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INFO: task hung in deactivate_super

Status: auto-closed as invalid on 2019/02/22 12:34
First crash: 2126d, last: 2108d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in deactivate_super 4 246d 295d 0/3 auto-obsoleted due to no activity on 2023/11/26 12:17
linux-4.14 INFO: task hung in deactivate_super 1 1818d 1818d 0/1 auto-closed as invalid on 2019/10/25 08:42
upstream INFO: task hung in deactivate_super exfat 36 1929d 2032d 0/26 closed as dup on 2018/10/27 13:17
upstream INFO: task hung in deactivate_super (2) reiserfs C inconclusive done 121 48d 387d 26/26 fixed on 2024/04/08 19:23
linux-5.15 INFO: task hung in deactivate_super 4 243d 331d 0/3 auto-obsoleted due to no activity on 2023/11/29 20:11
linux-6.1 INFO: task hung in deactivate_super (2) 1 66d 66d 0/3 upstream: reported on 2024/02/14 05:27
linux-4.19 INFO: task hung in deactivate_super 4 420d 521d 0/1 upstream: reported on 2022/11/16 10:48

Sample crash report:
FAT-fs (loop2): Unrecognized mount option "/dev/net/tun" or missing value
INFO: task syz-executor0:21367 blocked for more than 140 seconds.
      Not tainted 4.9.112-g9e79039 #7
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D27016 21367      1 0x00000002
 ffff8801b791b000 0000000000000000 ffff8801aa865a40 ffff8801d9aa3000
 ffff8801db321c18 ffff8801bb2279d8 ffffffff839e907d ffffffff81235667
 0000000000000000 ffff8801b791b8c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ea67f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839f5cb8>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f5cb8>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee7527>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff839f3a8c>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff839f3a8c>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff8157ace9>] deactivate_super+0x89/0xd0 fs/super.c:340
 [<ffffffff815dd032>] cleanup_mnt+0xb2/0x160 fs/namespace.c:1134
 [<ffffffff815dd166>] __cleanup_mnt+0x16/0x20 fs/namespace.c:1141
 [<ffffffff8119839c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff81140eb1>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff81140eb1>] do_exit+0x9e1/0x27c0 kernel/exit.c:837
 [<ffffffff81146fb1>] do_group_exit+0x111/0x340 kernel/exit.c:941
 [<ffffffff811471fd>] SYSC_exit_group kernel/exit.c:952 [inline]
 [<ffffffff811471fd>] SyS_exit_group+0x1d/0x20 kernel/exit.c:950
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9f53>] 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: [<ffffffff8136675c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136675c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425de7>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3779:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f8122>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211edc2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor0/21367:
 #0:  (&type->s_umount_key#38){++++..}, at: [<ffffffff8157ace9>] deactivate_super+0x89/0xd0 fs/super.c:340
1 lock held by syz-executor7/8581:
 #0:  (&type->s_umount_key#38){++++..}, at: [<ffffffff8157cdb1>] iterate_supers+0xe1/0x260 fs/super.c:591

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

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.112-g9e79039 #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d84c7d08 ffffffff81eb3249 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b9bd0 ffff8801d84c7d40
 ffffffff81ebe547 0000000000000000 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81eb3249>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb3249>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebe547>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebe4da>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366cf4>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366cf4>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366cf4>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366cf4>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0bd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fa11c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4861 Comm: kworker/u4:6 Not tainted 4.9.112-g9e79039 #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfnc (flush-7:0)c
task: ffff88019ba78000 task.stack: ffff88019ba80000
RIP: 0010:[<ffffffff8162183d>] c [<ffffffff8162183d>] blkdev_max_block fs/buffer.c:942 [inline]
RIP: 0010:[<ffffffff8162183d>] c [<ffffffff8162183d>] init_page_buffers+0x17d/0x350 fs/buffer.c:957
RSP: 0018:ffff88019ba87650  EFLAGS: 00000293
RAX: 0000000008100000 RBX: 0000000000000009 RCX: 1ffff100397f6f19
RDX: 0000000000000000 RSI: ffffffff81621839 RDI: ffff8801cbfb7aa0
RBP: ffff88019ba87690 R08: ffff88019ba78988 R09: 0000000000000001
R10: 0000000000000000 R11: 1ffff1003374f12c R12: 0000000000000000
R13: ffff8801b9b8f2a0 R14: ffff8801cbfb78c0 R15: 0000000000000100
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bad1d4834 CR3: 00000001c8515000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000008100000c 0000000000000001c ffffffffffffffffc 0000000000000003c
 0000000000000200c ffffea0006294ac0c 0000000000000200c dffffc0000000000c
 ffff88019ba87730c ffffffff81625729c ffff8801d916a248c ffff8801cbfb78c8c
Call Trace:
 [<ffffffff81625729>] grow_dev_page fs/buffer.c:1014 [inline]
 [<ffffffff81625729>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81625729>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81625729>] __getblk_gfp+0x579/0x710 fs/buffer.c:1386
 [<ffffffff81628cdd>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818d68d1>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818d68d1>] fat_clusters_flush+0x111/0x380 fs/fat/misc.c:69
 [<ffffffff818d0862>] fat_write_inode+0xf2/0x170 fs/fat/inode.c:890
 [<ffffffff8160232d>] write_inode fs/fs-writeback.c:1180 [inline]
 [<ffffffff8160232d>] __writeback_single_inode+0x86d/0x1020 fs/fs-writeback.c:1379
 [<ffffffff8160362c>] writeback_sb_inodes+0x4ac/0xe70 fs/fs-writeback.c:1584
 [<ffffffff816040eb>] __writeback_inodes_wb+0xfb/0x1e0 fs/fs-writeback.c:1653
 [<ffffffff81604872>] wb_writeback+0x512/0xbd0 fs/fs-writeback.c:1762
 [<ffffffff8160e1a0>] wb_check_old_data_flush fs/fs-writeback.c:1877 [inline]
 [<ffffffff8160e1a0>] wb_do_writeback fs/fs-writeback.c:1901 [inline]
 [<ffffffff8160e1a0>] wb_workfn+0x850/0xdb0 fs/fs-writeback.c:1930
 [<ffffffff8118d191>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff8118df86>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119d0bd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fa11c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Code: c33 ce8 c58 cd2 cd3 cff c41 c89 cdf cbb c08 c00 c00 c00 ce8 c4b cd2 cd3 cff c41 cd1 cef c83 cc3 c01 c41 c81 cff c00 c01 c00 c00 c77 cec ce8 c37 cd2 cd3 cff c48 c8b c45 cc0 c<89> cd9 c48 cd3 cf8 c48 c89 c45 cd0 c48 cbb c00 c00 c00 c00 c00 cfc cff cdf c4d c89 c

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/13 19:57 https://android.googlesource.com/kernel/common android-4.9 9e7903954483 92a49505 .config console log report ci-android-49-kasan-gce-root
2018/07/03 09:37 https://android.googlesource.com/kernel/common android-4.9 00a0bcbfcfb6 317fc8ea .config console log report ci-android-49-kasan-gce-root
2018/06/25 23:57 https://android.googlesource.com/kernel/common android-4.9 7cecc756ceae 2064fc5c .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.