On Thu, 14 Jul 2016, Stefan Priebe - Profihost AG wrote: > Am 13.07.2016 um 23:18 schrieb Eric Wheeler: > > On Wed, 13 Jul 2016, Stefan Priebe - Profihost AG wrote: > > > >> > >> Am 13.07.2016 um 08:18 schrieb Eric Wheeler: > >>> 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 > >>> > >>> C. [1/3] block: flush queued bios when process blocks to avoid deadlock > >>> by Mikulas Patocka: https://patchwork.kernel.org/patch/9204125/ > >>> > >>> 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. > >>> > >> > >> Just want to let you now that here is stated that this does not always > >> fix C also a backport to 4.4 and others is currently missing: > >> https://bugzilla.kernel.org/show_bug.cgi?id=119841 > > > > Interesting, so Mikulas' "C" with threading/timer is fixing things that > > Lars' "E" did not? Well, here's hoping for a good fix. There are a lot > > of great developers working on this. More detail here: > > https://www.redhat.com/archives/dm-devel/2016-June/msg00425.html > > Yes that it makes it really complicated to know which patches to apply > to 4.4. Do you have any patches other than those above that should be included in the list for v4.3+ stability? -- Eric Wheeler > > Greets, > Stefan > > > > > > > -- > > Eric Wheeler > > > > > >> > >> Stefan > >> > >>> 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 > >>> > >> > -- > 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
