INFO: task udevd:4310 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:24768 pid: 4310 ppid:  3563 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0x815/0xe00 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:731
 adfspart_check_ICS+0xbf/0xe00 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:148 [inline]
 blk_add_partitions block/partitions/core.c:616 [inline]
 bdev_disk_changed+0x917/0x16b0 block/partitions/core.c:702
 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:3608 [inline]
 path_openat+0x2682/0x2f30 fs/namei.c:3742
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
 do_sys_openat2+0x142/0x4a0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1280
 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: 0033:0x7f121cf6c407
RSP: 002b:00007fff5aecd9f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f121ce7e880 RCX: 00007f121cf6c407
RDX: 00000000000a0800 RSI: 0000563fe50f5a90 RDI: ffffffffffffff9c
RBP: 0000563fe50e5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000563fe5107040
R13: 0000563fe50fd410 R14: 0000000000000000 R15: 0000563fe5107040
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c460 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by dhcpcd/3855:
 #0: ffffffff8d220288 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x273/0x6e0 net/socket.c:1219
 #1: ffffffff8d237b88 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xd2/0x610 net/8021q/vlan.c:579
2 locks held by getty/3951:
 #0: ffff88802bbb3098 (&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+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:4/4248:
 #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc900031bfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
1 lock held by udevd/4310:
 #0: ffff8880205f4518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
3 locks held by kworker/0:9/4312:
4 locks held by kworker/u4:10/4332:
 #0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc9000450fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d22bf10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
 #3: ffffffff8d237b88 (rtnl_mutex){+.+.}-{3:3}, at: wiphy_unregister+0x234/0xa40 net/wireless/core.c:1019
5 locks held by kworker/0:19/5804:
 #0: ffff888017df7138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc9000448fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff888023c24220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff888023c24220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x5560 drivers/usb/core/hub.c:5827
 #3: ffff888023c275c0 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3168 [inline]
 #3: ffff888023c275c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5393 [inline]
 #3: ffff888023c275c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
 #3: ffff888023c275c0 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5799 [inline]
 #3: ffff888023c275c0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2234/0x5560 drivers/usb/core/hub.c:5881
 #4: ffff88801f61f768 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5394 [inline]
 #4: ffff88801f61f768 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
 #4: ffff88801f61f768 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5799 [inline]
 #4: ffff88801f61f768 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x226d/0x5560 drivers/usb/core/hub.c:5881
2 locks held by syz-executor/6816:
 #0: ffffffff8d237b88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d237b88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
 #1: ffffffff8c120ee8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c120ee8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
1 lock held by syz.2.649/6869:

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

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 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 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: 6869 Comm: syz.2.649 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x7b/0x290 mm/kasan/generic.c:189
Code: 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 <0f> 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee e9 1c 01 00 00 44 89 cb
RSP: 0018:ffffc900045cf6a0 EFLAGS: 00000046
RAX: ffffc900045cf701 RBX: ffffffffffffffff RCX: ffffffff819c4c62
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900045cf760
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520008b9eed
R10: fffff520008b9eee R11: 1ffff920008b9eec R12: ffffea00015ea180
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000001
FS:  00007f015c8d76c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f015c4b6000 CR3: 00000000298ff000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 page_cache_delete mm/filemap.c:127 [inline]
 __delete_from_page_cache+0x112/0x6b0 mm/filemap.c:232
 delete_from_page_cache+0x121/0x190 mm/filemap.c:266
 truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
 shmem_undo_range+0x4dc/0x1880 mm/shmem.c:960
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x20d/0xa00 mm/shmem.c:1145
 evict+0x485/0x870 fs/inode.c:647
 __dentry_kill+0x431/0x650 fs/dcache.c:586
 dentry_kill+0xb8/0x290 fs/dcache.c:-1
 dput+0xd8/0x1a0 fs/dcache.c:893
 __fput+0x5ee/0x930 fs/file_table.c:319
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f015e66e84a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007f015c8d6e00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00007f015e66e84a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000020429
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 00007f015c8d6ef0 R14: 00007f015c8d6eb0 R15: 00007f01544b7000
 </TASK>