From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Wiele Subject: Hang in bcache/qemu Date: Wed, 11 Jan 2017 18:34:17 +0100 Message-ID: <2059985.veGUll5WnS@j-t460p> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from fabrik17.de ([78.47.224.236]:55861 "EHLO mail.fabrik17.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030963AbdAKRjq (ORCPT ); Wed, 11 Jan 2017 12:39:46 -0500 Received: from j-t460p.localnet (unknown [134.147.202.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.fabrik17.de (Postfix) with ESMTPSA id 60E6761AAF for ; Wed, 11 Jan 2017 18:34:07 +0100 (CET) Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: linux-bcache@vger.kernel.org Hi, I'm experiencing a possible bcache-hang in my setup. Mainboard: Asrock Rack EP2C602 CPU: 2x Intel Xeon E5-2670 Linux: 4.8.13-1-ARCH Cache-device: Partition on Samsung SSD 850 EVO 500GB Backing-device: 500GB Western Digital Black Bcache is running in writeback mode. On top of bcache, I'm running LVM, which provides a Games-LV for a Qemu Windows-10 VM (Games-HD with drive letter 'D'. Drive C is hosted on a non-bcache block device. Each VM has its own GPU via passthrough). For a second/third VM, I create snapshots of the Games-LV. When playing the game Overwatch, the first VM suddenly stops to respond (after about >20min), some seconds later the second VM, too. Currently I'm not near the machine with the problem, but I'm appending as much information as possible. Regards, Jan $ bcache-super-show /dev/sdb6 sb.magic ok sb.first_sector 8 [match] sb.csum 617AC6C2ABF15A0D [match] sb.version 3 [cache device] dev.label (empty) dev.uuid 73ec71d1-1353-4cc0-8b06-d798b44d593e dev.sectors_per_block 1 dev.sectors_per_bucket 1024 dev.cache.first_sector 1024 dev.cache.cache_sectors 204692480 dev.cache.total_sectors 204693504 dev.cache.ordered yes dev.cache.discard no dev.cache.pos 0 dev.cache.replacement 0 [lru] cset.uuid 025ec95a-c03b-481f-97e4-d6dab92ba6b1 $ dmesg [...] [ 3945.367318] INFO: task kworker/22:0:146 blocked for more than 120 seconds. [ 3945.369245] Not tainted 4.8.13-1-ARCH #1 [ 3945.371113] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 3945.372970] kworker/22:0 D ffff88046d2c3cd8 0 146 2 0x00000000 [ 3945.372982] Workqueue: events update_writeback_rate [bcache] [ 3945.372983] ffff88046d2c3cd8 00ff88046d2c3cd0 ffff88046148e3c0 ffff88046d270e40 [ 3945.372986] ffff88046fd97ff0 ffff88046d2c4000 ffff8804696f0ad8 ffff88046d2c3d10 [ 3945.372988] ffff8804696f0af0 ffff8804696f0b18 ffff88046d2c3cf0 ffffffff815f40ec [ 3945.372990] Call Trace: [ 3945.372995] [] schedule+0x3c/0x90 [ 3945.372997] [] rwsem_down_read_failed+0xf9/0x150 [ 3945.372999] [] call_rwsem_down_read_failed+0x18/0x30 [ 3945.373000] [] down_read+0x17/0x30 [ 3945.373004] [] update_writeback_rate+0x25/0x210 [bcache] [ 3945.373006] [] process_one_work+0x1e5/0x470 [ 3945.373008] [] worker_thread+0x48/0x4e0 [ 3945.373009] [] ? process_one_work+0x470/0x470 [ 3945.373011] [] kthread+0xd8/0xf0 [ 3945.373014] [] ? __switch_to+0x2d2/0x630 [ 3945.373016] [] ret_from_fork+0x1f/0x40 [ 3945.373018] [] ? kthread_worker_fn+0x170/0x170 [ 3945.373031] INFO: task bcache_writebac:343 blocked for more than 120 seconds. [ 3945.374945] Not tainted 4.8.13-1-ARCH #1 [ 3945.376837] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 3945.378724] bcache_writebac D ffff88046975fcb8 0 343 2 0x00000000 [ 3945.378735] ffff88046975fcb8 00ff88046fa17f80 ffffffff81a0d500 ffff88046978d580 [ 3945.378737] ffff88046978d500 ffff880469760000 ffff8804696f0ad8 ffff8804696f0ad8 [ 3945.378740] ffff8804696f0af0 ffffffff00000001 ffff88046975fcd0 ffffffff815f40ec [ 3945.378742] Call Trace: [ 3945.378744] [] schedule+0x3c/0x90 [ 3945.378746] [] rwsem_down_write_failed+0x132/0x2b0 [ 3945.378748] [] call_rwsem_down_write_failed+0x17/0x30 [ 3945.378750] [] down_write+0x24/0x40 [ 3945.378754] [] bch_writeback_thread+0x6b/0x7f0 [bcache] [ 3945.378758] [] ? write_dirty+0xb0/0xb0 [bcache] [ 3945.378762] [] kthread+0xd8/0xf0 [ 3945.378763] [] ? __switch_to+0x2d2/0x630 [ 3945.378765] [] ret_from_fork+0x1f/0x40 [ 3945.378767] [] ? kthread_worker_fn+0x170/0x170 [ 3945.378777] INFO: task qemu-system-x86:829 blocked for more than 120 seconds. [ 3945.380619] Not tainted 4.8.13-1-ARCH #1 [ 3945.382501] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 3945.385458] qemu-system-x86 D ffff88046933b7a8 0 829 1 0x00000000 [ 3945.385461] ffff88046933b7a8 00ff88046933b7b0 ffff8808650faac0 ffff88086ab52ac0 [ 3945.385463] 8000000000000000 ffff88046933c000 ffff8804696f0ad8 ffff88046933b7e0 [ 3945.385465] ffff8804696f0af0 ffff8804696f0000 ffff88046933b7c0 ffffffff815f40ec [ 3945.385467] Call Trace: [ 3945.385470] [] schedule+0x3c/0x90 [ 3945.385471] [] rwsem_down_read_failed+0xf9/0x150 [ 3945.385475] [] ? bch_submit_bbio+0x2b/0x30 [bcache] [ 3945.385477] [] call_rwsem_down_read_failed+0x18/0x30 [ 3945.385478] [] down_read+0x17/0x30 [ 3945.385482] [] cached_dev_make_request+0x63b/0xcb0 [bcache] [ 3945.385485] [] generic_make_request+0xf2/0x1a0 [ 3945.385487] [] submit_bio+0x7d/0x150 [ 3945.385490] [] __blockdev_direct_IO+0x31a3/0x4040 [ 3945.385493] [] ? poll_freewait+0x8d/0xb0 [ 3945.385495] [] ? I_BDEV+0x20/0x20 [ 3945.385497] [] blkdev_direct_IO+0x43/0x50 [ 3945.385500] [] generic_file_direct_write+0xb4/0x170 [ 3945.385502] [] __generic_file_write_iter+0xbb/0x1d0 [ 3945.385504] [] ? __check_object_size+0x54/0x1d6 [ 3945.385506] [] ? bd_acquire+0xb0/0xb0 [ 3945.385508] [] blkdev_write_iter+0x8b/0x100 [ 3945.385509] [] ? bd_acquire+0xb0/0xb0 [ 3945.385511] [] ? import_iovec+0x3a/0xe0 [ 3945.385514] [] aio_run_iocb+0x247/0x2c0 [ 3945.385516] [] ? eventfd_ctx_read+0x166/0x1e0 [ 3945.385518] [] ? poll_select_copy_remaining+0x150/0x150 [ 3945.385519] [] ? wake_up_q+0x80/0x80 [ 3945.385521] [] ? __fget+0x77/0xb0 [ 3945.385522] [] ? __fget_light+0x25/0x60 [ 3945.385524] [] ? __fdget+0x13/0x20 [ 3945.385526] [] do_io_submit+0x364/0x590 [ 3945.385528] [] SyS_io_submit+0x10/0x20 [ 3945.385530] [] entry_SYSCALL_64_fastpath+0x1a/0xa4 [ 4068.241562] INFO: task kworker/22:0:146 blocked for more than 120 seconds. [ 4068.243485] Not tainted 4.8.13-1-ARCH #1 [ 4068.245395] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 4068.247346] kworker/22:0 D ffff88046d2c3cd8 0 146 2 0x00000000 [ 4068.247354] Workqueue: events update_writeback_rate [bcache] [ 4068.247355] ffff88046d2c3cd8 00ff88046d2c3cd0 ffff88046148e3c0 ffff88046d270e40 [ 4068.247358] ffff88046fd97ff0 ffff88046d2c4000 ffff8804696f0ad8 ffff88046d2c3d10 [ 4068.247360] ffff8804696f0af0 ffff8804696f0b18 ffff88046d2c3cf0 ffffffff815f40ec [ 4068.247406] Call Trace: [ 4068.247409] [] schedule+0x3c/0x90 [ 4068.247411] [] rwsem_down_read_failed+0xf9/0x150 [ 4068.247413] [] call_rwsem_down_read_failed+0x18/0x30 [ 4068.247415] [] down_read+0x17/0x30 [ 4068.247418] [] update_writeback_rate+0x25/0x210 [bcache] [ 4068.247421] [] process_one_work+0x1e5/0x470 [ 4068.247422] [] worker_thread+0x48/0x4e0 [ 4068.247424] [] ? process_one_work+0x470/0x470 [ 4068.247426] [] kthread+0xd8/0xf0 [ 4068.247427] [] ? __switch_to+0x2d2/0x630 [ 4068.247429] [] ret_from_fork+0x1f/0x40 [ 4068.247432] [] ? kthread_worker_fn+0x170/0x170 [ 4068.247439] INFO: task bcache_writebac:343 blocked for more than 120 seconds. [ 4068.249394] Not tainted 4.8.13-1-ARCH #1 [ 4068.251285] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 4068.253194] bcache_writebac D ffff88046975fcb8 0 343 2 0x00000000 [ 4068.253196] ffff88046975fcb8 00ff88046fa17f80 ffffffff81a0d500 ffff88046978d580 [ 4068.253199] ffff88046978d500 ffff880469760000 ffff8804696f0ad8 ffff8804696f0ad8 [ 4068.253201] ffff8804696f0af0 ffffffff00000001 ffff88046975fcd0 ffffffff815f40ec [ 4068.253203] Call Trace: [ 4068.253205] [] schedule+0x3c/0x90 [ 4068.253207] [] rwsem_down_write_failed+0x132/0x2b0 [ 4068.253209] [] call_rwsem_down_write_failed+0x17/0x30 [ 4068.253211] [] down_write+0x24/0x40 [ 4068.253214] [] bch_writeback_thread+0x6b/0x7f0 [bcache] [ 4068.253218] [] ? write_dirty+0xb0/0xb0 [bcache] [ 4068.253220] [] kthread+0xd8/0xf0 [ 4068.253221] [] ? __switch_to+0x2d2/0x630 [ 4068.253223] [] ret_from_fork+0x1f/0x40 [ 4068.253225] [] ? kthread_worker_fn+0x170/0x170 [ 4068.253230] INFO: task qemu-system-x86:829 blocked for more than 120 seconds. [ 4068.255137] Not tainted 4.8.13-1-ARCH #1 [ 4068.256969] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 4068.258844] qemu-system-x86 D ffff88046933b7a8 0 829 1 0x00000000 [ 4068.258846] ffff88046933b7a8 00ff88046933b7b0 ffff8808650faac0 ffff88086ab52ac0 [ 4068.258848] 8000000000000000 ffff88046933c000 ffff8804696f0ad8 ffff88046933b7e0 [ 4068.258850] ffff8804696f0af0 ffff8804696f0000 ffff88046933b7c0 ffffffff815f40ec [ 4068.258853] Call Trace: [ 4068.258855] [] schedule+0x3c/0x90 [ 4068.258856] [] rwsem_down_read_failed+0xf9/0x150 [ 4068.258861] [] ? bch_submit_bbio+0x2b/0x30 [bcache] [ 4068.258863] [] call_rwsem_down_read_failed+0x18/0x30 [ 4068.258866] [] down_read+0x17/0x30 [ 4068.258870] [] cached_dev_make_request+0x63b/0xcb0 [bcache] [ 4068.258872] [] generic_make_request+0xf2/0x1a0 [ 4068.258874] [] submit_bio+0x7d/0x150 [ 4068.258877] [] __blockdev_direct_IO+0x31a3/0x4040 [ 4068.258879] [] ? poll_freewait+0x8d/0xb0 [ 4068.258881] [] ? I_BDEV+0x20/0x20 [ 4068.258883] [] blkdev_direct_IO+0x43/0x50 [ 4068.258886] [] generic_file_direct_write+0xb4/0x170 [ 4068.258887] [] __generic_file_write_iter+0xbb/0x1d0 [ 4068.258889] [] ? __check_object_size+0x54/0x1d6 [ 4068.258891] [] ? bd_acquire+0xb0/0xb0 [ 4068.258892] [] blkdev_write_iter+0x8b/0x100 [ 4068.258894] [] ? bd_acquire+0xb0/0xb0 [ 4068.258896] [] ? import_iovec+0x3a/0xe0 [ 4068.258898] [] aio_run_iocb+0x247/0x2c0 [ 4068.258900] [] ? eventfd_ctx_read+0x166/0x1e0 [ 4068.258901] [] ? poll_select_copy_remaining+0x150/0x150 [ 4068.258903] [] ? wake_up_q+0x80/0x80 [ 4068.258904] [] ? __fget+0x77/0xb0 [ 4068.258906] [] ? __fget_light+0x25/0x60 [ 4068.258908] [] ? __fdget+0x13/0x20 [ 4068.258911] [] do_io_submit+0x364/0x590 [ 4068.258913] [] SyS_io_submit+0x10/0x20 [ 4068.258915] [] entry_SYSCALL_64_fastpath+0x1a/0xa4 [ 4068.258917] INFO: task qemu-system-x86:903 blocked for more than 120 seconds. [ 4068.260756] Not tainted 4.8.13-1-ARCH #1 [ 4068.262646] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 4068.264530] qemu-system-x86 D ffff8802966b77a8 0 903 1 0x00000000 [ 4068.264533] ffff8802966b77a8 00ff88086ab53900 ffff880460a1c740 ffff88086ab53900 [ 4068.264535] ffff8802966b77f8 ffff8802966b8000 ffff8804696f0ad8 ffff8802966b77e0 [ 4068.264537] ffff8804696f0af0 ffff8804696f0000 ffff8802966b77c0 ffffffff815f40ec [ 4068.264539] Call Trace: [ 4068.264541] [] schedule+0x3c/0x90 [ 4068.264543] [] rwsem_down_read_failed+0xf9/0x150 [ 4068.264545] [] call_rwsem_down_read_failed+0x18/0x30 [ 4068.264546] [] down_read+0x17/0x30 [ 4068.264550] [] cached_dev_make_request+0x63b/0xcb0 [bcache] [ 4068.264552] [] generic_make_request+0xf2/0x1a0 [ 4068.264554] [] submit_bio+0x7d/0x150 [ 4068.264556] [] __blockdev_direct_IO+0x31a3/0x4040 [ 4068.264558] [] ? poll_freewait+0x8d/0xb0 [ 4068.264560] [] ? I_BDEV+0x20/0x20 [ 4068.264562] [] blkdev_direct_IO+0x43/0x50 [ 4068.264564] [] generic_file_direct_write+0xb4/0x170 [ 4068.264566] [] __generic_file_write_iter+0xbb/0x1d0 [ 4068.264567] [] ? __check_object_size+0x54/0x1d6 [ 4068.264569] [] ? bd_acquire+0xb0/0xb0 [ 4068.264571] [] blkdev_write_iter+0x8b/0x100 [ 4068.264573] [] ? bd_acquire+0xb0/0xb0 [ 4068.264574] [] ? import_iovec+0x3a/0xe0 [ 4068.264576] [] aio_run_iocb+0x247/0x2c0 [ 4068.264579] [] ? set_next_entity+0x4c/0x940 [ 4068.264581] [] ? put_prev_entity+0xb4/0x8c0 [ 4068.264582] [] ? __fget+0x77/0xb0 [ 4068.264583] [] ? __fget_light+0x25/0x60 [ 4068.264585] [] ? __fdget+0x13/0x20 [ 4068.264587] [] do_io_submit+0x364/0x590 [ 4068.264589] [] SyS_io_submit+0x10/0x20 [ 4068.264590] [] entry_SYSCALL_64_fastpath+0x1a/0xa4