From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aravind Gopalakrishnan Subject: Re: [RFC Patch v3 18/18] x86/hvm: Always set pending event injection when loading VMC[BS] state. Date: Wed, 17 Sep 2014 09:29:06 -0500 Message-ID: <54199AB2.4070204@amd.com> References: <1409908261-18682-1-git-send-email-wency@cn.fujitsu.com> <1409908261-18682-19-git-send-email-wency@cn.fujitsu.com> <54106910.1080207@amd.com> <20140911103516.GB31323@deinos.phlegethon.org> <54193EAA.4020801@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <54193EAA.4020801@cn.fujitsu.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Wen Congyang Cc: Yang Hongyang , Ian Campbell , Dong Eddie , Jiang Yunhong , Ian Jackson , Tim Deegan , Jun Nakajima , xen devel , Suravee Suthikulpanit , Lai Jiangshan List-Id: xen-devel@lists.xenproject.org On 9/17/2014 2:56 AM, Wen Congyang wrote: > On 09/11/2014 06:35 PM, Tim Deegan wrote: >> At 10:06 -0500 on 10 Sep (1410340016), Aravind Gopalakrishnan wrote: >>> Hi, >>> You mention that this 'fix' is just copied for svm. But you have not >>> seen the problem of "VM_ENTRY_INTR_INFO may be valid" (whose svm >>> equivalent is "vmcb->eventinj.bytes is valid"). >>> My concern is that we should test colo mode for svm first, since, if the >>> problem is never really seen on svm, then fix may not be _necessary_ >> I think it's obvious by inspection of the code (and indeed the patch) >> that SVM has the equivalent bug. >> >>> At this point, my problems are with test setups. I can help testing >>> scenarios, but as Wen had mentioned, 'colo testing' might be the way to >>> test. >>> So, if I can get some pointers to how I can reproduce the issue at hand, >>> then it would be very helpful. >>> >>> (Tim had mentioned we could try to simulate it by running a guest that >>> takes lot of faults and save-restore another guest over it. However, >>> I am not having much luck following this route. I got a hvm guest to >>> continuously take SW exceptions on all vcpus and tried to save-restore. >>> I can't see vmcb->eventinj.bytes containing any valid info.) >> Although I think that getting COLO running on SVM is a gret idea, it >> shouldn't block acceptance of this fix. I've attached a program >> that tests for the bug. Run it against any HVM guest (and then >> destroy the guest because the test will have corrupted its state). > Hi, Aravind Gopalakrishnan > > Do you have time to test this patch with the test program? > Wen, Apologize for the delay, but couple of other stuff has pre-empted this. I'll try the test today and let you know. - Aravind.