INFO: task syz.0.886:9588 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.886 state:D stack:28296 pid:9588 tgid:9587 ppid:5824 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 bdev_open+0xe0/0xd30 block/bdev.c:945 blkdev_open+0x457/0x600 block/fops.c:701 do_dentry_open+0x953/0x13f0 fs/open.c:965 vfs_open+0x3b/0x340 fs/open.c:1097 do_open fs/namei.c:3975 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 do_sys_openat2+0x121/0x1c0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe14318df10 RSP: 002b:00007fe14405eb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe14318df10 RDX: 0000000000000000 RSI: 00007fe14405ec10 RDI: 00000000ffffff9c RBP: 00007fe14405ec10 R08: 0000000000000000 R09: 002364626e2f7665 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007fe1433e6038 R14: 00007fe1433e5fa0 R15: 00007ffc040d16f8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:2/36: #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90000ac7ba0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90000ac7ba0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 2 locks held by kworker/0:2/935: 2 locks held by kworker/u8:5/1239: #0: ffff8880b883a058 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:646 #1: ffff8880b8824048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by getty/5588: #0: ffff88802fae40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036be2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/6362: #0: ffff8881437f3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz.0.886/9588: #0: ffff8881437f3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz.6.1225/10830: 1 lock held by sed/10856: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 935 Comm: kworker/0:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events free_obj_work RIP: 0010:lockdep_hardirqs_off+0xb4/0x110 kernel/locking/lockdep.c:4495 Code: 0a 00 00 ff c0 41 89 86 c8 0a 00 00 41 89 86 e4 0a 00 00 eb 17 48 c7 c7 47 c9 75 8d e8 f5 17 00 00 65 8b 05 fe 2b 28 07 85 c0 <74> 80 65 48 8b 05 a2 eb 27 07 48 3b 44 24 08 75 3c 48 83 c4 10 5b RSP: 0018:ffffc900036678b0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff8225ca4d RCX: 01b4841376e85c00 RDX: ffff8880586b2738 RSI: ffffffff8d75c947 RDI: ffffffff8bbf0760 RBP: 0000000000000000 R08: 000000003b2205f7 R09: 00000000c06937ec R10: 000000000000000a R11: ffffffff81ac2f50 R12: ffffea000161ac80 R13: 0000000000000000 R14: ffff88801a0308c0 R15: 0000000000000282 FS: 0000000000000000(0000) GS:ffff88812613b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000034a030 CR3: 000000004022b000 CR4: 0000000000350ef0 Call Trace: trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104 kasan_quarantine_put+0x3d/0x220 mm/kasan/quarantine.c:207 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2539 [inline] slab_free mm/slub.c:6630 [inline] kmem_cache_free+0x19b/0x690 mm/slub.c:6740 free_object_list lib/debugobjects.c:326 [inline] free_obj_work+0x377/0x4a0 lib/debugobjects.c:513 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245