INFO: task syz-executor:5846 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:18856 pid:5846 tgid:5846 ppid:1 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
__bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:696
generic_shutdown_super+0x135/0x2c0 fs/super.c:643
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:1375
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:225 [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: 0033:0x7f4e623eff57
RSP: 002b:00007fff995b6758 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f4e623eff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff995b6810
RBP: 00007fff995b6810 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff995b78a0
R13: 00007f4e62471c2d R14: 000000000003995b R15: 00007fff995b78e0
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:7/1159:
4 locks held by kworker/u8:8/1169:
#0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90004e2fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90004e2fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecc6940 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658
#3: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12719
1 lock held by dhcpcd/5499:
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
2 locks held by getty/5593:
#0: ffff88823bf8e8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5846:
#0: ffff8880213d20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880213d20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880213d20d0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
1 lock held by syz-executor/5847:
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3433
3 locks held by kworker/u8:11/5986:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000538fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000538fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by syz-executor/8034:
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8ecd3838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
2 locks held by syz.5.269/8343:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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+0x436/0x7d0 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: 8348 Comm: syz.6.270 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
RIP: 0010:lock_release+0xb0/0x3e0 kernel/locking/lockdep.c:5888
Code: 00 00 00 0f 85 1e 02 00 00 49 81 3e 00 f3 b9 92 0f 84 11 02 00 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 48 8b 5c 24 20 fa <48> c7 c7 5e e0 04 8d e8 c4 17 5b 09 65 ff 05 2d 6c 5a 10 c7 44 24
RSP: 0000:ffffc90008397a18 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0bff1b6864b7c700
RDX: 0000000000000001 RSI: ffffffff8b621660 RDI: ffffffff8b621620
RBP: ffffc90008397b10 R08: ffff88803166f057 R09: 1ffff110062cde0a
R10: dffffc0000000000 R11: ffffed10062cde0b R12: dffffc0000000000
R13: ffffffff8af95bf7 R14: ffff88803166f018 R15: ffff88801cb30000
FS: 00007f03107e66c0(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0308464000 CR3: 000000005238c000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x70/0x110 kernel/locking/spinlock.c:194
raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:94 [inline]
rtlock_slowlock kernel/locking/rtmutex.c:1896 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x167/0x2c0 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:44 [inline]
__pte_offset_map_lock+0x13e/0x210 mm/pgtable-generic.c:401
pte_offset_map_lock include/linux/mm.h:3029 [inline]
do_anonymous_page mm/memory.c:5030 [inline]
do_pte_missing mm/memory.c:4232 [inline]
handle_pte_fault mm/memory.c:6052 [inline]
__handle_mm_fault mm/memory.c:6195 [inline]
handle_mm_fault+0x17d5/0x3400 mm/memory.c:6364
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f0312440ca6
Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01
RSP: 002b:00007f03107e54a0 EFLAGS: 00010206
RAX: 000000000009e001 RBX: 00007f03107e5540 RCX: 00000000000000c2
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f03107e55e0
RBP: 0000000000000102 R08: 00007f03083c6000 R09: 000000000009e000
R10: 0000000000000000 R11: 00007f03107e5550 R12: 0000000000000001
R13: 00007f031261da20 R14: 0000000000000000 R15: 00007f03107e55e0