INFO: task syz.0.497:8795 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.497 state:D stack:28904 pid:8795 tgid:8792 ppid:5862 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7118 __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 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1059 setup_bdev_super+0x5a/0x5b0 fs/super.c:1609 get_tree_bdev_flags+0x366/0x4d0 fs/super.c:1689 vfs_get_tree+0x92/0x2b0 fs/super.c:1751 fc_mount fs/namespace.c:1274 [inline] do_new_mount_fc fs/namespace.c:3726 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3802 do_mount fs/namespace.c:4125 [inline] __do_sys_mount fs/namespace.c:4324 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4301 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: 0033:0x7fd4dfb8eba9 RSP: 002b:00007fd4e0938038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd4dfdd6180 RCX: 00007fd4dfb8eba9 RDX: 0000200000000080 RSI: 0000200000000040 RDI: 00002000000000c0 RBP: 00007fd4dfc11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd4dfdd6218 R14: 00007fd4dfdd6180 R15: 00007ffdf80b4188 Showing all locks held in the system: 2 locks held by kworker/u8:0/12: #0: ffff88801eb81148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801eb81148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90000117ba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90000117ba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 1 lock held by khungtaskd/31: #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5627: #0: ffff88814d52a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5870: #0: ffff888025730358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 2 locks held by udevd/5879: 3 locks held by kworker/1:6/5987: 2 locks held by kworker/u8:16/8556: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:644 #1: ffff8880b8624008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by syz.0.497/8795: #0: ffff88802a0fc0e0 (&type->s_umount_key#127/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x930 fs/super.c:344 #1: ffff888025730358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by rm/11168: ============================================= 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 08/18/2025 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11170 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline] RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] RIP: 0010:_raw_spin_lock_irqsave+0x73/0xf0 kernel/locking/spinlock.c:162 Code: b8 f1 f1 f1 f1 00 f3 f3 f3 49 bc 00 00 00 00 00 fc ff df 4b 89 04 27 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 4c 8b 74 24 20 41 f7 c6 00 02 00 00 74 05 e8 0e ce 41 f6 bf 01 00 00 00 e8 34 RSP: 0018:ffffc90000a08aa0 EFLAGS: 00000a02 RAX: f3f3f300f1f1f1f1 RBX: ffff888028db3cb8 RCX: ffff88802edd9e40 RDX: 0000000000000100 RSI: 0000000000000004 RDI: ffff888028db3cb8 RBP: ffffc90000a08b20 R08: ffff888028db3c63 R09: 1ffff110051b678c R10: dffffc0000000000 R11: ffffed10051b678d R12: dffffc0000000000 R13: ffff888028db3c10 R14: 0000000000000a02 R15: 1ffff92000141154 FS: 00007faf05c09c80(0000) GS:ffff888125ae8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc97a26d68 CR3: 0000000061550000 CR4: 00000000003526f0 Call Trace: skb_dequeue+0x2e/0x150 net/core/skbuff.c:3897 garp_queue_xmit net/802/garp.c:272 [inline] garp_join_timer+0x8e/0x120 net/802/garp.c:424 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 0b 23 26 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90004be7358 EFLAGS: 00000206 RAX: 373d0bd57626a300 RBX: 0000000000000000 RCX: 373d0bd57626a300 RDX: 0000000000000001 RSI: ffffffff8ddae1af RDI: ffffffff8c036f00 RBP: ffffffff8173bd25 R08: 0000000000000000 R09: ffffffff8173bd25 R10: ffffc90004be7578 R11: fffff5200097ceb1 R12: 0000000000000002 R13: ffffffff8e33c820 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1169 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 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:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4770 [inline] slab_alloc_node mm/slub.c:5068 [inline] kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5075 alloc_empty_file+0x55/0x1d0 fs/file_table.c:237 path_openat+0x107/0x3830 fs/namei.c:4040 do_filp_open+0x1fa/0x410 fs/namei.c:4081 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: 0033:0x7faf05dc7c3a Code: 41 89 f2 48 89 54 24 e0 41 83 e2 40 75 2a 89 f0 f7 d0 a9 00 00 41 00 74 1f 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 77 2e c3 0f 1f 44 00 00 48 8d 44 24 08 c7 44 24 RSP: 002b:00007ffc97a28438 EFLAGS: 00000206 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007faf05dc7c3a RDX: 0000000000090800 RSI: 000055acf4db7150 RDI: 00000000ffffff9c RBP: 000055acf4dacdef R08: 00007faf05ea3ac0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffc97a28598 R13: 000055acf4dacde8 R14: 0000000000000001 R15: 000055acf4db7177 vkms_vblank_simulate: vblank timer overrun