INFO: task udevd:4180 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23088 pid: 4180 ppid:  3561 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: 0033:0x7f52f32a3407
RSP: 002b:00007fffd55ca390 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f52f31b5880 RCX: 00007f52f32a3407
RDX: 00000000000a0800 RSI: 00005556d9e6a980 RDI: ffffffffffffff9c
RBP: 00005556d9e59910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005556d9e6dba0
R13: 00005556d9e71410 R14: 0000000000000000 R15: 00005556d9e6dba0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31f360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:3/1182:
5 locks held by kworker/1:2/1754:
 #0: ffff888142396538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90004e57d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff8880241b0220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
 #2: ffff8880241b0220 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x55e0 drivers/usb/core/hub.c:5827
 #3: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:483
 #4: ffff8880b9127888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
2 locks held by getty/3951:
 #0: ffff88814ccec098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
1 lock held by udevd/4180:
 #0: ffff888020a0c518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
1 lock held by udevd/4182:
 #0: ffff888020a14518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
2 locks held by udevd/4438:
 #0: ffff88802063f918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
 #1: ffff88802077c468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
3 locks held by kworker/0:15/5479:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000334fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8c323cf0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
2 locks held by udevd/11198:
 #0: ffff88802063a518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
 #1: ffff88802069b468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
2 locks held by kworker/0:20/11218:
 #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc900039efd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by syz.9.1420/11432:
 #0: ffff88802881e0e0 (&type->s_umount_key#25/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229
 #1: ffffc900036210f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 #1: ffffc900036210f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline]
 #1: ffffc900036210f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_end+0x304/0x42d0 fs/reiserfs/journal.c:4025
 #2: ffffc90003621180 (&journal->j_flush_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 #2: ffffc90003621180 (&journal->j_flush_mutex){+.+.}-{3:3}, at: flush_journal_list+0x180/0x1ba0 fs/reiserfs/journal.c:1366
2 locks held by syz.2.1575/12371:
 #0: ffff888075913810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #0: ffff888075913810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline]
 #0: ffff888075913810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1345
 #1: ffffffff8c323de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c323de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/0:21/12383:
 #0: ffff888142396538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90002fffd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff8880241b0220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
 #2: ffff8880241b0220 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x55e0 drivers/usb/core/hub.c:5827

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12406 Comm: dhcpcd-run-hook Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:task_css include/linux/cgroup.h:496 [inline]
RIP: 0010:blk_cgroup_congested include/linux/blk-cgroup.h:283 [inline]
RIP: 0010:__cgroup_throttle_swaprate+0x1b8/0x530 mm/swapfile.c:3809
Code: ff eb 77 48 c7 c7 b8 4c 34 8c be ff ff ff ff e8 ce 94 05 08 89 c5 31 ff 89 c6 e8 83 64 c1 ff 85 ed 74 07 e8 1a 61 c1 ff eb 50 <49> 83 c7 2c 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 1d 03
RSP: 0000:ffffc90002e0fb08 EFLAGS: 00000246
RAX: ffffffff81b7e7cd RBX: 00fff00000000000 RCX: ffff88807b245940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff203b018
R10: dffffc0000000000 R11: fffffbfff203b019 R12: dffffc0000000000
R13: ffffc90002e0fd80 R14: ffffffff8c347400 R15: ffff88807b245940
FS:  00007fb4cc3e1c80(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563311a2c4dc CR3: 0000000079070000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 cgroup_throttle_swaprate include/linux/swap.h:728 [inline]
 wp_page_copy+0x5e2/0x2050 mm/memory.c:3080
 handle_pte_fault mm/memory.c:4668 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1f06/0x4410 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1355
 handle_page_fault arch/x86/mm/fault.c:1443 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7fb4cc6d1878
Code: fc ff 41 ff ce 49 8b 45 00 75 11 89 a8 08 03 00 00 48 89 df 6a 01 5e e8 92 b0 ff ff 8b 43 1c 8d 50 01 48 c1 e0 04 48 03 43 10 <89> 53 1c 48 93 49 8b 45 00 83 4b 04 ff 48 83 c0 48 80 3d 7f a0 07
RSP: 002b:00007ffd5cb9ffd0 EFLAGS: 00010206
RAX: 0000563311a2c4c0 RBX: 0000563311a2c4c0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000003081 R08: 00007fb4cc67cb60 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000563311a28b40
R13: 00007fb4cc74b460 R14: 00000000ffffffff R15: 0000000000000000
 </TASK>