INFO: task syz-executor:5842 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-next-20250718-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21608 pid:5842 tgid:5842 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
kthread_stop+0x194/0x5c0 kernel/kthread.c:790
bch2_copygc_stop+0x4b/0x120 fs/bcachefs/movinggc.c:436
__bch2_fs_read_only+0x4a/0x4f0 fs/bcachefs/super.c:303
bch2_fs_read_only+0x403/0xa40 fs/bcachefs/super.c:389
__bch2_fs_stop+0xc9/0x8f0 fs/bcachefs/super.c:700
generic_shutdown_super+0x132/0x2c0 fs/super.c:643
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2586
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f69ccd8fcd7
RSP: 002b:00007ffd8bb7c198 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f69cce10b55 RCX: 00007f69ccd8fcd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd8bb7c250
RBP: 00007ffd8bb7c250 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd8bb7d2e0
R13: 00007f69cce10b55 R14: 000000000002055a R15: 00007ffd8bb7d320
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5602:
#0: ffff888033e0f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5842:
#0: ffff8880606100e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880606100e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880606100e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888052180278 (&c->state_lock){++++}-{4:4}, at: class_rwsem_write_constructor include/linux/rwsem.h:257 [inline]
#1: ffff888052180278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xc1/0x8f0 fs/bcachefs/super.c:699
3 locks held by udevd/5999:
1 lock held by udevd/6011:
2 locks held by bch-copygc/loop/6730:
#0: ffff8880521843a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffff8880521843a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffff8880521843a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3293
#1: ffff8880521a6710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x53f/0x1e00 fs/bcachefs/btree_update_interior.c:1196
5 locks held by kworker/u8:14/8915:
2 locks held by kworker/u8:26/8929:
2 locks held by syz.0.1051/10224:
#0: ffff888026bae0e0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
#1: ffffffff8dfe4708 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5179 [inline]
#1: ffffffff8dfe4708 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70 kernel/workqueue.c:5734
2 locks held by fido_id/10232:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6011 Comm: udevd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__lock_acquire+0x11/0xd20 kernel/locking/lockdep.c:5085
Code: 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 48 89 fb <65> 48 8b 3c 25 08 d0 a3 92 45 31 ff 83 3d 6c 71 05 0e 00 0f 84 7e
RSP: 0018:ffffc9000ac7f7d0 EFLAGS: 00000082
RAX: 0000000000000001 RBX: ffffffff8de168d0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8de168d0
RBP: ffffffff823cae38 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100b1d1d32 R12: 0000000000000000
R13: ffffffff8de168d0 R14: 0000000000000001 R15: 0000000000000246
FS: 00007fdf68bf0880(0000) GS:ffff888125ce3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dbed8635f8 CR3: 0000000077906000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
mnt_get_write_access+0x85/0x2a0 fs/namespace.c:508
mnt_want_write+0x49/0x90 fs/namespace.c:558
do_open fs/namei.c:3880 [inline]
path_openat+0x2d4b/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdf684a7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fffd2a0e9a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fdf68bf0880 RCX: 00007fdf684a7407
RDX: 00000000000a0241 RSI: 00007fffd2a0f660 RDI: ffffffffffffff9c
RBP: 0000563cfacbb8a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000124 R11: 0000000000000202 R12: 0000563cfab97bd0
R13: 00007fffd2a0f660 R14: 00007fffd2a0f260 R15: 00007fffd2a0ee60