From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56959) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SyN6J-0007Q3-Di for qemu-devel@nongnu.org; Mon, 06 Aug 2012 09:12:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SyN6C-0002mA-Df for qemu-devel@nongnu.org; Mon, 06 Aug 2012 09:12:03 -0400 Received: from mail.profihost.ag ([85.158.179.208]:58750) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SyN6C-0002lv-2Z for qemu-devel@nongnu.org; Mon, 06 Aug 2012 09:11:56 -0400 Message-ID: <501FC299.1050408@profihost.ag> Date: Mon, 06 Aug 2012 15:11:53 +0200 From: Stefan Priebe - Profihost AG MIME-Version: 1.0 References: <5017C8A0.60506@profihost.ag> <5017F19E.4070308@redhat.com> <501817C9.6090405@profihost.ag> <5018EC7D.9090702@redhat.com> <5018F5BB.9070500@profihost.ag> <5018F7E6.4020909@redhat.com> <5018F9F6.70307@profihost.ag> <5018FC9B.8040808@redhat.com> <501E4615.7060801@profihost.ag> <501E4AFD.3020806@redhat.com> <501E96BB.5060702@profihost.ag> <501EC2E2.8010802@profihost.ag> <501F8226.9090500@redhat.com> <501F846C.50903@profihost.ag> <501FB4A8.6080609@redhat.com> <501FBAA2.6050205@redhat.com> In-Reply-To: <501FBAA2.6050205@redhat.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] KVM segfaults with 3.5 while installing ubuntu 12.04 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Avi Kivity Cc: Kevin Wolf , Stefan Hajnoczi , kvm@vger.kernel.org, mtosatti@redhat.com, qemu-devel , linux-kernel can confirm - this fixed it! Am 06.08.2012 14:37, schrieb Avi Kivity: > On 08/06/2012 03:12 PM, Avi Kivity wrote: >> On 08/06/2012 11:46 AM, Stefan Priebe - Profihost AG wrote: >> >>> But still i got the segfault and core dump - this is my main problem? I >>> mean qemu-kvm master isn't declared as stable. So i don't care about the >>> slowness here. >>> >>> What can we do about the core dump and crash? >> >> Okay, I reproduced it; it seems aio=native is the culprit. You can try >> aio=threads as a workaround. >> >> Copying some relevant people (context: aio=native on qemu-kvm-1.1.1 >> segfaults pretty early during guest install) >> > > The following ought to fix it: > > > From: Avi Kivity > Date: Mon, 6 Aug 2012 15:35:02 +0300 > Subject: [PATCH] virtio-mlk: fix use-after-free while handling scsi commands > > The scsi passthrough handler falls through after completing a > request into the failure path, resulting in a use after free. > > Reprducible by running a guest with aio=native on a block device. > > Reported-by: Stefan Priebe > Signed-off-by: Avi Kivity > > diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c > index f21757e..552b3b6 100644 > --- a/hw/virtio-blk.c > +++ b/hw/virtio-blk.c > @@ -254,6 +254,7 @@ static void virtio_blk_handle_scsi(VirtIOBlockReq *req) > > virtio_blk_req_complete(req, status); > g_free(req); > + return; > #else > abort(); > #endif > >