From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53575) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bi6PC-0005oa-Gt for qemu-devel@nongnu.org; Thu, 08 Sep 2016 16:58:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bi6P8-0006AY-GT for qemu-devel@nongnu.org; Thu, 08 Sep 2016 16:58:42 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:45986) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bi6P8-0006A1-6r for qemu-devel@nongnu.org; Thu, 08 Sep 2016 16:58:38 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u88KvT1D097715 for ; Thu, 8 Sep 2016 16:58:37 -0400 Received: from e31.co.us.ibm.com (e31.co.us.ibm.com [32.97.110.149]) by mx0a-001b2d01.pphosted.com with ESMTP id 25bc2r1jhg-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 08 Sep 2016 16:58:36 -0400 Received: from localhost by e31.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 8 Sep 2016 14:58:36 -0600 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Michael Roth In-Reply-To: <20160905175435.GF24387@stefanha-x1.localdomain> References: <20160817193046.7220.688@loki> <8e3ac487-a3ee-1aef-2240-4c388e0004f7@kamp.de> <20160825172345.17599.42638@loki> <38b365e3-4182-d9d9-28d6-275dfad0da8a@kamp.de> <20160905175435.GF24387@stefanha-x1.localdomain> Date: Thu, 08 Sep 2016 15:58:26 -0500 Message-Id: <20160908205826.17599.75522@loki> Subject: Re: [Qemu-devel] [Qemu-stable] [ANNOUNCE] QEMU 2.6.1 Stable released List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi , Peter Lieven Cc: qemu-devel@nongnu.org, qemu-stable@nongnu.org, Stefan Hajnoczi Quoting Stefan Hajnoczi (2016-09-05 12:54:35) > On Fri, Aug 26, 2016 at 01:45:56PM +0200, Peter Lieven wrote: > > Am 25.08.2016 um 19:23 schrieb Michael Roth: > > > Quoting Peter Lieven (2016-08-25 01:38:13) > > > > 7c509d1 virtio: decrement vq->inuse in virtqueue_discard() > > > > 700f26b virtio: recalculate vq->inuse after migration > > > Looks like these got posted during the freeze :( > > > = > > > > The virtio thing is important because live migration is broken with= out > > > > the fix as 86cc089 is in 2.6.1. > > > Not sure I understand the relation to 86cc089. Wouldn't the check > > > introduced there always pass due to target initializing inuse to 0? > > > = > > > Or is the issue that the fix introduced in 86cc089 is only partially > > > effective due to inuse not being recalculated properly on target? Tha= t might > > > warrant a 2.6.1.1... > > = > > This is what Stefan wrote in the cover letter to the series: > > = > > "I should mention this is for QEMU 2.7. These fixes are needed if the > > CVE-2016-5403 patch has been applied. Without these patches any device = that holds VirtQueueElements acros > > live migration will terminate with a "Virtqueue size exceeded" error me= ssage. virtio-balloon and virtio-scsi are affected. virtio-bl > > probably too but I haven't tested it." > > = > > Maybe > = > The virtio inuse fixes are needed for stable (v2.6.2?) so that the > spurious "Virtqueue size exceeded" on migration is solved. > = > The error can be reproduced when there is a VirtQueueElement pending > across migration (e.g. virtio-blk s->rq failed request list). Thanks for clarifying. I'm planning to do a 2.6.2 to capture these, the patches Peter mentioned, and some other fixes that came during 2.7 RC phase. I have an initial staging tree at: https://github.com/mdroth/qemu/commits/stable-2.6-staging There's still a few PULLs in flight with patches I plan to pull in, but hoping to send out the patch round-up early next week and a release the following week. > = > Stefan