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INFO: task hung in __writeback_inodes_sb_nr

Status: auto-closed as invalid on 2019/04/08 13:33
First crash: 2161d, last: 2018d
Similar bugs (13)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in __writeback_inodes_sb_nr fs 53 1921d 2184d 0/26 closed as dup on 2018/09/08 15:33
android-414 INFO: task hung in __writeback_inodes_sb_nr 1 1955d 1832d 0/1 auto-closed as invalid on 2019/06/09 16:55
upstream INFO: task hung in __writeback_inodes_sb_nr (5) ext4 C done 48 426d 797d 22/26 fixed on 2023/02/24 13:50
linux-5.15 INFO: task hung in __writeback_inodes_sb_nr origin:lts-only C done 1495 25d 406d 0/3 upstream: reported C repro on 2023/03/09 17:32
linux-6.1 INFO: task hung in __writeback_inodes_sb_nr (2) 4 3d04h 111d 0/3 upstream: reported on 2023/12/30 04:30
linux-4.19 INFO: task hung in __writeback_inodes_sb_nr ext4 4 421d 568d 0/1 upstream: reported on 2022/09/28 21:19
linux-6.1 INFO: task hung in __writeback_inodes_sb_nr 1 245d 245d 0/3 auto-obsoleted due to no activity on 2023/11/26 06:37
upstream INFO: task hung in __writeback_inodes_sb_nr (6) ext4 C done 78 98d 307d 1/26 upstream: reported C repro on 2023/06/17 00:33
upstream INFO: task hung in __writeback_inodes_sb_nr (4) ext4 4 805d 859d 0/26 closed as invalid on 2022/02/08 10:10
upstream INFO: task hung in __writeback_inodes_sb_nr (3) ext4 2 1071d 1169d 0/26 auto-closed as invalid on 2021/08/11 17:49
linux-4.14 INFO: task hung in __writeback_inodes_sb_nr (2) 2 537d 538d 0/1 auto-obsoleted due to no activity on 2023/02/27 15:30
upstream INFO: task hung in __writeback_inodes_sb_nr (2) ext4 1 1353d 1353d 0/26 auto-closed as invalid on 2020/11/03 06:13
linux-4.14 INFO: task hung in __writeback_inodes_sb_nr 1 1419d 1419d 0/1 auto-closed as invalid on 2020/09/27 19:31

Sample crash report:
IPVS: length: 193 != 8
IPVS: length: 193 != 8
INFO: task syz-executor0:3720 blocked for more than 140 seconds.
      Not tainted 4.9.124-g09eb2ba #31
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D27240  3720      1 0x00000004
 ffff8801c412e000 ffff8801c5df6a00 ffff8801c5a6df80 ffff8801c5214800
 ffff8801db321c18 ffff8801a13d7b40 ffffffff839f0afd 0000000000000002
 0000000041b58ab3 ffffffff843bbc94 00ffffff81223870 ffff8801db3224e8
Call Trace:
 [<ffffffff839f20ff>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff816073d9>] wb_wait_for_completion+0x149/0x1b0 fs/fs-writeback.c:221
 [<ffffffff81607647>] __writeback_inodes_sb_nr+0x207/0x300 fs/fs-writeback.c:2310
 [<ffffffff81607797>] writeback_inodes_sb_nr fs/fs-writeback.c:2327 [inline]
 [<ffffffff81607797>] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2342
 [<ffffffff8161f353>] __sync_filesystem fs/sync.c:35 [inline]
 [<ffffffff8161f353>] sync_filesystem+0x93/0x240 fs/sync.c:63
 [<ffffffff8157ddc5>] generic_shutdown_super+0x75/0x300 fs/super.c:423
 [<ffffffff8157e6ff>] kill_block_super+0x9f/0x120 fs/super.c:1127
 [<ffffffff8157ea75>] deactivate_locked_super+0x75/0xd0 fs/super.c:310
 [<ffffffff8157f481>] deactivate_super+0x91/0xd0 fs/super.c:341
 [<ffffffff815e1692>] cleanup_mnt+0xb2/0x160 fs/namespace.c:1143
 [<ffffffff815e17c6>] __cleanup_mnt+0x16/0x20 fs/namespace.c:1150
 [<ffffffff8119a66c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff8100559c>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100559c>] exit_to_usermode_loop+0xfc/0x120 arch/x86/entry/common.c:161
 [<ffffffff810064d4>] prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 [<ffffffff810064d4>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff810064d4>] do_syscall_64+0x364/0x490 arch/x86/entry/common.c:287
 [<ffffffff83a019d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813689dc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813689dc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81428248>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3624:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839ffba2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82125402>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor0/3720:
 #0:  (&type->s_umount_key#40){+.+...}, at: [<ffffffff8157f479>] deactivate_super+0x89/0xd0 fs/super.c:340

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8787d08 ffffffff81eb95e9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d8787d40
 ffffffff81ec4927 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb95e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb95e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec4927>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec48ba>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810ba0a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81368f74>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81368f74>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368f74>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368f74>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01b9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 114 Comm: kworker/u4:2 Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfnc (flush-7:0)c
task: ffff8801d9688000 task.stack: ffff8801d9760000
RIP: 0010:[<ffffffff81232d3d>] c [<ffffffff81232d3d>] lock_is_held+0xdd/0x140 kernel/locking/lockdep.c:3795
RSP: 0018:ffff8801d9767610  EFLAGS: 00000807
RAX: dffffc0000000000 RBX: 0000000000000246 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff846df4a0 RDI: ffff8801d96888c4
RBP: ffff8801d9767628 R08: ffff8801d9688960 R09: 0000000000000001
R10: ffff8801d9688000 R11: 1ffff1003b2d1127 R12: ffff8801d9688000
R13: 0000000000000001 R14: 0000000002420848 R15: ffff8801d9c17688
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff243ef5000 CR3: 00000001c7b23000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffea0006c84e00c ffff8801c9ae5628c dffffc0000000000c ffff8801d9767638c
 ffffffff8127e464c ffff8801d97676a0c ffffffff8143b3dbc ffffffff8143b090c
 ffffffff816288d3c ffff8801d9c17554c 0000000000000000c ffff8801d9c17690c
Call Trace:
 [<ffffffff8127e464>] rcu_read_lock_held+0xa4/0xc0 kernel/rcu/update.c:297
 [<ffffffff8143b3db>] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline]
 [<ffffffff8143b3db>] find_get_entry+0x34b/0x540 mm/filemap.c:1095
 [<ffffffff8143c50b>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1201
 [<ffffffff81629ba9>] find_or_create_page include/linux/pagemap.h:309 [inline]
 [<ffffffff81629ba9>] grow_dev_page fs/buffer.c:1005 [inline]
 [<ffffffff81629ba9>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81629ba9>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81629ba9>] __getblk_gfp+0x249/0x710 fs/buffer.c:1386
 [<ffffffff8162d48d>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818db771>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818db771>] fat_clusters_flush+0x111/0x380 fs/fat/misc.c:69
 [<ffffffff818d56d2>] fat_write_inode+0xf2/0x170 fs/fat/inode.c:898
 [<ffffffff81606add>] write_inode fs/fs-writeback.c:1180 [inline]
 [<ffffffff81606add>] __writeback_single_inode+0x86d/0x1020 fs/fs-writeback.c:1379
 [<ffffffff81607ddc>] writeback_sb_inodes+0x4ac/0xe70 fs/fs-writeback.c:1584
 [<ffffffff81608ddf>] wb_writeback+0x2cf/0xbd0 fs/fs-writeback.c:1760
 [<ffffffff8161230e>] wb_do_writeback fs/fs-writeback.c:1894 [inline]
 [<ffffffff8161230e>] wb_workfn+0x20e/0xdb0 fs/fs-writeback.c:1930
 [<ffffffff8118f461>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff81190256>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01b9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Code: cff cff c65 c4c c8b c24 c25 cc0 c7d c01 c00 c49 c8d cbc c24 cc4 c08 c00 c00 c41 c89 cc5 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 cfa c48 cc1 cea c03 c0f cb6 c14 c02 c<48> c89 cf8 c83 ce0 c07 c83 cc0 c03 c38 cd0 c7c c04 c84 cd2 c75 c3a c41 cc7 c84 c24 c

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/29 13:57 https://android.googlesource.com/kernel/common android-4.9 09eb2ba5ed0c 53ff8784 .config console log report ci-android-49-kasan-gce-root
2018/08/28 13:06 https://android.googlesource.com/kernel/common android-4.9 09eb2ba5ed0c 7ef1de9e .config console log report ci-android-49-kasan-gce-root
2018/08/22 04:39 https://android.googlesource.com/kernel/common android-4.9 54068d61e7d8 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/21 23:09 https://android.googlesource.com/kernel/common android-4.9 54068d61e7d8 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/18 13:21 https://android.googlesource.com/kernel/common android-4.9 681e57bb080a db1858f6 .config console log report ci-android-49-kasan-gce-root
2018/08/14 16:58 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 5084a625 .config console log report ci-android-49-kasan-gce-root
2018/08/13 09:07 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
2018/08/10 18:20 https://android.googlesource.com/kernel/common android-4.9 92e87041ed2d 1fb62d58 .config console log report ci-android-49-kasan-gce-root
2018/08/05 04:47 https://android.googlesource.com/kernel/common android-4.9 8b21e85d919c 3476a2df .config console log report ci-android-49-kasan-gce-root
2018/07/23 10:21 https://android.googlesource.com/kernel/common android-4.9 47bbcd6bf8f9 f69c5fcd .config console log report ci-android-49-kasan-gce-root
2018/07/23 05:21 https://android.googlesource.com/kernel/common android-4.9 47bbcd6bf8f9 8cc079c3 .config console log report ci-android-49-kasan-gce-root
2018/07/19 00:00 https://android.googlesource.com/kernel/common android-4.9 47bbcd6bf8f9 49f35839 .config console log report ci-android-49-kasan-gce-root
2018/07/17 22:42 https://android.googlesource.com/kernel/common android-4.9 f540ce029f50 6d5bd5b5 .config console log report ci-android-49-kasan-gce-root
2018/07/08 17:47 https://android.googlesource.com/kernel/common android-4.9 03c70feafdb2 c9a7a4dc .config console log report ci-android-49-kasan-gce-root
2018/07/08 14:13 https://android.googlesource.com/kernel/common android-4.9 03c70feafdb2 c9a7a4dc .config console log report ci-android-49-kasan-gce-root
2018/07/06 08:30 https://android.googlesource.com/kernel/common android-4.9 03c70feafdb2 18403e65 .config console log report ci-android-49-kasan-gce-root
2018/06/17 16:00 https://android.googlesource.com/kernel/common android-4.9 a4230beab30a 27c5f59f .config console log report ci-android-49-kasan-gce-root
2018/06/16 12:32 https://android.googlesource.com/kernel/common android-4.9 a4230beab30a 27c5f59f .config console log report ci-android-49-kasan-gce-root
2018/06/13 00:55 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 6dcbc435 .config console log report ci-android-49-kasan-gce-root
2018/06/10 23:43 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 866118af .config console log report ci-android-49-kasan-gce-root
2018/06/09 01:36 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 866118af .config console log report ci-android-49-kasan-gce-root
2018/05/23 12:33 https://android.googlesource.com/kernel/common android-4.9 d054505522c4 f48c20b8 .config console log report ci-android-49-kasan-gce-root
2018/05/20 06:26 https://android.googlesource.com/kernel/common android-4.9 aef17a58e8ca f48c20b8 .config console log report ci-android-49-kasan-gce-root
2018/10/10 13:28 https://android.googlesource.com/kernel/common android-4.9 7bebf33f9d46 5b11ac2c .config console log report ci-android-49-kasan-gce-386
2018/09/27 20:55 https://android.googlesource.com/kernel/common android-4.9 aa4de6f13f5d 0c2fa87b .config console log report ci-android-49-kasan-gce-386
2018/09/25 20:59 https://android.googlesource.com/kernel/common android-4.9 36daaf708bc0 b7e11289 .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.