INFO: task kworker/1:0:24 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:24808 pid:24 tgid:24 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events p9_write_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760 anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 __kernel_write_iter+0x317/0xb10 fs/read_write.c:619 __kernel_write fs/read_write.c:639 [inline] kernel_write fs/read_write.c:660 [inline] kernel_write+0x1f4/0x6c0 fs/read_write.c:650 p9_fd_write net/9p/trans_fd.c:434 [inline] p9_write_work+0x258/0xc10 net/9p/trans_fd.c:485 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/0:0/9: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900000e7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff888063768068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 3 locks held by kworker/1:0/24: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900001e7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88807b6f6468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 1 lock held by khungtaskd/31: #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/36: #0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 #1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline] #1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6955 #2: ffff8880295b8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6212 [inline] #2: ffff8880295b8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x99/0x580 net/wireless/core.c:421 5 locks held by kworker/u8:3/37: #0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 #1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline] #1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6955 #2: ffff8880b8425b18 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x127/0x1d0 kernel/time/timer.c:1004 #3: ffffffff9b089b08 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x14c/0x4c0 lib/debugobjects.c:818 #4: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #4: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #4: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] #4: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479 3 locks held by kworker/1:2/978: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90003967d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88802ead4068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 3 locks held by klogd/5210: #0: ffff8880b853a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 #1: ffffffff8e781e40 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 #2: ffff88806a72d2a8 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] #2: ffff88806a72d2a8 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb7/0x1870 kernel/sched/core.c:4216 2 locks held by getty/5611: #0: ffff88803604e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:3/5886: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000237fd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88806939a068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 3 locks held by kworker/0:4/5893: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900041dfd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88803528a868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 3 locks held by kworker/1:3/5993: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900032c7d10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88806979f468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 2 locks held by syz.0.16/6470: #0: ffff88807b6f6468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e02e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e02e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 2 locks held by syz.1.18/6497: #0: ffff88806939a068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e0958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e0958 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 2 locks held by syz.2.19/6520: #0: ffff88803528a868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e0fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e0fc8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 3 locks held by kworker/1:5/6521: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000213fd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff888077d0f068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 2 locks held by syz.3.20/6550: #0: ffff88806979f468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e1638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e1638 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 3 locks held by kworker/1:6/6552: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90003d5fd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff8880332aac68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 2 locks held by syz.4.21/6581: #0: ffff8880332aac68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e1ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e1ca8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 2 locks held by syz.5.22/6611: #0: ffff888063768068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880772502e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880772502e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 3 locks held by kworker/0:7/6639: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900042bfd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff888060bafc68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 2 locks held by syz.6.23/6641: #0: ffff888060bafc68 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e2318 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e2318 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 2 locks held by syz.7.24/6676: #0: ffff888077d0f068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e2988 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e2988 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 3 locks held by kworker/1:8/6678: #0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900044afd10 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff888027d63068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 2 locks held by syz.8.25/6708: #0: ffff88802ead4068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e2ff8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e2ff8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 2 locks held by syz.9.26/6738: #0: ffff888027d63068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1a90 fs/pipe.c:458 #1: ffff8880789e3668 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline] #1: ffff8880789e3668 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_fault+0x61d/0x2930 mm/filemap.c:3452 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/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+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 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: 2954 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:register_lock_class+0x7b/0x4c0 kernel/locking/lockdep.c:1394 Code: 11 83 e5 01 75 0c 41 83 fe 01 75 0a 4c 89 7b 10 eb 04 4c 89 7b 08 8b 15 53 14 4e 19 85 d2 75 0a 45 39 77 58 0f 85 ef 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c0 a3 3e 12 0f 85 1f 04 00 00 48 83 c4 RSP: 0018:ffffc9000bd07aa8 EFLAGS: 00000046 RAX: ffffffff95e36768 RBX: ffffc9000bd07d10 RCX: ffffffff8d116d60 RDX: 0000000000000000 RSI: ffffffff8d116d60 RDI: ffffc9000bd07d10 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 000000009b30bc01 R13: ffff888030a3c880 R14: 0000000000000000 R15: ffffffff95e36768 FS: 0000000000000000(0000) GS:ffff8881247b9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556f5165c8 CR3: 0000000034834000 CR4: 00000000003526f0 Call Trace: __lock_acquire+0x9f/0x1ce0 kernel/locking/lockdep.c:5112 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 process_one_work+0x932/0x1b70 kernel/workqueue.c:3212 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245