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 without > > > > 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? That > > > 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 > > message. 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
