syzbot


INFO: task hung in do_journal_end

Status: upstream: reported syz repro on 2025/06/12 14:55
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+78cf9bfb5988cce636a8@syzkaller.appspotmail.com
First crash: 19d, last: 19d
Bug presence (2)
Date Name Commit Repro Result
2025/06/15 linux-6.1.y (ToT) 58485ff1a74f C [report] INFO: task hung in flush_old_commits
2025/06/15 upstream (ToT) 8c6bc74c7f89 C Didn't crash
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_journal_end reiserfs 1 887d 887d 0/29 auto-obsoleted due to no activity on 2023/04/27 08:10

Sample crash report:
INFO: task syz.1.1566:9637 blocked for more than 143 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1566      state:D stack:0     pid:9637  ppid:4461   flags:0x0000000d
Call trace:
 __switch_to+0x2f4/0x568 arch/arm64/kernel/process.c:555
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0xdd4/0x1b2c kernel/sched/core.c:6561
 schedule+0xc4/0x170 kernel/sched/core.c:6637
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6696
 __mutex_lock_common+0xad4/0x1f38 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
 reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:815 [inline]
 lock_journal fs/reiserfs/journal.c:534 [inline]
 do_journal_end+0x2fc/0x3bb0 fs/reiserfs/journal.c:4029
 journal_end+0x1cc/0x270 fs/reiserfs/journal.c:3418
 reiserfs_do_truncate+0x970/0x1020 fs/reiserfs/stree.c:2013
 reiserfs_truncate_file+0x5c0/0xaf4 fs/reiserfs/inode.c:2310
 reiserfs_file_release+0x710/0x894 fs/reiserfs/file.c:109
 __fput+0x1bc/0x7c0 fs/file_table.c:320
 ____fput+0x20/0x30 fs/file_table.c:348
 task_work_run+0x1ec/0x270 kernel/task_work.c:203
 get_signal+0x1120/0x1310 kernel/signal.c:2648
 do_signal arch/arm64/kernel/signal.c:1081 [inline]
 do_notify_resume+0x340/0x2b0c arch/arm64/kernel/signal.c:1134
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz.1.1566:9650 blocked for more than 143 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1566      state:D stack:0     pid:9650  ppid:4461   flags:0x00000009
Call trace:
 __switch_to+0x2f4/0x568 arch/arm64/kernel/process.c:555
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0xdd4/0x1b2c kernel/sched/core.c:6561
 schedule+0xc4/0x170 kernel/sched/core.c:6637
 io_schedule+0x84/0x154 kernel/sched/core.c:8797
 folio_wait_bit_common+0x56c/0x9c4 mm/filemap.c:1324
 __folio_lock mm/filemap.c:1687 [inline]
 folio_lock include/linux/pagemap.h:974 [inline]
 __filemap_get_folio+0x4ec/0xab0 mm/filemap.c:1959
 pagecache_get_page+0x3c/0x16c mm/folio-compat.c:110
 find_or_create_page include/linux/pagemap.h:646 [inline]
 grab_cache_page include/linux/pagemap.h:778 [inline]
 convert_tail_for_hole fs/reiserfs/inode.c:592 [inline]
 reiserfs_get_block+0x2248/0x3524 fs/reiserfs/inode.c:921
 __block_write_begin_int+0x34c/0x13b8 fs/buffer.c:1991
 __block_write_begin+0x7c/0xa0 fs/buffer.c:2041
 reiserfs_write_begin+0x328/0x71c fs/reiserfs/inode.c:2775
 generic_cont_expand_simple+0x12c/0x1fc fs/buffer.c:2347
 reiserfs_setattr+0x564/0xf7c fs/reiserfs/inode.c:3305
 notify_change+0xb0c/0xdcc fs/attr.c:499
 do_truncate+0x178/0x1f0 fs/open.c:65
 vfs_truncate+0x23c/0x2b0 fs/open.c:111
 do_sys_truncate+0xe8/0x1b0 fs/open.c:134
 __do_sys_truncate fs/open.c:146 [inline]
 __se_sys_truncate fs/open.c:144 [inline]
 __arm64_sys_truncate+0x5c/0x70 fs/open.c:144
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015247670 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xbb4 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffff800015247e90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xbb4 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffff800015246d00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
2 locks held by kworker/0:2/112:
 #0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265
 #1: ffff800020427c20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267
4 locks held by kworker/1:3/3874:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265
 #1: ffff8000233e7c20 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267
 #2: ffff0000d311c0e0 (&type->s_umount_key#50){++++}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000eaa40090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by getty/4063:
 #0: ffff0000d674a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80001ce702f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2ec/0xf9c drivers/tty/n_tty.c:2198
1 lock held by udevd/4394:
4 locks held by kworker/1:8/4440:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265
 #1: ffff800020c97c20 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267
 #2: ffff0000d970a0e0 (&type->s_umount_key#50){++++}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000dc1d7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
3 locks held by kworker/1:9/4441:
 #0: ffff00019f74c158 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline]
 #0: ffff00019f74c158 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1355 [inline]
 #0: ffff00019f74c158 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1645 [inline]
 #0: ffff00019f74c158 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2b8/0x1b2c kernel/sched/core.c:6477
 #1: ffff00019f738b88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x380/0x608 kernel/sched/psi.c:999
 #2: ffff800015246d60 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349
4 locks held by kworker/0:6/4449:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265
 #1: ffff800020d07c20 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267
 #2: ffff0000df1f60e0 (&type->s_umount_key#50){++++}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d0533090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
1 lock held by syz-executor/4467:
 #0: ffff80001524c9b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #0: ffff80001524c9b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a8/0x6f0 kernel/rcu/tree_exp.h:962
2 locks held by udevd/4537:
3 locks held by kworker/u4:9/4785:
3 locks held by syz.1.1566/9637:
 #0: ffff0000e962eab8 (&ei->tailpack){+.+.}-{3:3}, at: reiserfs_file_release+0xc8/0x894 fs/reiserfs/file.c:41
 #1: ffff8000211ab0f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 #1: ffff8000211ab0f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline]
 #1: ffff8000211ab0f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_end+0x2f0/0x3bb0 fs/reiserfs/journal.c:4029
 #2: ffff0000d0533090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
3 locks held by syz.1.1566/9650:
 #0: ffff0000df1f6460 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #1: ffff0000e962ece0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff0000e962ece0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x164/0x1f0 fs/open.c:63
 #2: ffff0000d0533090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
3 locks held by syz.2.1865/10630:
 #0: ffff0000e9660758 (&ei->tailpack){+.+.}-{3:3}, at: reiserfs_file_release+0xc8/0x894 fs/reiserfs/file.c:41
 #1: ffff8000218f90f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 #1: ffff8000218f90f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline]
 #1: ffff8000218f90f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_end+0x2f0/0x3bb0 fs/reiserfs/journal.c:4029
 #2: ffff0000eaa40090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
3 locks held by syz.2.1865/10644:
 #0: ffff0000d311c460 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #1: ffff0000e9660980 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff0000e9660980 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x164/0x1f0 fs/open.c:63
 #2: ffff0000eaa40090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
1 lock held by syz-executor/10896:
 #0: ffff0000dd9f40e0 (&type->s_umount_key#50){++++}-{3:3}, at: deactivate_super+0xe0/0x108 fs/super.c:362
1 lock held by udevd/11075:
3 locks held by syz.0.2154/11565:
 #0: ffff0000e962dd78 (&ei->tailpack){+.+.}-{3:3}, at: reiserfs_file_release+0xc8/0x894 fs/reiserfs/file.c:41
 #1: ffff800021b2c0f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 #1: ffff800021b2c0f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline]
 #1: ffff800021b2c0f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_end+0x2f0/0x3bb0 fs/reiserfs/journal.c:4029
 #2: ffff0000dc1d7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
3 locks held by syz.0.2154/11579:
 #0: ffff0000d970a460 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #1: ffff0000e962dfa0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff0000e962dfa0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x164/0x1f0 fs/open.c:63
 #2: ffff0000dc1d7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78
1 lock held by syz-executor/11836:
 #0: ffff0000cb9fc0e0 (&type->s_umount_key#50){++++}-{3:3}, at: deactivate_super+0xe0/0x108 fs/super.c:362
2 locks held by syz.5.2397/12374:
1 lock held by syz.3.2399/12378:

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


Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/12 23:15 linux-6.1.y 58485ff1a74f 98683f8f .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 INFO: task hung in do_journal_end
2025/06/12 14:54 linux-6.1.y 58485ff1a74f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in do_journal_end
* Struck through repros no longer work on HEAD.