From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bandan Das Subject: Re: [PATCH 0/3] Nested TSC handling Date: Tue, 2 Aug 2011 15:24:29 -0400 Message-ID: <20110802192429.GD19569@stratus.com> References: <1312289591-nyh@il.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org, "Roedel, Joerg" , Zachary Amsden , Bandan Das , Marcelo Tosatti , avi@redhat.com, jan.kiszka@web.de, matt.mcgill@gmail.com To: "Nadav Har'El" Return-path: Received: from mailhub4.stratus.com ([134.111.1.17]:34786 "EHLO mailhub4.stratus.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754286Ab1HBTYo (ORCPT ); Tue, 2 Aug 2011 15:24:44 -0400 Content-Disposition: inline In-Reply-To: <1312289591-nyh@il.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 0, Nadav Har'El wrote: > The following are patches I propose for fixing the bug discovered by Bandan > Das and discussed in the "Nested VMX - L1 hangs on running L2" thread. > > The first patch should fix the originally-reported bug, as explained in the > aforementioned thread: A new x86_op read_l1_tsc() is called L1's TSC is > needed, instead of assuming that calling kvm_read_msr() will do that > (because this has to return L2's TSC when a nested guest is running). > > The second and third patches fix relatively-unimportant corner cases in > nested VMX and nested SVM TSC handling. > > I'd appreciate it if the people who noticed this bug can verify that these > patches indeed solve it for them. I can verify that these patches work for me. Thanks Nadav and others for looking into this! I have cc'ed Jan and Matt in case they would be interested in trying out these patches. > Patch statistics: > ----------------- > > arch/x86/include/asm/kvm_host.h | 2 + > arch/x86/kvm/svm.c | 13 ++++++-- > arch/x86/kvm/vmx.c | 48 +++++++++++++++++++++++------- > arch/x86/kvm/x86.c | 8 ++--- > 4 files changed, 54 insertions(+), 17 deletions(-) > > -- > Nadav Har'El > IBM Haifa Research Lab