INFO: task kworker/u8:2:36 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:21576 pid:36    tgid:36    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
 <TASK>
 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
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 __mutex_lock_common kernel/locking/mutex.c:678 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746
 jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:132
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x6ee/0xff0 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x6b5/0x1000 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
 wb_do_writeback fs/fs-writeback.c:2315 [inline]
 wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
 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
 </TASK>

Showing all locks held in the system:
2 locks held by ksoftirqd/0/15:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/u8:2/36:
 #0: ffff888144292148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff888144292148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
 #1: ffffc90000ad7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90000ad7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
 #2: ffff8880333660e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
 #3: ffff88807ab3b918 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
3 locks held by kworker/u8:4/63:
 #0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: call_timer_fn+0xbe/0x5f0 kernel/time/timer.c:1786
 #1: ffffc9000155fc60 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000155fc60 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_worker+0xd2/0x610 net/batman-adv/network-coding.c:719
2 locks held by getty/5575:
 #0: ffff88803074d0a0 (&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
4 locks held by syz.2.136/6942:
1 lock held by syz-executor/7456:
 #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
4 locks held by syz.1.419/9609:
1 lock held by syz.5.422/9619:
 #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz.3.425/9628:
1 lock held by dhcpcd-run-hook/9638:
 #0: ffff88807fbd4068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_read+0xd14/0x1040 fs/pipe.c:393
1 lock held by dhcpcd-run-hook/9668:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9638 Comm: dhcpcd-run-hook Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__unwind_start+0x3f9/0x760 arch/x86/kernel/unwind_orc.c:727
Code: 4c 89 e0 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 53 03 00 00 41 88 2c 24 40 b5 01 4c 8d 63 38 4c 89 e0 48 c1 e8 03 48 89 44 24 08 <80> 3c 10 00 74 12 4c 89 e7 e8 a9 ca ad 00 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc90004a47868 EFLAGS: 00000a02
RAX: 1ffff92000948f20 RBX: ffffc90004a478c8 RCX: ffffc90004a47868
RDX: dffffc0000000000 RSI: ffffffff8171f2a8 RDI: ffffc90004a47928
RBP: ffffc90004a47901 R08: ffffc90004a47927 R09: 0000000000000000
R10: ffffc90004a478c8 R11: fffff52000948f25 R12: ffffc90004a47900
R13: ffffc90004a47908 R14: ffffc90004a478f0 R15: 1ffff92000948f1e
FS:  00007fbaed5c7c80(0000) GS:ffff8881260fb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe3bc81108 CR3: 000000004d91a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 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
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203
 lsm_inode_alloc security/security.c:755 [inline]
 security_inode_alloc+0x39/0x330 security/security.c:1697
 inode_init_always_gfp+0x9ed/0xdc0 fs/inode.c:306
 inode_init_always include/linux/fs.h:3226 [inline]
 alloc_inode+0x82/0x1b0 fs/inode.c:353
 new_inode_pseudo include/linux/fs.h:3309 [inline]
 get_pipe_inode fs/pipe.c:887 [inline]
 create_pipe_files+0x51/0x760 fs/pipe.c:927
 __do_pipe_flags+0x4c/0x2d0 fs/pipe.c:984
 do_pipe2+0x9c/0x170 fs/pipe.c:1035
 __do_sys_pipe2 fs/pipe.c:1053 [inline]
 __se_sys_pipe2 fs/pipe.c:1051 [inline]
 __x64_sys_pipe2+0x5a/0x70 fs/pipe.c:1051
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbaed784ec9
Code: 07 31 c0 e9 49 ff ff ff 50 48 8d 3d a9 3a 0a 00 e8 ec 64 01 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 31 f6 b8 25 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 07 c3 66 0f 1f 44 00 00 48 8b 15 f9 be 0d 00
RSP: 002b:00007ffe3bc80dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000125
RAX: ffffffffffffffda RBX: 00005568a8ca9290 RCX: 00007fbaed784ec9
RDX: 00005568a8c9bc30 RSI: 0000000000000000 RDI: 00007ffe3bc80e30
RBP: 00005568a8c9bc30 R08: 0000000000000001 R09: 0000000000000030
R10: 0000000000000050 R11: 0000000000000246 R12: 0000000000000084
R13: 00005568a8c9bc30 R14: 0000000000000001 R15: 0000000000000000
 </TASK>