On Tue, Jan 13 2015 at 7:29am -0500, Bart Van Assche <bart.vanassche@xxxxxxxxxxx> wrote: > On 01/12/15 21:22, Mike Snitzer wrote: > > FYI, I staged Keith's patch here: > > https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-for-3.20-blk-mq&id=7004ddf2462df38c6e3232ac020ed6ff655cc07e > > > > Bart, this is the tip of the linux-dm.git "dm-for-3.20-blk-mq" branch. > > Please test, it should hopefully take care of the stall you've been > > seeing. > > Hello Mike, > > In the quick test I ran the I/O stalls were indeed gone. Thanks :-) Good news, followed by a new mole rearing its head ;) > However, I hit another issue while running I/O on top of a multipath > device (on a kernel with lockdep and SLUB memory poisoning enabled): > > NMI watchdog: BUG: soft lockup - CPU#7 stuck for 23s! [kdmwork-253:0:3116] > CPU: 7 PID: 3116 Comm: kdmwork-253:0 Tainted: G W 3.19.0-rc4-debug+ #1 > Call Trace: > [<ffffffff8118e4be>] kmem_cache_alloc+0x28e/0x2c0 > [<ffffffff81346aca>] alloc_iova_mem+0x1a/0x20 > [<ffffffff81342c8e>] alloc_iova+0x2e/0x250 > [<ffffffff81344b65>] intel_alloc_iova+0x95/0xd0 > [<ffffffff81348a15>] intel_map_sg+0xc5/0x260 > [<ffffffffa07e0661>] srp_queuecommand+0xa11/0xc30 [ib_srp] > [<ffffffffa001698e>] scsi_dispatch_cmd+0xde/0x5a0 [scsi_mod] > [<ffffffffa0017480>] scsi_queue_rq+0x630/0x700 [scsi_mod] > [<ffffffff8125683d>] __blk_mq_run_hw_queue+0x1dd/0x370 > [<ffffffff81256aae>] blk_mq_alloc_request+0xde/0x150 > [<ffffffff8124bade>] blk_get_request+0x2e/0xe0 > [<ffffffffa07ebd0f>] __multipath_map.isra.15+0x1cf/0x210 [dm_multipath] > [<ffffffffa07ebd6a>] multipath_clone_and_map+0x1a/0x20 [dm_multipath] > [<ffffffffa044abb5>] map_tio_request+0x1d5/0x3a0 [dm_mod] > [<ffffffff81075d16>] kthread_worker_fn+0x86/0x1b0 > [<ffffffff81075c0f>] kthread+0xef/0x110 > [<ffffffff814db42c>] ret_from_fork+0x7c/0xb0 Unfortunate. Is this still with a 16MB backing device or is it real hardware? Can you share the workload so that myself and/or Keith could try to reproduce? -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
