INFO: task udevd:6039 blocked in I/O wait 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:20552 pid:6039 tgid:6039 ppid:4995 task_flags:0x400140 flags:0x00080802
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
io_schedule+0x7f/0xd0 kernel/sched/core.c:8110
folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1324
folio_put_wait_locked mm/filemap.c:1493 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4089
read_mapping_folio include/linux/pagemap.h:1017 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:450
check_partition block/partitions/core.c:143 [inline]
blk_add_partitions block/partitions/core.c:591 [inline]
bdev_disk_changed+0x817/0x1770 block/partitions/core.c:695
blkdev_get_whole+0x380/0x510 block/bdev.c:756
bdev_open+0x31e/0xd30 block/bdev.c:965
blkdev_open+0x470/0x610 block/fops.c:697
do_dentry_open+0x785/0x14e0 fs/open.c:947
vfs_open+0x3b/0x340 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4858
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79814a7407
RSP: 002b:00007ffdaf90f760 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f7981c3a880 RCX: 00007f79814a7407
RDX: 00000000000a0800 RSI: 00005578344088c0 RDI: ffffffffffffff9c
RBP: 00005578343f7910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005578344505e0
R13: 0000557834405190 R14: 0000000000000000 R15: 00005578344505e0
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/47:
#0: ffff88801be8e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff88801be8e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc90000b77c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc90000b77c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffffffff8fdc1628 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
#3: ffffffff8fdd0300 (rtnl_mutex){+.+.}-{4:4}, at: wg_destruct+0x25/0x310 drivers/net/wireguard/device.c:246
4 locks held by kworker/u8:9/1173:
#0: ffff88801ae84140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff88801ae84140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc9000598fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc9000598fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffffffff8fdd0300 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
#3: ffffffff8e963068 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#3: ffffffff8e963068 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
2 locks held by getty/5383:
#0: ffff888036bee0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by udevd/6039:
#0: ffff88802750e350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
2 locks held by syz-executor/32261:
#0: ffffffff90311d10 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff90311d10 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff90311d10 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8fdd0300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8fdd0300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8fdd0300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4109
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5290 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:validate_chain kernel/locking/lockdep.c:3875 [inline]
RIP: 0010:__lock_acquire+0xaac/0x2cf0 kernel/locking/lockdep.c:5237
Code: 48 8d 3d 27 7d 92 0e 48 c7 c6 c2 92 0c 8e 67 48 0f b9 3a 90 31 c0 48 83 78 40 00 0f 84 5a 1b 00 00 48 09 dd 41 8b 45 20 89 c1 <81> e1 00 80 04 00 81 f9 00 00 04 00 0f 85 50 02 00 00 25 ff 1f 00
RSP: 0018:ffffc90002df76a8 EFLAGS: 00000002
RAX: 000000000004802c RBX: 00000000713fd876 RCX: 000000000004802c
RDX: 00000000c8988767 RSI: 00000000467974aa RDI: ffff88802954bd80
RBP: 25ee2b6d713fd876 R08: ffffffff8225909b R09: ffff8880b863f4a8
R10: dffffc0000000000 R11: fffffbfff2061b7f R12: ffff88802954c938
R13: ffff88802954c938 R14: ffff88802954bd80 R15: 0000000000000001
FS: 00007fbca1875780(0000) GS:ffff888125287000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fe2a97b008 CR3: 0000000033e8c000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
local_trylock_acquire include/linux/local_lock_internal.h:53 [inline]
alloc_from_pcs mm/slub.c:4743 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__kmalloc_cache_noprof+0x177/0x660 mm/slub.c:5414
kmalloc_noprof include/linux/slab.h:950 [inline]
slab_free_hook mm/slub.c:2641 [inline]
slab_free mm/slub.c:6250 [inline]
kmem_cache_free+0x156/0x650 mm/slub.c:6377
remove_vma mm/vma.c:473 [inline]
vms_complete_munmap_vmas+0x929/0xc60 mm/vma.c:1361
do_vmi_align_munmap+0x3b7/0x4b0 mm/vma.c:1604
do_vmi_munmap+0x252/0x2d0 mm/vma.c:1652
__vm_munmap+0x22c/0x3d0 mm/vma.c:3285
__do_sys_munmap mm/mmap.c:1079 [inline]
__se_sys_munmap mm/mmap.c:1076 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1076
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbca1976097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd7c84eec8 EFLAGS: 00000202 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000000009000 RCX: 00007fbca1976097
RDX: 00007fbca1963dd0 RSI: 0000000000009000 RDI: 00007fbca17ab000
RBP: 00007fbca17ab000 R08: 0000000000007e33 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd7c84ef00 R14: 0000000000000001 R15: 00007fbca1963dd0
----------------
Code disassembly (best guess):
0: 48 8d 3d 27 7d 92 0e lea 0xe927d27(%rip),%rdi # 0xe927d2e
7: 48 c7 c6 c2 92 0c 8e mov $0xffffffff8e0c92c2,%rsi
e: 67 48 0f b9 3a ud1 (%edx),%rdi
13: 90 nop
14: 31 c0 xor %eax,%eax
16: 48 83 78 40 00 cmpq $0x0,0x40(%rax)
1b: 0f 84 5a 1b 00 00 je 0x1b7b
21: 48 09 dd or %rbx,%rbp
24: 41 8b 45 20 mov 0x20(%r13),%eax
28: 89 c1 mov %eax,%ecx
* 2a: 81 e1 00 80 04 00 and $0x48000,%ecx <-- trapping instruction
30: 81 f9 00 00 04 00 cmp $0x40000,%ecx
36: 0f 85 50 02 00 00 jne 0x28c
3c: 25 .byte 0x25
3d: ff 1f lcall *(%rdi)