On Fri, Feb 22 2013 at 5:47am -0500, Bart Van Assche <bvanassche@xxxxxxx> wrote: > As the comment above rq_completed() explains, md members must > not be touched after the dm_put() at the end of that function > has been invoked. Avoid that the md->queue can be run > asynchronously after the last md reference has been dropped by > running that queue synchronously. This patch fixes the > following kernel oops: > > general protection fault: 0000 [#1] SMP > RIP: 0010:[<ffffffff810fe754>] [<ffffffff810fe754>] mempool_free+0x24/0xb0 > Call Trace: > <IRQ> > [<ffffffff81187417>] bio_put+0x97/0xc0 > [<ffffffffa02247a5>] end_clone_bio+0x35/0x90 [dm_mod] > [<ffffffff81185efd>] bio_endio+0x1d/0x30 > [<ffffffff811f03a3>] req_bio_endio.isra.51+0xa3/0xe0 > [<ffffffff811f2f68>] blk_update_request+0x118/0x520 > [<ffffffff811f3397>] blk_update_bidi_request+0x27/0xa0 > [<ffffffff811f343c>] blk_end_bidi_request+0x2c/0x80 > [<ffffffff811f34d0>] blk_end_request+0x10/0x20 > [<ffffffffa000b32b>] scsi_io_completion+0xfb/0x6c0 [scsi_mod] > [<ffffffffa000107d>] scsi_finish_command+0xbd/0x120 [scsi_mod] > [<ffffffffa000b12f>] scsi_softirq_done+0x13f/0x160 [scsi_mod] > [<ffffffff811f9fd0>] blk_done_softirq+0x80/0xa0 > [<ffffffff81044551>] __do_softirq+0xf1/0x250 > [<ffffffff8142ee8c>] call_softirq+0x1c/0x30 > [<ffffffff8100420d>] do_softirq+0x8d/0xc0 > [<ffffffff81044885>] irq_exit+0xd5/0xe0 > [<ffffffff8142f3e3>] do_IRQ+0x63/0xe0 > [<ffffffff814257af>] common_interrupt+0x6f/0x6f > <EOI> > [<ffffffffa021737c>] srp_queuecommand+0x8c/0xcb0 [ib_srp] > [<ffffffffa0002f18>] scsi_dispatch_cmd+0x148/0x310 [scsi_mod] > [<ffffffffa000a38e>] scsi_request_fn+0x31e/0x520 [scsi_mod] > [<ffffffff811f1e57>] __blk_run_queue+0x37/0x50 > [<ffffffff811f1f69>] blk_delay_work+0x29/0x40 > [<ffffffff81059003>] process_one_work+0x1c3/0x5c0 > [<ffffffff8105b22e>] worker_thread+0x15e/0x440 > [<ffffffff8106164b>] kthread+0xdb/0xe0 > [<ffffffff8142db9c>] ret_from_fork+0x7c/0xb0 Your commit header should probably reference commit a8c32a5c98943d370ea606a2e7dc04717eb92206 ("dm: fix deadlock with request based dm and queue request_fn recursion") and cc: stable with "v3.7+" guidance. Acked-by: Mike Snitzer <snitzer@xxxxxxxxxx> -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel