From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Clayton Subject: Fwd: Re: kvm-31 seg fault Date: Tue, 24 Jul 2007 22:02:05 +0000 Message-ID: <200707242202.05192.chris2553@googlemail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Forgot to cc this to the list, sorry ---------- Forwarded Message ---------- Subject: Re: [kvm-devel] kvm-31 seg fault Date: Tuesday 24 July 2007 From: Chris Clayton To: Avi Kivity Hi again Avi, On Sunday 22 July 2007, you wrote: > Chris Clayton wrote: > > On Sunday 22 July 2007, you wrote: > >> Chris Clayton wrote: > >>> Hi, > >>> > >>> I'm getting a seg fault running kvm-31 on linux-2.6.22.1-cfs-v19 and > >>> linux-2.6.22-git17. > >>> > >>> If I use the kvm-31 kernel modules with qemu from kvm-29, all is OK > >>> Also, running "non-kvm" guests, such as Windows ME, works fine with > >>> kvm-31. > >>> > >>> I have an strace log but its over 99 Kilobytes, so I haven't attached > >>> it to this mail. More than happy to compress it and send it by private > >>> mail, if required. > >>> > >>> I'm not subscribed, so please cc me. > >> > >> Please send it to me. What guest are you running? Is the host 32-bit > >> or 64-bit? > > > > Attached is the log from 2.6.22-git17 > > > > The host is 32bit and the guest is freebsd-6.2 although I get the same > > seg fault with slackware 10.2 and damn small linux 3.1 (all 32 bit). > > Unfortunately that doesn't help. Can you generate a core ('ulimit -c > unlimited' may help) and get a stacktrace from gdb? I've been doing some more digging around here and thought I'd report my findings. I've found that under kvm 31 and 33, qemu-system-x86_64 always fails with a seg fault when the (__thread) variable vcpu_env (declared at line 33 of qemu-kvm.c) is accessed in kvm_update_interrupt_request(). I've inserted useless statements (printf()s and assignments) at the head of the function, and always get the seg fault at the first access to the variable. I'm building qemu with gcc-3.4.6, but to eliminate a fault in that compiler, I've also built the application on my laptop with gcc-3.3.6 and copied the binary over to my desktop machine. I still get the seg fault. Sorry if this is just noise on your line, but I thought I'd send it just in case it's useful. Chris ------------------------------------------------------- ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/