On Wed, Oct 10, 2018 at 02:28:09PM +0200, Jan Kara wrote: > On Wed 10-10-18 13:42:27, Johannes Thumshirn wrote: > > On Wed, Oct 10, 2018 at 07:19:00PM +0900, Tetsuo Handa wrote: > > > On 2018/10/10 19:04, Jan Kara wrote: > > > > Hi, > > > > > > > > this patch series fixes oops and possible deadlocks as reported by syzbot [1] > > > > [2]. The second patch in the series (from Tetsuo) fixes the oops, the remaining > > > > patches are cleaning up the locking in the loop driver so that we can in the > > > > end reasonably easily switch to rereading partitions without holding mutex > > > > protecting the loop device. > > > > > > > > I have lightly tested the patches by creating, deleting, and modifying loop > > > > devices but if there's some more comprehensive loopback device testsuite, I > > > > can try running it. Review is welcome! > > > > > > Testing on linux-next by syzbot will be the most comprehensive. ;-) > > > > Apart from that blktests has a loop category and I think it could also be > > worthwhile to add the C reproducer from syzkaller to blktests. > > Yeah, I did run loop tests now and they ran fine. I can try converting the > syzbot reproducers into something legible but it will take a while. There is one C repropducer which can be used (it just needs minor modifications to pass in the device instead of loop0). See for instance blktests/src/sg/syzkaller1.c -- Johannes Thumshirn SUSE Labs jthumshirn@xxxxxxx +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
