INFO: task udevd:4406 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:23792 pid: 4406 ppid: 3560 flags:0x00004002
Call Trace:
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: 0033:0x7f09a3f2e407
RSP: 002b:00007ffc8b02dc80 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f09a3e40880 RCX: 00007f09a3f2e407
RDX: 00000000000a0800 RSI: 000055795159a4c0 RDI: ffffffffffffff9c
RBP: 0000557951585910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000557951599ba0
R13: 000055795159d410 R14: 0000000000000000 R15: 0000557951599ba0
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by udevd/3560:
2 locks held by getty/3948:
#0: ffff88802c3a9098 (&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/4406:
#0: ffff888020592d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
3 locks held by kworker/1:17/5086:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc90002fcfd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by kworker/0:21/5863:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000337fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by syz.9.876/8419:
1 lock held by syz.9.902/8536:
1 lock held by syz.7.906/8538:
#0: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#0: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
2 locks held by dhcpcd-run-hook/8563:
=============================================
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 10/25/2025
Call Trace:
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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4690 Comm: kworker/u4:10 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x5a73/0x7d10 kernel/locking/lockdep.c:5039
Code: 00 00 eb 12 c7 44 24 68 00 00 00 00 49 b8 00 00 00 00 00 fc ff df 48 c7 84 24 20 01 00 00 0e 36 e0 45 48 8b 84 24 d0 00 00 00 <4a> c7 04 00 00 00 00 00 4a c7 44 00 08 00 00 00 00 4a c7 44 00 10
RSP: 0018:ffffc90005417820 EFLAGS: 00000093
RAX: 1ffff92000a82f28 RBX: ffff888020bfc668 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d10c0
RBP: ffffc90005417a70 R08: dffffc0000000000 R09: 1ffffffff203a218
R10: dffffc0000000000 R11: fffffbfff203a219 R12: 21e6a9aa9ddad20c
R13: ffff888020bfbb80 R14: ffff888020bfc660 R15: ffff888020bfc6e0
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ec40341d4 CR3: 000000007e2c3000 CR4: 00000000003506f0
Call Trace:
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
rcu_read_lock include/linux/rcupdate.h:740 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0xc9/0x5c0 net/batman-adv/network-coding.c:723
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287