INFO: task udevd:8064 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23120 pid: 8064 ppid:  3562 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356
 wait_on_page_bit mm/filemap.c:1417 [inline]
 wait_on_page_locked include/linux/pagemap.h:688 [inline]
 wait_on_page_read mm/filemap.c:3437 [inline]
 do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480
 read_mapping_page include/linux/pagemap.h:515 [inline]
 read_part_sector+0xd4/0x4f0 block/partitions/core.c:726
 adfspart_check_ICS+0xc3/0xe40 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:148 [inline]
 blk_add_partitions block/partitions/core.c:611 [inline]
 bdev_disk_changed+0x933/0x16c0 block/partitions/core.c:697
 blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
 blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
 blkdev_open+0x12d/0x2c0 block/fops.c:466
 do_dentry_open+0x7ff/0xf80 fs/open.c:826
 do_open fs/namei.c:3616 [inline]
 path_openat+0x26f5/0x2fa0 fs/namei.c:3750
 do_filp_open+0x1e2/0x410 fs/namei.c:3777
 do_sys_openat2+0x150/0x4b0 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1715490407
RSP: 002b:00007ffcc9cc6620 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f17153a2880 RCX: 00007f1715490407
RDX: 00000000000a0800 RSI: 000055c222731430 RDI: ffffffffffffff9c
RBP: 000055c222730910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055c222757b60
R13: 000055c222748410 R14: 0000000000000000 R15: 000055c222757b60
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/154:
1 lock held by udevd/3562:
 #0: ffff8880209e6518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
1 lock held by dhcpcd/3855:
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x258/0x1a70 net/ipv4/devinet.c:1076
2 locks held by getty/3947:
 #0: ffff88802ca95098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by syz-executor/4185:
 #0: ffff8880209f0118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
 #1: ffff8881470fa468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071
3 locks held by kworker/0:5/4231:
 #0: ffff88802bcad138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000321fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
4 locks held by kworker/0:6/4234:
 #0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:483
 #1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
 #2: ffff8880b9027eb8 (krc.lock){..-.}-{2:2}, at: kfree_rcu_monitor+0x29/0x730 kernel/rcu/tree.c:3382
 #3: ffff8880b90280d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946
1 lock held by udevd/5078:
 #0: ffff8880209e6518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
3 locks held by kworker/0:14/5406:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9001d417d00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #2: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by kworker/0:21/5413:
 #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9001d507d00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
1 lock held by udevd/8064:
 #0: ffff888020bbbd18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
3 locks held by kworker/1:12/9730:
 #0: ffff88802bcad138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000e407d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
1 lock held by syz-executor/10629:
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5684
2 locks held by syz.0.1425/10760:
 #0: ffff8880209e6518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
 #1: ffff888020b37468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071
1 lock held by syz.5.1432/10775:
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: do_ipv6_setsockopt net/ipv6/ipv6_sockglue.c:417 [inline]
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: ipv6_setsockopt+0x4a1/0x3cc0 net/ipv6/ipv6_sockglue.c:1009
1 lock held by syz.5.1432/10776:
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: do_ipv6_setsockopt net/ipv6/ipv6_sockglue.c:417 [inline]
 #0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: ipv6_setsockopt+0x4a1/0x3cc0 net/ipv6/ipv6_sockglue.c:1009

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4185 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__lock_acquire+0xff9/0x7d10 kernel/locking/lockdep.c:-1
Code: 8b 7c 24 40 e8 88 2d 61 00 eb bb 44 89 e0 25 ff 1f 00 00 41 c1 ec 03 41 81 e4 00 60 00 00 41 09 c4 4c 89 fe 48 c1 ee 20 89 f0 <c1> c0 04 41 29 f4 44 31 e0 44 01 fe 41 29 c7 89 c1 c1 c1 06 44 31
RSP: 0018:ffffc90002f6eaa0 EFLAGS: 00000803
RAX: 00000000d1ee2549 RBX: 0000000000000091 RCX: ffff88807b314670
RDX: 0000000000000000 RSI: 00000000d1ee2549 RDI: ffffffff901d50d0
RBP: ffffc90002f6ecf0 R08: dffffc0000000000 R09: 1ffffffff203aa1a
R10: dffffc0000000000 R11: fffffbfff203aa1b R12: 00000000000000a0
R13: ffff88807b313b80 R14: 1ffff1100f6628cc R15: d1ee2549d20e726d
FS:  00005555759e9500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555575a0ca68 CR3: 0000000063e80000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 do_write_seqcount_begin_nested include/linux/seqlock.h:519 [inline]
 do_write_seqcount_begin include/linux/seqlock.h:545 [inline]
 psi_group_change+0x113/0x1150 kernel/sched/psi.c:710
 psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
 psi_sched_switch kernel/sched/stats.h:148 [inline]
 __schedule+0x1d02/0x43c0 kernel/sched/core.c:6390
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 blk_mq_freeze_queue_wait+0x107/0x190 block/blk-mq.c:152
 __loop_clr_fd+0x204/0xb90 drivers/block/loop.c:1382
 loop_clr_fd drivers/block/loop.c:1510 [inline]
 lo_ioctl+0x14c4/0x20f0 drivers/block/loop.c:1866
 blkdev_ioctl+0x33b/0x700 block/ioctl.c:604
 block_ioctl+0xac/0xf0 block/fops.c:496
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbd18deea6b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffdab81b8e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fbd18deea6b
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003
RBP: 00007ffdab81b97c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000117
R13: 00005555759fc9f0 R14: 00000000000a46d1 R15: 00007ffdab81b9d0
 </TASK>