INFO: task syz-executor:5836 blocked for more than 143 seconds.
Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21224 pid:5836 tgid:5836 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216
__writeback_inodes_sb_nr+0x1f6/0x250 fs/fs-writeback.c:2747
sync_filesystem+0xa3/0x230 fs/sync.c:54
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618
deactivate_locked_super+0xb9/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
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:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f26e0f8fc57
RSP: 002b:00007ffd5715e618 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f26e1010925 RCX: 00007f26e0f8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd5715e6d0
RBP: 00007ffd5715e6d0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd5715f760
R13: 00007f26e1010925 R14: 000000000001a3bb R15: 00007ffd5715f7a0
Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
2 locks held by kworker/u8:1/13:
#0: ffff88802069a948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88802069a948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
1 lock held by khungtaskd/31:
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5599:
#0: ffff8880310550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5836:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
3 locks held by syz-executor/5841:
2 locks held by syz-executor/6388:
1 lock held by syz.7.110/6968:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.7.110/6971:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.8.123/7090:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.9.234/7871:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.3.288/8205:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.0.293/8271:
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807a2400e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
2 locks held by syz.2.298/8317:
4 locks held by dhcpcd-run-hook/8338:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6388 Comm: syz-executor Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4857 [inline]
RIP: 0010:__lock_acquire+0x332/0xd20 kernel/locking/lockdep.c:5190
Code: e5 15 09 d5 09 cd 44 09 f5 41 89 6c c7 20 45 89 44 c7 24 4c 89 7c 24 10 4d 8d 34 c7 81 e5 ff 1f 00 00 48 0f a3 2d ee 7b 06 12 <73> 10 48 69 c5 c8 00 00 00 48 8d 80 30 b3 45 93 eb 40 83 3d 35 0b
RSP: 0018:ffffc9000c176fc8 EFLAGS: 00000003
RAX: 0000000000000000 RBX: ffffffff8e13ee20 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888076d51e00
RBP: 0000000000000007 R08: 0000000000000000 R09: ffffffff81729af5
R10: ffffc9000c177278 R11: fffff5200182ee51 R12: 0000000000020000
R13: 0000000000000000 R14: ffff888076d528f0 R15: ffff888076d528f0
FS: 0000555562111500(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6e130f7368 CR3: 00000000338a6000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
free_unref_folios+0xcd2/0x1570 mm/page_alloc.c:2763
folios_put_refs+0x559/0x640 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:473
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:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc36078d58a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007ffe633881b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fc36078d58a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffe6338820c R08: 0000000000000000 R09: 00007ffe63387f17
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000003e
R13: 00000000000927c0 R14: 000000000003f5d4 R15: 00007ffe63388260