INFO: task syz.0.3140:19521 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3140      state:D stack:28160 pid:19521 tgid:19519 ppid:18432  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 bdev_open+0xe0/0xd30 block/bdev.c:961
 blkdev_open+0x470/0x610 block/fops.c:698
 do_dentry_open+0x785/0x14e0 fs/open.c:949
 vfs_open+0x3b/0x340 fs/open.c:1081
 do_open fs/namei.c:4671 [inline]
 path_openat+0x2e08/0x3860 fs/namei.c:4830
 do_file_open+0x23e/0x4a0 fs/namei.c:4859
 do_sys_openat2+0x113/0x200 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fafd7b5cece
RSP: 002b:00007fafd8a23b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fafd8a246c0 RCX: 00007fafd7b5cece
RDX: 0000000000040400 RSI: 00007fafd8a23c00 RDI: ffffffffffffff9c
RBP: 00007fafd8a23c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fafd7e16128 R14: 00007fafd7e16090 R15: 00007ffde97de228
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5594:
 #0: ffff888037e990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/8534:
 #0: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #0: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by kworker/u8:27/10305:
 #0: ffff888032b01148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
 #1: ffffc90003cb7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
 #2: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4199
1 lock held by udevd/16608:
 #0: ffff888026fa0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
3 locks held by kworker/1:1/16865:
 #0: ffff88801b06b548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
 #1: ffffc90004407c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
 #2: ffff88807ed6a240
 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0 drivers/net/netdevsim/fib.c:1490
1 lock held by syz.0.3140/19521:
 #0: ffff888026fa0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
3 locks held by syz-executor/21394:
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
 #1: ffff88808dd7d528 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50
 #2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.8.3473/21693:
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8fbd0488 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xfd9/0x1030 kernel/hung_task.c:515
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 5e 6b 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 7d 19 00 fb f4 <e9> 7c ea 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000242
RAX: 0000000002a59eb5 RBX: ffffffff819aa27d RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8defab6a RDI: ffffffff8c27f980
RBP: ffffc90000197f10 R08: ffff8880b873395b R09: 1ffff110170e672b
R10: dffffc0000000000 R11: ffffed10170e672c R12: ffffffff9011c4b0
R13: 1ffff11003c57000 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125555000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f00c039ae9c CR3: 000000006dfee000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000e08e000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1bd/0x500 kernel/sched/idle.c:332
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>