From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1N3E6d-000276-Rp for qemu-devel@nongnu.org; Wed, 28 Oct 2009 15:22:51 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1N3E6Y-00022Q-Vg for qemu-devel@nongnu.org; Wed, 28 Oct 2009 15:22:51 -0400 Received: from [199.232.76.173] (port=51104 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1N3E6Y-00022K-QU for qemu-devel@nongnu.org; Wed, 28 Oct 2009 15:22:46 -0400 Received: from mail-bw0-f212.google.com ([209.85.218.212]:46213) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1N3E6Y-0004hM-JP for qemu-devel@nongnu.org; Wed, 28 Oct 2009 15:22:46 -0400 Received: by bwz4 with SMTP id 4so1668619bwz.2 for ; Wed, 28 Oct 2009 12:22:44 -0700 (PDT) MIME-Version: 1.0 Sender: dustin.kirkland@gmail.com Date: Wed, 28 Oct 2009 14:22:43 -0500 Message-ID: From: Dustin Kirkland Content-Type: text/plain; charset=ISO-8859-1 Subject: [Qemu-devel] qemu-kvm-0.11 regression, crashes on older guests with virtio network List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, kvm@vger.kernel.org, Anthony Liguori I believe that we have identified a regression in qemu-kvm-0.11.0. The kvm process crashes for older guests with virtio networking, when the guest's incoming network connection is saturated. The subject guest is Ubuntu 8.04 Hardy, 2.6.24 kernel with virtio backports. For your convenience, I have uploaded a stock, ~260MB Ubuntu 8.04 disk image (user/pw = ubuntu) that I'm using to reproduce the problem at: * http://rookery.canonical.com/~kirkland/hardy.img.bz2 The command line is: * sudo /usr/bin/kvm -m 512 -net nic,model=virtio -net tap,script=/home/kirkland/bin/bridge.sh -drive file=hardy.img,if=virtio,index=0,boot=on The bridge script is: * http://rookery.canonical.com/~kirkland/bridge.sh I'm saturating the guest's incoming network connection, with: user@guest$ nc -lp 1234 > /dev/null and user@host$ cat /dev/urandom | nc -w 3 guest_ip 1234 In less than a second of sending, the vm crashes with: virtio-net truncating packet I have strace logs, if that's helpful. I have not reproduced the problem: a) by saturating the guest's outgoing network b) with newer guests ( >= 2.6.27 ) c) on kvm-84 on the host We're tracking this issue at: * https://bugs.launchpad.net/ubuntu/+source/qemu-kvm/+bug/458521 I'll gladly review and test patches, or take pointers on where I might look to solve this issue. -- :-Dustin