On Mon, 11 Jul 2016, Eric Wheeler wrote: > On Tue, 5 Jul 2016, Jackie Tea wrote: > > > I've been using bcache on a Xen host (sitting on an LVM partition) for > > many months without problems > > > > Now that I added DRBD on top of bcache, bcache locks up within a few > > hours, giving me this message: > > This might be related to the thread to this thread: > > https://lkml.org/lkml/2016/6/22/172 > and this patch: > https://patchwork.kernel.org/patch/9223697/ > > Notably, this bug was introduced in 4.3 and newer. You might try 4.1 and > see if your problem resolves itself, or 4.8 is supposed to fix this too if > the patch gets in. Make sure you have these patches, too. Looking at your stack, you definitely want "A", maybe the others as well: A. [PATCH v2] block: make sure big bio is splitted into at most 256 bvecs by Ming Lei: https://patchwork.kernel.org/patch/9169483/ B. block: don't make BLK_DEF_MAX_SECTORS too big by Shaohua Li: http://www.spinics.net/lists/linux-bcache/msg03525.html D. dm-crypt: Fix error with too large bios by Mikulas Patocka: https://patchwork.kernel.org/patch/9138595/ E. block: fix blk_queue_split() resource exhaustion by Lars Ellenberg: https://patchwork.kernel.org/patch/9223697/ (as above, previous post. You probably don't need "D" for your setup by looking at lsblk. [ "C" excluded on purpose because "E" supersedes it, but here it is if you'd like to try. Note that "E" and "C" are mutually exclusive: C. [1/3] block: flush queued bios when process blocks to avoid deadlock by Mikulas Patocka: https://patchwork.kernel.org/patch/9204125/ (was https://patchwork.kernel.org/patch/7398411/) ] Please try and let us know which (if any of these) fix your issue! -Eric -- Eric Wheeler > > > > > > > Jul 5 04:06:43 dom0 kernel: [23043.136864] INFO: task > > bcache_writebac:1342 blocked for more than 120 seconds. > > Jul 5 04:06:43 dom0 kernel: [23043.136896] Not tainted > > 4.4.0-28-generic #47-Ubuntu > > Jul 5 04:06:43 dom0 kernel: [23043.136916] "echo 0 > > > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > > Jul 5 04:06:43 dom0 kernel: [23043.136946] bcache_writebac D > > ffff880000983d18 0 1342 2 0x00000000 > > Jul 5 04:06:43 dom0 kernel: [23043.136952] ffff880000983d18 > > 0000000000007ff0 ffffffff81e11500 ffff880035705780 > > Jul 5 04:06:43 dom0 kernel: [23043.136955] ffff880000984000 > > ffff880005080af0 ffff880005080ad8 ffffffff00000000 > > Jul 5 04:06:43 dom0 kernel: [23043.136958] ffffffff00000003 > > ffff880000983d30 ffffffff818235b5 ffff880035705780 > > Jul 5 04:06:43 dom0 kernel: [23043.136962] Call Trace: > > Jul 5 04:06:43 dom0 kernel: [23043.136971] [<ffffffff818235b5>] > > schedule+0x35/0x80 > > Jul 5 04:06:43 dom0 kernel: [23043.136974] [<ffffffff81826202>] > > rwsem_down_write_failed+0x202/0x350 > > Jul 5 04:06:43 dom0 kernel: [23043.136990] [<ffffffffc015e6d0>] ? > > read_dirty+0x370/0x370 [bcache] > > Jul 5 04:06:43 dom0 kernel: [23043.136995] [<ffffffff813f9643>] > > call_rwsem_down_write_failed+0x13/0x20 > > Jul 5 04:06:43 dom0 kernel: [23043.136999] [<ffffffff81825a3d>] ? > > down_write+0x2d/0x40 > > Jul 5 04:06:43 dom0 kernel: [23043.137009] [<ffffffffc015e72b>] > > bch_writeback_thread+0x5b/0x4c0 [bcache] > > Jul 5 04:06:43 dom0 kernel: [23043.137020] [<ffffffffc015e6d0>] ? > > read_dirty+0x370/0x370 [bcache] > > Jul 5 04:06:43 dom0 kernel: [23043.137024] [<ffffffff810a0808>] > > kthread+0xd8/0xf0 > > Jul 5 04:06:43 dom0 kernel: [23043.137027] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:06:43 dom0 kernel: [23043.137029] [<ffffffff81827a4f>] > > ret_from_fork+0x3f/0x70 > > Jul 5 04:06:43 dom0 kernel: [23043.137032] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:06:43 dom0 kernel: [23043.137043] INFO: task > > blkback.5.hda:3357 blocked for more than 120 seconds. > > Jul 5 04:06:43 dom0 kernel: [23043.137069] Not tainted > > 4.4.0-28-generic #47-Ubuntu > > Jul 5 04:06:43 dom0 kernel: [23043.137090] "echo 0 > > > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > > Jul 5 04:06:43 dom0 kernel: [23043.137119] blkback.5.hda D > > ffff88002341ba48 0 3357 2 0x00000000 > > Jul 5 04:06:43 dom0 kernel: [23043.137122] ffff88002341ba48 > > ffff88002341ba08 ffffffff81e11500 ffff880034189900 > > Jul 5 04:06:43 dom0 kernel: [23043.137124] ffff88002341c000 > > ffff880005080ad8 ffff880005080af0 ffff880023e08e60 > > Jul 5 04:06:43 dom0 kernel: [23043.137126] ffff880005080000 > > ffff88002341ba60 ffffffff818235b5 ffff880034189900 > > Jul 5 04:06:43 dom0 kernel: [23043.137128] Call Trace: > > Jul 5 04:06:43 dom0 kernel: [23043.137131] [<ffffffff818235b5>] > > schedule+0x35/0x80 > > Jul 5 04:06:43 dom0 kernel: [23043.137133] [<ffffffff81826430>] > > rwsem_down_read_failed+0xe0/0x140 > > Jul 5 04:06:43 dom0 kernel: [23043.137136] [<ffffffff811903e5>] ? > > mempool_alloc_slab+0x15/0x20 > > Jul 5 04:06:43 dom0 kernel: [23043.137138] [<ffffffff813f9614>] > > call_rwsem_down_read_failed+0x14/0x30 > > Jul 5 04:06:43 dom0 kernel: [23043.137140] [<ffffffff81825a00>] ? > > down_read+0x20/0x30 > > Jul 5 04:06:43 dom0 kernel: [23043.137148] [<ffffffffc01522a2>] > > cached_dev_make_request+0x682/0xcc0 [bcache] > > Jul 5 04:06:43 dom0 kernel: [23043.137151] [<ffffffff813bba52>] > > generic_make_request+0xf2/0x1d0 > > Jul 5 04:06:43 dom0 kernel: [23043.137153] [<ffffffff813bbba6>] > > submit_bio+0x76/0x170 > > Jul 5 04:06:43 dom0 kernel: [23043.137157] [<ffffffffc04ebbb7>] > > dispatch_rw_block_io+0x7b7/0xab0 [xen_blkback] > > Jul 5 04:06:43 dom0 kernel: [23043.137159] [<ffffffff8101d204>] ? > > xen_load_sp0+0x84/0x180 > > Jul 5 04:06:43 dom0 kernel: [23043.137162] [<ffffffff810ca961>] ? > > __raw_callee_save___pv_queued_spin_unlock+0x11/0x20 > > Jul 5 04:06:43 dom0 kernel: [23043.137165] [<ffffffffc04ec245>] > > __do_block_io_op+0x395/0x710 [xen_blkback] > > Jul 5 04:06:43 dom0 kernel: [23043.137167] [<ffffffff810ec8a8>] ? > > del_timer_sync+0x48/0x50 > > Jul 5 04:06:43 dom0 kernel: [23043.137170] [<ffffffffc04eca7d>] > > xen_blkif_schedule+0xdd/0x7b0 [xen_blkback] > > Jul 5 04:06:43 dom0 kernel: [23043.137172] [<ffffffff810a975d>] ? > > finish_task_switch+0x7d/0x220 > > Jul 5 04:06:43 dom0 kernel: [23043.137175] [<ffffffff810c3ca0>] ? > > wake_atomic_t_function+0x60/0x60 > > Jul 5 04:06:43 dom0 kernel: [23043.137177] [<ffffffffc04ec9a0>] ? > > xen_blkif_be_int+0x30/0x30 [xen_blkback] > > Jul 5 04:06:43 dom0 kernel: [23043.137179] [<ffffffff810a0808>] > > kthread+0xd8/0xf0 > > Jul 5 04:06:43 dom0 kernel: [23043.137181] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:06:43 dom0 kernel: [23043.137183] [<ffffffff81827a4f>] > > ret_from_fork+0x3f/0x70 > > Jul 5 04:06:43 dom0 kernel: [23043.137185] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > > > At the same time (but always after bcache), Xen's blkback will also > > give a similar message: > > > > Jul 5 04:08:43 dom0 kernel: [23163.135027] INFO: task > > bcache_writebac:1342 blocked for more than 120 seconds. > > Jul 5 04:08:43 dom0 kernel: [23163.135056] Not tainted > > 4.4.0-28-generic #47-Ubuntu > > Jul 5 04:08:43 dom0 kernel: [23163.135076] "echo 0 > > > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > > Jul 5 04:08:43 dom0 kernel: [23163.135105] bcache_writebac D > > ffff880000983d18 0 1342 2 0x00000000 > > Jul 5 04:08:43 dom0 kernel: [23163.135109] ffff880000983d18 > > 0000000000007ff0 ffffffff81e11500 ffff880035705780 > > Jul 5 04:08:43 dom0 kernel: [23163.135112] ffff880000984000 > > ffff880005080af0 ffff880005080ad8 ffffffff00000000 > > Jul 5 04:08:43 dom0 kernel: [23163.135114] ffffffff00000003 > > ffff880000983d30 ffffffff818235b5 ffff880035705780 > > Jul 5 04:08:43 dom0 kernel: [23163.135116] Call Trace: > > Jul 5 04:08:43 dom0 kernel: [23163.135124] [<ffffffff818235b5>] > > schedule+0x35/0x80 > > Jul 5 04:08:43 dom0 kernel: [23163.135127] [<ffffffff81826202>] > > rwsem_down_write_failed+0x202/0x350 > > Jul 5 04:08:43 dom0 kernel: [23163.135139] [<ffffffffc015e6d0>] ? > > read_dirty+0x370/0x370 [bcache] > > Jul 5 04:08:43 dom0 kernel: [23163.135143] [<ffffffff813f9643>] > > call_rwsem_down_write_failed+0x13/0x20 > > Jul 5 04:08:43 dom0 kernel: [23163.135145] [<ffffffff81825a3d>] ? > > down_write+0x2d/0x40 > > Jul 5 04:08:43 dom0 kernel: [23163.135153] [<ffffffffc015e72b>] > > bch_writeback_thread+0x5b/0x4c0 [bcache] > > Jul 5 04:08:43 dom0 kernel: [23163.135160] [<ffffffffc015e6d0>] ? > > read_dirty+0x370/0x370 [bcache] > > Jul 5 04:08:43 dom0 kernel: [23163.135162] [<ffffffff810a0808>] > > kthread+0xd8/0xf0 > > Jul 5 04:08:43 dom0 kernel: [23163.135164] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:08:43 dom0 kernel: [23163.135166] [<ffffffff81827a4f>] > > ret_from_fork+0x3f/0x70 > > Jul 5 04:08:43 dom0 kernel: [23163.135168] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:08:43 dom0 kernel: [23163.135178] INFO: task > > blkback.5.hda:3357 blocked for more than 120 seconds. > > Jul 5 04:08:43 dom0 kernel: [23163.135204] Not tainted > > 4.4.0-28-generic #47-Ubuntu > > Jul 5 04:08:43 dom0 kernel: [23163.135224] "echo 0 > > > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > > Jul 5 04:08:43 dom0 kernel: [23163.135286] blkback.5.hda D > > ffff88002341ba48 0 3357 2 0x00000000 > > Jul 5 04:08:43 dom0 kernel: [23163.135289] ffff88002341ba48 > > ffff88002341ba08 ffffffff81e11500 ffff880034189900 > > Jul 5 04:08:43 dom0 kernel: [23163.135291] ffff88002341c000 > > ffff880005080ad8 ffff880005080af0 ffff880023e08e60 > > Jul 5 04:08:43 dom0 kernel: [23163.135293] ffff880005080000 > > ffff88002341ba60 ffffffff818235b5 ffff880034189900 > > Jul 5 04:08:43 dom0 kernel: [23163.135295] Call Trace: > > Jul 5 04:08:43 dom0 kernel: [23163.135299] [<ffffffff818235b5>] > > schedule+0x35/0x80 > > Jul 5 04:08:43 dom0 kernel: [23163.135301] [<ffffffff81826430>] > > rwsem_down_read_failed+0xe0/0x140 > > Jul 5 04:08:43 dom0 kernel: [23163.135304] [<ffffffff811903e5>] ? > > mempool_alloc_slab+0x15/0x20 > > Jul 5 04:08:43 dom0 kernel: [23163.135307] [<ffffffff813f9614>] > > call_rwsem_down_read_failed+0x14/0x30 > > Jul 5 04:08:43 dom0 kernel: [23163.135309] [<ffffffff81825a00>] ? > > down_read+0x20/0x30 > > Jul 5 04:08:43 dom0 kernel: [23163.135316] [<ffffffffc01522a2>] > > cached_dev_make_request+0x682/0xcc0 [bcache] > > Jul 5 04:08:43 dom0 kernel: [23163.135319] [<ffffffff813bba52>] > > generic_make_request+0xf2/0x1d0 > > Jul 5 04:08:43 dom0 kernel: [23163.135321] [<ffffffff813bbba6>] > > submit_bio+0x76/0x170 > > Jul 5 04:08:43 dom0 kernel: [23163.135326] [<ffffffffc04ebbb7>] > > dispatch_rw_block_io+0x7b7/0xab0 [xen_blkback] > > Jul 5 04:08:43 dom0 kernel: [23163.135328] [<ffffffff8101d204>] ? > > xen_load_sp0+0x84/0x180 > > Jul 5 04:08:43 dom0 kernel: [23163.135331] [<ffffffff810ca961>] ? > > __raw_callee_save___pv_queued_spin_unlock+0x11/0x20 > > Jul 5 04:08:43 dom0 kernel: [23163.135334] [<ffffffffc04ec245>] > > __do_block_io_op+0x395/0x710 [xen_blkback] > > Jul 5 04:08:43 dom0 kernel: [23163.135337] [<ffffffff810ec8a8>] ? > > del_timer_sync+0x48/0x50 > > Jul 5 04:08:43 dom0 kernel: [23163.135340] [<ffffffffc04eca7d>] > > xen_blkif_schedule+0xdd/0x7b0 [xen_blkback] > > Jul 5 04:08:43 dom0 kernel: [23163.135343] [<ffffffff810a975d>] ? > > finish_task_switch+0x7d/0x220 > > Jul 5 04:08:43 dom0 kernel: [23163.135346] [<ffffffff810c3ca0>] ? > > wake_atomic_t_function+0x60/0x60 > > Jul 5 04:08:43 dom0 kernel: [23163.135348] [<ffffffffc04ec9a0>] ? > > xen_blkif_be_int+0x30/0x30 [xen_blkback] > > Jul 5 04:08:43 dom0 kernel: [23163.135350] [<ffffffff810a0808>] > > kthread+0xd8/0xf0 > > Jul 5 04:08:43 dom0 kernel: [23163.135352] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > Jul 5 04:08:43 dom0 kernel: [23163.135354] [<ffffffff81827a4f>] > > ret_from_fork+0x3f/0x70 > > Jul 5 04:08:43 dom0 kernel: [23163.135356] [<ffffffff810a0730>] ? > > kthread_create_on_node+0x1e0/0x1e0 > > > > Access to the storage is no longer possible, then (it'll just appear to hang). > > This is on the newest Ubuntu 16.04 LTS, with their 4.4.0-28 kernel. > > > > # lsb_release -d > > Description: Ubuntu 16.04 LTS > > # uname -r > > 4.4.0-28-generic > > > > bcache is set to writeback. > > > > # cat /sys/block/bcache0/bcache/cache_mode > > writethrough [writeback] writearound none > > # cat /sys/block/bcache0/bcache/state > > dirty > > # cat /sys/block/bcache0/bcache/dirty_data > > 56.0k > > > > The relevant disk stack looks like this: > > > > # lsblk > > sdd 8:48 0 232.9G 0 disk > > `-sdd1 8:49 0 232.9G 0 part > > `-md1 9:1 0 232.8G 0 raid1 > > `-ssd-bcache--back 252:4 0 30G 0 lvm > > `-bcache0 251:0 0 2T 0 disk > > `-storage-drback--test 252:6 0 200G 0 lvm > > > > storage-drback--test is the backing device for DRBD. > > > > This is reproducible, but I do not know what causes it, or how to > > cause it on purpose. All I know is that once I put DRBD on top of > > bcache, and produce minor load over time (I just have a single idle > > Windows 2012R2 server on it as test - as Windows would always do > > *something* ;-) it will lock up within 8 hours. > > > > Do you have any clues as to what could be causing this? > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
