INFO: task syz-executor:16315 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22232 pid:16315 tgid:16315 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
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:621
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2620
deactivate_locked_super+0xb9/0x130 fs/super.c:473
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1435
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feee8b8fc97
RSP: 002b:00007ffdb2e3ffb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007feee8c1089d RCX: 00007feee8b8fc97
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdb2e40070
RBP: 00007ffdb2e40070 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdb2e41100
R13: 00007feee8c1089d R14: 00000000000cd1e7 R15: 00007ffdb2e41140
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5579:
#0: ffff8880344c20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by kworker/u8:8/5886:
#0: ffff88801fa83148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801fa83148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000438fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000438fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
1 lock held by syz-executor/16315:
#0: ffff88805cf020e0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88805cf020e0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88805cf020e0 (&type->s_umount_key#89){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
1 lock held by syz-executor/18588:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.4.1531/19523:
#0: ffff88805cf020e0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88805cf020e0 (&type->s_umount_key#89){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120
1 lock held by syz.7.1556/19750:
3 locks held by syz.5.1555/19764:
1 lock held by dhcpcd-run-hook/19770:
#0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 2989 Comm: kworker/u8:7 Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0xa2/0xd20 kernel/locking/lockdep.c:5136
Code: 89 d5 e8 31 f0 ff ff 45 89 ea 45 89 f1 48 8b 3c 24 48 85 c0 0f 84 5c 0a 00 00 8b 8f e8 0a 00 00 83 3d c1 05 df 17 00 0f 94 c2 <83> f9 30 40 0f 93 c6 40 20 d6 40 80 fe 01 0f 84 fa 00 00 00 44 8b
RSP: 0018:ffffc9000b4479a0 EFLAGS: 00000046
RAX: ffffffff931a9c58 RBX: ffffffff8df3b860 RCX: 0000000000000002
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88802fc43c00
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8b1cf532 R12: 0000000000000000
R13: ffffffff8df3b860 R14: 0000000000000000 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561b6c0c2950 CR3: 0000000060128000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245