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 *data) switch (ecx) { case MSR_IA32_TSC: { - u64 tsc; + u64 tsc_offset; - rdtscll(tsc); - *data = svm->vmcb->control.tsc_offset + tsc; + if (is_nested(svm)) + tsc_offset = svm->nested.hsave->control.tsc_offset; + else + tsc_offset = svm->vmcb->control.tsc_offset; + + *data = tsc_offset + native_read_tsc(); break; } case MSR_K6_STAR: @@ -2148,10 +2152,17 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data) switch (ecx) { case MSR_IA32_TSC: { - u64 tsc; + u64 tsc_offset = data - native_read_tsc(); + u64 g_tsc_offset = 0; + + if (is_nested(svm)) { + g_tsc_offset = svm->vmcb->control.tsc_offset - + svm->nested.hsave->control.tsc_offset; + svm->nested.hsave->control.tsc_offset = tsc_offset; + } + + svm->vmcb->control.tsc_offset = tsc_offset + g_tsc_offset; - rdtscll(tsc); - svm->vmcb->control.tsc_offset = data - tsc; break; } case MSR_K6_STAR: -- 1.6.3.3