INFO: task udevd:12133 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:21832 pid:12133 tgid:12133 ppid:5199 task_flags:0x400140 flags:0x00080802
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
io_schedule+0x80/0xd0 kernel/sched/core.c:7789
folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1487 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4078
read_mapping_folio include/linux/pagemap.h:1017 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:722
adfspart_check_POWERTEC+0x8c/0xf30 block/partitions/acorn.c:454
check_partition block/partitions/core.c:141 [inline]
blk_add_partitions block/partitions/core.c:589 [inline]
bdev_disk_changed+0x75f/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:765
bdev_open+0x31e/0xd30 block/bdev.c:974
blkdev_open+0x457/0x600 block/fops.c:698
do_dentry_open+0x7ce/0x1420 fs/open.c:962
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x340e/0x3dd0 fs/namei.c:4787
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc64d8a7407
RSP: 002b:00007ffd880fbee0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc64df9c880 RCX: 00007fc64d8a7407
RDX: 00000000000a0800 RSI: 000056068acd7460 RDI: ffffffffffffff9c
RBP: 000056068acb1910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000056068acc4e20
R13: 000056068acbf190 R14: 0000000000000000 R15: 000056068acc4e20
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5592:
#0: ffff888033b100a0 (&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+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by udevd/12133:
#0: ffff88802487a358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
3 locks held by syz.0.3295/19160:
=============================================
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 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19160 Comm: syz.0.3295 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__lock_acquire+0x347/0x2cf0 kernel/locking/lockdep.c:-1
Code: e2 01 c1 e2 12 44 09 ea c1 e3 14 09 d3 8b 14 24 c1 e2 13 41 c1 e4 15 41 09 d4 41 09 cc 41 09 dc 45 89 64 c7 20 41 89 7c c7 24 <4c> 89 7c 24 20 4d 8d 2c c7 41 81 e4 ff 1f 00 00 4c 0f a3 25 21 e7
RSP: 0018:ffffc90003dc6f10 EFLAGS: 00000002
RAX: 000000000000000a RBX: 0000000000020000 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffffffff81743f85 R09: ffffffff8df41a20
R10: ffffc90003dc7278 R11: fffff520007b8e51 R12: 0000000000020007
R13: 0000000000020000 R14: ffff88802d198000 R15: ffff88802d198b30
FS: 00007f3bb30b06c0(0000) GS:ffff888125f35000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3c4692 CR3: 0000000077e7a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_noprof+0x41d/0x800 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
new_dir fs/proc/proc_sysctl.c:966 [inline]
get_subdir fs/proc/proc_sysctl.c:1010 [inline]
sysctl_mkdir_p fs/proc/proc_sysctl.c:1320 [inline]
__register_sysctl_table+0xba1/0x1340 fs/proc/proc_sysctl.c:1395
neigh_sysctl_register+0x9a2/0xa80 net/core/neighbour.c:3886
devinet_sysctl_register+0xad/0x200 net/ipv4/devinet.c:2714
inetdev_init+0x2a4/0x4e0 net/ipv4/devinet.c:291
inetdev_event+0x2f1/0x15b0 net/ipv4/devinet.c:1590
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
call_netdevice_notifiers net/core/dev.c:2282 [inline]
register_netdevice+0x15bd/0x1a70 net/core/dev.c:11429
register_netdev+0x40/0x60 net/core/dev.c:11507
ip6_tnl_init_net+0x259/0x3b0 net/ipv6/ip6_tunnel.c:2307
ops_init+0x35c/0x5c0 net/core/net_namespace.c:137
setup_net+0x110/0x330 net/core/net_namespace.c:446
copy_net_ns+0x3e3/0x570 net/core/net_namespace.c:581
create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3bb218f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3bb30b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f3bb23e6090 RCX: 00007f3bb218f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007f3bb2213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3bb23e6128 R14: 00007f3bb23e6090 R15: 00007ffe0a091dd8