INFO: task udevd:7851 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:23848 pid:7851 tgid:7851 ppid:5202 task_flags:0x400140 flags:0x00080000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5263 [inline]
__schedule+0x1836/0x4ed0 kernel/sched/core.c:6871
__schedule_loop kernel/sched/core.c:6953 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6968
io_schedule+0x80/0xd0 kernel/sched/core.c:7800
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit_lock+0xec/0x4f0 kernel/sched/wait_bit.c:93
out_of_line_wait_on_bit_lock+0x123/0x170 kernel/sched/wait_bit.c:120
wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline]
__lock_buffer fs/buffer.c:71 [inline]
lock_buffer include/linux/buffer_head.h:432 [inline]
block_read_full_folio+0x38f/0x830 fs/buffer.c:2439
filemap_read_folio+0x117/0x380 mm/filemap.c:2496
filemap_update_page mm/filemap.c:2583 [inline]
filemap_get_pages+0x1692/0x1df0 mm/filemap.c:2713
filemap_read+0x3f6/0x11a0 mm/filemap.c:2800
blkdev_read_iter+0x30a/0x440 block/fops.c:861
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x55a/0xa30 fs/read_write.c:572
ksys_read+0x145/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe374ca7407
RSP: 002b:00007ffdb760a210 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fe37535b880 RCX: 00007fe374ca7407
RDX: 0000000000000200 RSI: 00007fe375358000 RDI: 0000000000000009
RBP: 000055f80466e030 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000018
R13: 0000000000001000 R14: 000055f8046658f8 R15: 00007fe37542039c
</TASK>
INFO: task syz.9.1333:11420 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1333 state:D stack:24456 pid:11420 tgid:11419 ppid:6836 task_flags:0x400140 flags:0x00080002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5263 [inline]
__schedule+0x1836/0x4ed0 kernel/sched/core.c:6871
__schedule_loop kernel/sched/core.c:6953 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6968
io_schedule+0x80/0xd0 kernel/sched/core.c:7800
folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1159 [inline]
__find_get_block_slow fs/buffer.c:205 [inline]
find_get_block_common+0x2e9/0xfc0 fs/buffer.c:1408
bdev_getblk+0x53/0x6e0 include/linux/gfp.h:-1
__getblk include/linux/buffer_head.h:380 [inline]
sb_getblk include/linux/buffer_head.h:386 [inline]
__ext4_get_inode_loc+0x83a/0x1040 fs/ext4/inode.c:4866
ext4_get_inode_loc fs/ext4/inode.c:4969 [inline]
ext4_reserve_inode_write+0x18b/0x360 fs/ext4/inode.c:6305
__ext4_mark_inode_dirty+0x14b/0x700 fs/ext4/inode.c:6483
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6520
__mark_inode_dirty+0x390/0x13c0 fs/fs-writeback.c:2587
generic_update_time fs/inode.c:2161 [inline]
inode_update_time fs/inode.c:2174 [inline]
touch_atime+0x59b/0x6d0 fs/inode.c:2246
file_accessed include/linux/fs.h:2254 [inline]
iterate_dir+0x438/0x570 fs/readdir.c:111
__do_sys_getdents64 fs/readdir.c:410 [inline]
__se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdddc98f6c9
RSP: 002b:00007fdddd876038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fdddcbe5fa0 RCX: 00007fdddc98f6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007fdddca11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdddcbe6038 R14: 00007fdddcbe5fa0 R15: 00007ffe5378df28
</TASK>
Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/60:
2 locks held by getty/5589:
#0:
ffff88802fc2b0a0
(&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by udevd/7851:
#0: ffff88814957aa28 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff88814957aa28 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2f8/0x440 block/fops.c:860
#1: ffff88814957abc8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline]
#1: ffff88814957abc8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_update_page mm/filemap.c:2549 [inline]
#1: ffff88814957abc8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_get_pages+0x8d9/0x1df0 mm/filemap.c:2713
3 locks held by syz.9.1333/11420:
#0: ffff88807a9c62b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1255
#1: ffff88807e001720 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
#2: ffff888075d9c420 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2254 [inline]
#2: ffff888075d9c420 (sb_writers#4){.+.+}-{0:0}, at: iterate_dir+0x438/0x570 fs/readdir.c:111
3 locks held by kworker/u8:23/15968:
#0: ffff88814dc37148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236
#1: ffffc90004aafb80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237
#2: ffffffff8f2daa88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f2daa88 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
3 locks held by syz-executor/16034:
#0: ffffffff8ea6a6e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ea6a6e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8ea6a6e8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f2daa88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f2daa88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f2daa88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
#2: ffffffff8df431f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8df431f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
=============================================
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 10/25/2025
Call Trace:
<TASK>
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+0xfb5/0x1000 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
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1167 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
Code: 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 41 57 41 56 53 65 ff 05 50 99 ce 10 e8 0b a7 b3 09 <89> c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd d0
RSP: 0018:ffffc900040df398 EFLAGS: 00000282
RAX: 0000000000000000 RBX: ffffffff816ab664 RCX: 7006e52236164200
RDX: 0000000000000000 RSI: ffffffff8bbf8140 RDI: ffffffff8bbf8100
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81742ff5
R10: ffffc900040df538 R11: fffff5200081bea9 R12: 1ffff9200081be9d
R13: ffffc900040df520 R14: ffffc900040df4e8 R15: ffffffff81742ff5
FS: 0000000000000000(0000) GS:ffff888125ebc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb33a5b3ad8 CR3: 00000000755ce000 CR4: 00000000003526f0
Call Trace:
<TASK>
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd4/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
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
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6663 [inline]
kmem_cache_free+0x197/0x640 mm/slub.c:6774
skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1091
skb_release_all net/core/skbuff.c:1166 [inline]
__kfree_skb net/core/skbuff.c:1180 [inline]
sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1218
kfree_skb_reason include/linux/skbuff.h:1322 [inline]
kfree_skb include/linux/skbuff.h:1331 [inline]
ieee80211_iface_work+0xb30/0x12d0 net/mac80211/iface.c:1792
cfg80211_wiphy_work+0x2ab/0x470 net/wireless/core.c:438
process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
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
</TASK>