INFO: task udevd:28721 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23520 pid:28721 tgid:28721 ppid:5190   task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
 __schedule_loop kernel/sched/core.c:6990 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7005
 io_schedule+0x7f/0xd0 kernel/sched/core.c:7832
 folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323
 __folio_lock mm/filemap.c:1699 [inline]
 folio_lock include/linux/pagemap.h:1170 [inline]
 __filemap_get_folio_mpol+0x13e/0xb00 mm/filemap.c:1954
 __filemap_get_folio include/linux/pagemap.h:774 [inline]
 truncate_inode_pages_range+0x48b/0xe30 mm/truncate.c:413
 kill_bdev block/bdev.c:91 [inline]
 blkdev_flush_mapping+0x109/0x2f0 block/bdev.c:728
 blkdev_put_whole block/bdev.c:735 [inline]
 bdev_release+0x417/0x650 block/bdev.c:1160
 blkdev_release+0x15/0x20 block/fops.c:705
 __fput+0x44f/0xa70 fs/file_table.c:469
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x70f/0x23c0 kernel/exit.c:976
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
 get_signal+0x1284/0x1330 kernel/signal.c:3034
 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9fbb2a7407
RSP: 002b:00007ffd4c185470 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: fffffffffffffffc RBX: 00007f9fbba57880 RCX: 00007f9fbb2a7407
RDX: 0000000000000200 RSI: 00007f9fbba56000 RDI: 0000000000000009
RBP: 00005650877ec050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 00005650877e5a48 R15: 00007f9fbbb7e39c
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #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
1 lock held by dhcpcd/5485:
 #0: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x23d/0x370 net/ipv6/addrconf.c:4803
2 locks held by getty/5579:
 #0: ffff8880330250a0 (&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
3 locks held by kworker/u8:26/9361:
 #0: ffff8880323b0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
 #0: ffff8880323b0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
 #1: ffffc9000492fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #1: ffffc9000492fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
 #2: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198
2 locks held by kworker/1:13/23843:
 #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
1 lock held by udevd/28721:
 #0: ffff888026c7e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144
2 locks held by syz.0.8057/11365:
 #0: ffffffff8fbb8d70 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
 #1: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: cfg802154_pernet_exit+0x19/0xe0 net/ieee802154/core.c:351
5 locks held by syz.1.8066/11411:
 #0: ffffffff8fbb8d70 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
 #1: ffffffff8f91f930 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x200/0x2f0 drivers/infiniband/core/device.c:1187
 #2: ffffffff8f91faf0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x238/0x2f0 drivers/infiniband/core/device.c:1192
 #3: ffff88802b00cfb0 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xf0/0x650 drivers/infiniband/core/device.c:951
 #4: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x173/0x7f0 drivers/infiniband/core/verbs.c:2053
1 lock held by syz.2.8070/11426:
 #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
3 locks held by syz.2.8070/11438:
 #0: ffffffff901363e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff901363e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff901363e8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
 #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.2.8070/11439:
 #0: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8fbc7508 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120
2 locks held by syz.3.8071/11428:
 #0: ffff88803c7a07c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
 #0: ffff88803c7a07c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
 #0: ffff88803c7a07c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1454
 #1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961

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

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 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:436
 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: 5807 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
RIP: 0010:lock_is_held_type+0xdf/0x150 kernel/locking/lockdep.c:5941
Code: eb 1c 83 fd ff 74 12 31 c0 f6 43 22 03 0f 95 c0 31 db 39 c5 0f 94 c3 eb 05 bb 01 00 00 00 48 c7 c7 19 9e 16 8e e8 21 18 00 00 <b8> ff ff ff ff 65 0f c1 05 04 40 6d 07 83 f8 01 75 25 9c 58 a9 00
RSP: 0018:ffffc900039b7710 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8e169e19 RDI: ffffffff8c27b200
RBP: 00000000ffffffff R08: ffffffff901141b7 R09: 1ffffffff2022836
R10: dffffc0000000000 R11: fffffbfff2022837 R12: 0000000000000046
R13: ffff888055023d00 R14: ffff8880b873ade0 R15: 0000000000000000
FS:  000055558137b540(0000) GS:ffff888125565000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc864de6158 CR3: 0000000035894000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lock_is_held include/linux/lockdep.h:249 [inline]
 lockdep_assert_rq_held kernel/sched/sched.h:1600 [inline]
 cpuacct_charge+0xe0/0x320 kernel/sched/cpuacct.c:341
 cgroup_account_cputime include/linux/cgroup.h:742 [inline]
 update_se+0x2b5/0x620 kernel/sched/fair.c:1255
 update_curr+0x77/0x4f0 kernel/sched/fair.c:1301
 dequeue_entity kernel/sched/fair.c:5414 [inline]
 dequeue_entities+0x1a7/0x3710 kernel/sched/fair.c:7094
 dequeue_task_fair+0x1fd/0x7b0 kernel/sched/fair.c:7193
 block_task kernel/sched/core.c:2170 [inline]
 try_to_block_task kernel/sched/core.c:6530 [inline]
 __schedule+0x666/0x52d0 kernel/sched/core.c:6843
 __schedule_loop kernel/sched/core.c:6990 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7005
 do_nanosleep+0x1c2/0x620 kernel/time/hrtimer.c:2124
 hrtimer_nanosleep+0x188/0x390 kernel/time/hrtimer.c:2171
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
 __se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368
 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: 0033:0x7f1ffcb57917
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd54891810 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055558137b540 RCX: 00007f1ffcb57917
RDX: 00007ffd54891850 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd54891d30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007ffd5489188c R14: 00007ffd54891920 R15: 0000000000000000
 </TASK>