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INFO: task hung in bch2_rebalance_stop (3)

Status: auto-obsoleted due to no activity on 2025/11/25 22:57
Subsystems: kernel
[Documentation on labels]
First crash: 155d, last: 155d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in bch2_rebalance_stop (2) kernel 1 1 367d 367d 0/29 auto-obsoleted due to no activity on 2025/04/28 01:42
upstream INFO: task hung in bch2_rebalance_stop fs 1 17 536d 602d 0/29 auto-obsoleted due to no activity on 2024/10/07 10:10

Sample crash report:
INFO: task kworker/0:0:9 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0     state:D stack:0     pid:9     tgid:9     ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: events_long bch2_fs_read_only_work
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7058
 schedule_timeout+0xac/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x288/0x3f8 kernel/sched/completion.c:100
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x44/0x5c kernel/sched/completion.c:153
 kthread_stop+0x1bc/0x724 kernel/kthread.c:790
 bch2_rebalance_stop+0xb0/0x17c fs/bcachefs/rebalance.c:709
 __bch2_fs_read_only+0x5c/0x4dc fs/bcachefs/super.c:279
 bch2_fs_read_only+0x344/0x960 fs/bcachefs/super.c:366
 bch2_fs_read_only_work+0x30/0x48 fs/bcachefs/super.c:409
 process_one_work+0x7e8/0x155c kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
INFO: task kworker/u9:0:52 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:0    state:D stack:0     pid:52    tgid:52    ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: bcachefs bch2_write_point_do_index_updates
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7058
 bch2_btree_update_start+0x10f8/0x1ab8 fs/bcachefs/btree_update_interior.c:1179
 bch2_btree_split_leaf+0x118/0x71c fs/bcachefs/btree_update_interior.c:1921
 bch2_trans_commit_error+0x17c/0x11a0 fs/bcachefs/btree_trans_commit.c:914
 __bch2_trans_commit+0x17a4/0x625c fs/bcachefs/btree_trans_commit.c:1104
 bch2_trans_commit fs/bcachefs/btree_update.h:241 [inline]
 __bch2_data_update_index_update+0x3684/0x3ff8 fs/bcachefs/data_update.c:456
 bch2_data_update_index_update+0x6c/0xa8 fs/bcachefs/data_update.c:502
 __bch2_write_index+0x818/0xfa8 fs/bcachefs/io_write.c:607
 bch2_write_point_do_index_updates+0x3cc/0x4f0 fs/bcachefs/io_write.c:718
 process_one_work+0x7e8/0x155c kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
INFO: task bch-rebalance/l:7176 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:bch-rebalance/l state:D stack:0     pid:7176  tgid:7176  ppid:2      task_flags:0x200040 flags:0x00000090
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7058
 bch2_move_ratelimit+0x990/0xf08 fs/bcachefs/move.c:585
 do_rebalance+0xd6c/0x1110 fs/bcachefs/rebalance.c:557
 bch2_rebalance_thread+0x2b4/0x37c fs/bcachefs/rebalance.c:626
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844

Showing all locks held in the system:
3 locks held by kworker/0:0/9:
 #0: ffff0000c0029948 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210
 #1: ffff800097be7bc0 ((work_completion)(&c->read_only_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210
 #2: ffff000101600278 (&c->state_lock){++++}-{4:4}, at: bch2_fs_read_only_work+0x28/0x48 fs/bcachefs/super.c:408
1 lock held by khungtaskd/32:
 #0: ffff80008f9a9060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
1 lock held by pr/ttyAMA-1/43:
3 locks held by kworker/u9:0/52:
 #0: ffff0000dc511948 ((wq_completion)bcachefs){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210
 #1: ffff800099327bc0 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210
 #2: ffff000101604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:160
2 locks held by klogd/6159:
2 locks held by getty/6317:
 #0: ffff0000d2d760a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000993a42f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/6553:
 #0: ffff0000d9efe0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff0000d9efe0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff0000d9efe0e0 (&type->s_umount_key#62){++++}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506
 #1: ffff000101600278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xfc/0x800 fs/bcachefs/super.c:676

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


Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/27 22:49 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f5ae30d69d7 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in bch2_rebalance_stop
* Struck through repros no longer work on HEAD.