INFO: task udevd:5961 blocked in I/O wait 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:22168 pid:5961 tgid:5961 ppid:5198 task_flags:0x400140 flags:0x00080802
Call Trace:
context_switch kernel/sched/core.c:5349 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7044 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7059
io_schedule+0x7f/0xd0 kernel/sched/core.c:7886
folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1492 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4083
read_mapping_folio include/linux/pagemap.h:1028 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:723
adfspart_check_POWERTEC+0x92/0xef0 block/partitions/acorn.c:454
check_partition block/partitions/core.c:142 [inline]
blk_add_partitions block/partitions/core.c:590 [inline]
bdev_disk_changed+0x7ba/0x1550 block/partitions/core.c:694
blkdev_get_whole+0x380/0x510 block/bdev.c:764
bdev_open+0x31e/0xd30 block/bdev.c:973
blkdev_open+0x470/0x610 block/fops.c:697
do_dentry_open+0x785/0x14e0 fs/open.c:949
vfs_open+0x3b/0x340 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4830
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa9996a7407
RSP: 002b:00007ffcd493b8b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa999de3880 RCX: 00007fa9996a7407
RDX: 00000000000a0800 RSI: 000055915ccfe340 RDI: ffffffffffffff9c
RBP: 000055915ccfd910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055915cd66510
R13: 000055915cd0b190 R14: 0000000000000000 R15: 000055915cd66510
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7606e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7606e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7606e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/35:
#0: ffff88801b09c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x849/0x1720 kernel/workqueue.c:3257
#1: ffffc90000ab7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x870/0x1720 kernel/workqueue.c:3258
#2: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
3 locks held by kworker/u8:3/37:
#0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880597b0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6443 [inline]
#2: ffff8880597b0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x4a0 net/wireless/core.c:425
3 locks held by kworker/u8:5/78:
#0: ffff888033130148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x849/0x1720 kernel/workqueue.c:3257
#1: ffffc900025cfc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x870/0x1720 kernel/workqueue.c:3258
#2: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198
2 locks held by getty/5582:
#0: ffff888033bec0a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5961:
#0: ffff8880277d9358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
2 locks held by syz.1.2027/12244:
#0: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8e766978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e766978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.2.2031/12263:
#0: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x722/0xbe0 net/core/rtnetlink.c:6964
2 locks held by syz.2.2031/12269:
#0: ffffffff901230f8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff901230f8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff901230f8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
1 lock held by syz.0.2026/12272:
#0: ffffffff8fbd1f08 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bc/0x1e30 drivers/net/tun.c:3078
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0x1002/0x1060 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 3496 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:758 [inline]
RIP: 0010:batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
RIP: 0010:batadv_iv_ogm_schedule+0x731/0xf50 net/batman-adv/bat_iv_ogm.c:873
Code: 15 38 28 f6 48 c7 c7 e0 06 76 8e 48 8b b4 24 98 00 00 00 e8 81 1e 28 f6 e8 cc cd 31 f6 48 8b 84 24 90 00 00 00 42 0f b6 04 30 <84> c0 75 16 48 ff c3 41 8b 45 00 48 39 c3 73 21 e8 0a e5 4b f6 e9
RSP: 0018:ffffc9000e14f940 EFLAGS: 00000287
RAX: 0000000000000000 RBX: 0000000000000286 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8e17d3f6 RDI: ffff888034389e80
RBP: ffffc9000e14fa90 R08: ffffffff8b7a898a R09: ffffffff8e7606e0
R10: dffffc0000000000 R11: fffffbfff2023dff R12: ffff88805be6e880
R13: ffff88805be6e890 R14: dffffc0000000000 R15: ffff88805be95430
FS: 0000000000000000(0000) GS:ffff888125441000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000003a3030 CR3: 0000000076492000 CR4: 00000000003526f0
Call Trace:
batadv_iv_send_outstanding_bat_ogm_packet+0x6c8/0x7e0 net/batman-adv/bat_iv_ogm.c:1709
process_one_work+0x963/0x1720 kernel/workqueue.c:3285
process_scheduled_works kernel/workqueue.c:3376 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3457
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
----------------
Code disassembly (best guess):
0: 15 38 28 f6 48 adc $0x48f62838,%eax
5: c7 c7 e0 06 76 8e mov $0x8e7606e0,%edi
b: 48 8b b4 24 98 00 00 mov 0x98(%rsp),%rsi
12: 00
13: e8 81 1e 28 f6 call 0xf6281e99
18: e8 cc cd 31 f6 call 0xf631cde9
1d: 48 8b 84 24 90 00 00 mov 0x90(%rsp),%rax
24: 00
25: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax
* 2a: 84 c0 test %al,%al <-- trapping instruction
2c: 75 16 jne 0x44
2e: 48 ff c3 inc %rbx
31: 41 8b 45 00 mov 0x0(%r13),%eax
35: 48 39 c3 cmp %rax,%rbx
38: 73 21 jae 0x5b
3a: e8 0a e5 4b f6 call 0xf64be549
3f: e9 .byte 0xe9