From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932322AbaFSLRe (ORCPT ); Thu, 19 Jun 2014 07:17:34 -0400 Received: from mail-pa0-f44.google.com ([209.85.220.44]:61899 "EHLO mail-pa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757613AbaFSLRd (ORCPT ); Thu, 19 Jun 2014 07:17:33 -0400 Message-ID: <53A2C6B0.3090200@gmail.com> Date: Thu, 19 Jun 2014 19:17:04 +0800 From: =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?= User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: gleb@kernel.org, pbonzini@redhat.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com CC: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kvm: fix hyperv tsc page clear wrong address References: <53A2BB7B.8070507@gmail.com> <53A2BC1A.4050702@gmail.com> In-Reply-To: <53A2BC1A.4050702@gmail.com> Content-Type: multipart/mixed; boundary="------------010904010501080300020809" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------010904010501080300020809 Content-Type: text/plain; charset=gb18030 Content-Transfer-Encoding: 7bit This is more concisely >>From 6ddeb18347f9dda0fe37702e0d067a4129a89b54 Mon Sep 17 00:00:00 2001 From: Xiaoming Gao Date: Thu, 19 Jun 2014 19:14:57 +0800 Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead guest to get wrong clocksource. windows guest will get strong impact, QueryPerformanceCounter will always return 0 ,all things in windows rely on clock source, will in serious chaos. Signed-off-by: Xiaoming Gao --- arch/x86/kvm/x86.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f32a025..f644933 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1898,7 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data) if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE)) break; gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT; - if (kvm_write_guest(kvm, data, + if (kvm_write_guest(kvm, gfn << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT, &tsc_ref, sizeof(tsc_ref))) return 1; mark_page_dirty(kvm, gfn); -- 1.7.1 --------------010904010501080300020809 Content-Type: text/plain; charset=gb18030; name="0001-kvm-fix-hyperv-tsc-page-clear-wrong-address.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0001-kvm-fix-hyperv-tsc-page-clear-wrong-address.patch" >>From 6ddeb18347f9dda0fe37702e0d067a4129a89b54 Mon Sep 17 00:00:00 2001 From: Xiaoming Gao Date: Thu, 19 Jun 2014 19:14:57 +0800 Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead guest to get wrong clocksource. windows guest will get strong impact, QueryPerformanceCounter will always return 0 ,all things in windows rely on clock source, will in serious chaos. Signed-off-by: Xiaoming Gao --- arch/x86/kvm/x86.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f32a025..f644933 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1898,7 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data) if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE)) break; gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT; - if (kvm_write_guest(kvm, data, + if (kvm_write_guest(kvm, gfn << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT, &tsc_ref, sizeof(tsc_ref))) return 1; mark_page_dirty(kvm, gfn); -- 1.7.1 --------------010904010501080300020809--