From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Lalancette Subject: Re: [PATCH]: Fix MSR_K7_EVNTSEL{0,3} for SVM Date: Thu, 24 Apr 2008 18:13:15 -0400 Message-ID: <481105FB.1080705@redhat.com> References: <480F7E92.6030709@redhat.com> <48103855.70006@qumranet.com> <4810926E.3070900@redhat.com> <4810A538.1070104@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel To: Avi Kivity Return-path: In-Reply-To: <4810A538.1070104@qumranet.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org Avi Kivity wrote: > Now it uses %rsi instead of %esi, and any junk in the upper bits will > cause the ja to be taken. > > We need to get a reduced testcase to the gcc folks, this is a serious > bug. Any changes in the code to work around this would be fragile. > Avi, I've now filed a bug in the upstream gcc database: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36040 And I came up with a reduced test case, available here: http://people.redhat.com/clalance/rsi-test-case.tar.bz2 If I compile the code in the above and look at the disassembly, it shows the problem; however, I can't reproduce the bug by actually running the code. I suspect the %rsi register is always 0 when we start in this userland code, so I never run into the bogus ja, but I just thought I'd mention it. Chris Lalancette ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone