INFO: task udevd:6724 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:22016 pid:6724 tgid:6724 ppid:4999 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 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+0x822/0x13a0 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+0x174/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb4c16a7407
RSP: 002b:00007ffcd3683cf0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c1dff880 RCX: 00007fb4c16a7407
RDX: 00000000000a0800 RSI: 0000556f13f297c0 RDI: ffffffffffffff9c
RBP: 0000556f13ef6910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000556f13f00840
R13: 0000556f13f04190 R14: 0000000000000000 R15: 0000556f13f00840
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:5/141:
#0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc90002f3fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc90002f3fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8fdc5180 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
2 locks held by getty/5391:
#0: ffff8880372350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5738:
#0: ffff888027749350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
1 lock held by udevd/6724:
#0: ffff888027641350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
1 lock held by syz.1.4076/21463:
#0: ffffffff8e962e78 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by syz.4.4079/21476:
#0: ffffffff8fdc5180 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fdc5180 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3441
#1: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
=============================================
NMI backtrace for cpu 0
CPU: 0 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+0x389/0x470 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20090 Comm: kworker/u8:22 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: bond4 bond_alb_monitor
RIP: 0010:__kasan_check_write+0xf/0x20 mm/kasan/shadow.c:37
Code: 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 ba 01 00 00 00 5c e5 ff ff 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc90000a08cc8 EFLAGS: 00000046
RAX: 1ffff110053de441 RBX: ffff888029ef2000 RCX: ffffffff8979380f
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888029ef2198
RBP: 0000000000000001 R08: ffffffff89b507ab R09: ffffffff8e95cca0
R10: dffffc0000000000 R11: ffffed10053de456 R12: ffff88806b4d1c00
R13: dffffc0000000000 R14: ffff888029ef2208 R15: 18b3575c07e477f2
FS: 0000000000000000(0000) GS:ffff8881253ab000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7a3e7ea2f8 CR3: 00000000758e2000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline]
__netif_schedule+0x5f/0x200 net/core/dev.c:3403
advance_sched+0xa3d/0xc20 net/sched/sch_taprio.c:993
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478
Code: 0f 84 44 ff ff ff e8 62 2a 21 00 fb eb 44 e8 5a 2a 21 00 e8 25 c9 00 0a 4d 85 f6 74 94 e8 4b 2a 21 00 fb 48 c7 c7 c0 f0 94 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 18
RSP: 0018:ffffc9000448e900 EFLAGS: 00000293
RAX: ffffffff81a49c55 RBX: ffffffff81a49acf RCX: ffff888060a60000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e94f0c0
RBP: ffffc9000448e9b0 R08: ffffffff902ff2f7 R09: 1ffffffff205fe5e
R10: dffffc0000000000 R11: fffffbfff205fe5f R12: 0000000000000000
R13: 0000000000000042 R14: 0000000000000200 R15: 1ffff92000891d24
_printk+0xdd/0x130 kernel/printk/printk.c:2504
gred_dequeue+0x4e6/0x6f0 net/sched/sch_gred.c:273
dequeue_skb net/sched/sch_generic.c:322 [inline]
qdisc_restart net/sched/sch_generic.c:427 [inline]
__qdisc_run+0x23f/0x1560 net/sched/sch_generic.c:445
qdisc_run include/net/pkt_sched.h:120 [inline]
__dev_xmit_skb net/core/dev.c:4292 [inline]
__dev_queue_xmit+0x1d26/0x3950 net/core/dev.c:4831
dev_queue_xmit include/linux/netdevice.h:3418 [inline]
neigh_hh_output include/net/neighbour.h:544 [inline]
neigh_output include/net/neighbour.h:558 [inline]
ip_finish_output2+0xc68/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
iptunnel_xmit+0x621/0xd10 net/ipv4/ip_tunnel_core.c:97
ip_tunnel_xmit+0x193a/0x1f20 net/ipv4/ip_tunnel.c:845
__gre_xmit net/ipv4/ip_gre.c:491 [inline]
gre_tap_xmit+0x5a7/0x7a0 net/ipv4/ip_gre.c:779
__netdev_start_xmit include/linux/netdevice.h:5368 [inline]
netdev_start_xmit include/linux/netdevice.h:5377 [inline]
xmit_one net/core/dev.c:3888 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3904
sch_direct_xmit+0x251/0x4c0 net/sched/sch_generic.c:372
__dev_xmit_skb net/core/dev.c:4209 [inline]
__dev_queue_xmit+0x180f/0x3950 net/core/dev.c:4831
dev_queue_xmit include/linux/netdevice.h:3418 [inline]
alb_send_lp_vid+0x348/0x550 drivers/net/bonding/bond_alb.c:949
alb_send_learning_packets+0x12c/0x300 drivers/net/bonding/bond_alb.c:1012
bond_alb_monitor+0x3d5/0x17e0 drivers/net/bonding/bond_alb.c:1563
process_one_work kernel/workqueue.c:3314 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
kthread+0x389/0x470 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
----------------
Code disassembly (best guess):
0: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1)
7: 00 00 00 00
b: 90 nop
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: 90 nop
12: 90 nop
13: 90 nop
14: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 90 nop
19: 90 nop
1a: 90 nop
1b: f3 0f 1e fa endbr64
1f: 89 f6 mov %esi,%esi
21: 48 8b 0c 24 mov (%rsp),%rcx
25: ba 01 00 00 00 mov $0x1,%edx
* 2a: e9 5c e5 ff ff jmp 0xffffe58b <-- trapping instruction
2f: 66 66 66 2e 0f 1f 84 data16 data16 cs nopw 0x0(%rax,%rax,1)
36: 00 00 00 00 00
3b: 90 nop
3c: 90 nop
3d: 90 nop
3e: 90 nop
3f: 90 nop