INFO: task syz.6.2605:12924 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.2605 state:D stack:26896 pid:12924 ppid:11971 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747 sync_bdevs+0x1a4/0x320 block/bdev.c:1077 ksys_sync+0xc6/0x170 fs/sync.c:105 ksys_sync_helper+0x17/0xa0 kernel/power/main.c:91 enter_state kernel/power/suspend.c:583 [inline] pm_suspend+0x1b8/0x950 kernel/power/suspend.c:626 state_store+0x206/0x290 kernel/power/main.c:708 kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f879079de99 RSP: 002b:00007f8791717028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8790a25fa0 RCX: 00007f879079de99 RDX: 0000000000000006 RSI: 0000200000000240 RDI: 0000000000000003 RBP: 00007f8790833eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8790a26038 R14: 00007f8790a25fa0 R15: 00007ffdf038b9f8 Showing all locks held in the system: 2 locks held by rcu_tasks_trace/15: #0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559 #1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6696 1 lock held by khungtaskd/28: #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/u4:5/155: 3 locks held by kworker/u4:6/161: #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc90002f37d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc90002f37d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 2 locks held by getty/5532: #0: ffff88814c8da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 1 lock held by udevd/5768: #0: ffff888021ec24c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801 2 locks held by kworker/1:1/11264: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc9000d2afd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000d2afd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 6 locks held by syz.6.2605/12924: #0: ffff8880788654c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888030460418 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffff88802e065888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x520 fs/kernfs/file.c:343 #3: ffff8881422669b8 (kn->active#99){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #3: ffff8881422669b8 (kn->active#99){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344 #4: ffffffff8cfe58a8 (system_transition_mutex){+.+.}-{3:3}, at: enter_state kernel/power/suspend.c:575 [inline] #4: ffffffff8cfe58a8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x120/0x950 kernel/power/suspend.c:626 #5: ffff888021ec24c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1a4/0x320 block/bdev.c:1077 1 lock held by syz-executor/13200: #0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 1 lock held by dhcpcd/15889: #0: ffff8880270f8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline] #0: ffff8880270f8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3264 1 lock held by dhcpcd-run-hook/15891: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf59/0xfa0 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 13200 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:get_dep_list kernel/locking/lockdep.c:1554 [inline] RIP: 0010:__bfs_next kernel/locking/lockdep.c:1686 [inline] RIP: 0010:__bfs kernel/locking/lockdep.c:1736 [inline] RIP: 0010:__bfs_forwards kernel/locking/lockdep.c:1832 [inline] RIP: 0010:find_usage_forwards+0xd7/0x6e0 kernel/locking/lockdep.c:2321 Code: 4c 89 e7 e8 9b 7f 76 00 4d 8b 24 24 4d 85 e4 74 4d 49 83 c4 10 4c 89 e0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 e7 e8 79 7f 76 00 <4d> 8b 34 24 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 60 RSP: 0018:ffffc9000b46eda0 EFLAGS: 00000046 RAX: 1ffffffff279590a RBX: dffffc0000000000 RCX: 000000000000000b RDX: ffffc9000b46ef18 RSI: 00000000000000cc RDI: ffffffff93d6db60 RBP: 1ffffffff216aae1 R08: ffffffff911eb507 R09: 1ffffffff223d6a0 R10: dffffc0000000000 R11: fffffbfff223d6a1 R12: ffffffff93cac850 R13: ffffffff90b5570c R14: 0000000000044e0f R15: ffffffff93b061c0 FS: 000055555aea5500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056171ab7f078 CR3: 0000000040b9c000 CR4: 00000000003506e0 Call Trace: check_irq_usage kernel/locking/lockdep.c:2822 [inline] check_prev_add kernel/locking/lockdep.c:3138 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x46d1/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 _raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559 raw_spin_rq_lock kernel/sched/sched.h:1379 [inline] rq_lock kernel/sched/sched.h:1688 [inline] ttwu_queue kernel/sched/core.c:4026 [inline] try_to_wake_up+0x58d/0x10e0 kernel/sched/core.c:4349 kick_pool+0x320/0x420 kernel/workqueue.c:1165 __queue_work+0xc05/0xfd0 kernel/workqueue.c:1820 mod_delayed_work_on+0xc7/0x1c0 kernel/workqueue.c:2044 kblockd_mod_delayed_work_on+0x29/0x40 block/blk-core.c:1075 blk_insert_flush+0x3c4/0x4e0 block/blk-flush.c:464 blk_mq_submit_bio+0xdc5/0x2220 block/blk-mq.c:3078 __submit_bio+0x12b/0x260 block/blk-core.c:610 __submit_bio_noacct_mq block/blk-core.c:689 [inline] submit_bio_noacct_nocheck+0x6e8/0x9c0 block/blk-core.c:718 __submit_merged_bio+0x258/0x630 fs/f2fs/data.c:545 __f2fs_submit_merged_write fs/f2fs/data.c:638 [inline] __submit_merged_write_cond+0x245/0x500 fs/f2fs/data.c:660 commit_checkpoint fs/f2fs/checkpoint.c:1436 [inline] do_checkpoint+0x22eb/0x3b30 fs/f2fs/checkpoint.c:1584 f2fs_write_checkpoint+0x177a/0x1f70 fs/f2fs/checkpoint.c:1698 kill_f2fs_super+0x26f/0x3f0 fs/f2fs/super.c:4893 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f492859f0d7 Code: a2 c7 05 1c 26 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd1e0d2a68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f492863330a RCX: 00007f492859f0d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd1e0d2b20 RBP: 00007ffd1e0d2b20 R08: 00007ffd1e0d3b20 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1e0d3bb0 R13: 00007f492863330a R14: 000000000009ec41 R15: 00007ffd1e0d3bf0