INFO: task udevd:5767 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:23048 pid:5767 ppid:5137 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
io_schedule+0x80/0xd0 kernel/sched/core.c:9023
folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
folio_put_wait_locked mm/filemap.c:1493 [inline]
do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3786
read_mapping_folio include/linux/pagemap.h:898 [inline]
read_part_sector+0xd2/0x340 block/partitions/core.c:718
adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
check_partition block/partitions/core.c:138 [inline]
blk_add_partitions block/partitions/core.c:600 [inline]
bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
blkdev_get_whole+0x30d/0x390 block/bdev.c:672
blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
blkdev_open+0x152/0x360 block/fops.c:589
do_dentry_open+0x8c6/0x1500 fs/open.c:929
do_open fs/namei.c:3640 [inline]
path_openat+0x27f1/0x3230 fs/namei.c:3797
do_filp_open+0x1f5/0x430 fs/namei.c:3824
do_sys_openat2+0x134/0x1d0 fs/open.c:1421
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+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7feb2b8a7407
RSP: 002b:00007ffcbc411bd0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007feb2bf80880 RCX: 00007feb2b8a7407
RDX: 00000000000a0800 RSI: 0000562184158a90 RDI: ffffffffffffff9c
RBP: 000056218414e910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000562184166e00
R13: 0000562184166410 R14: 0000000000000000 R15: 0000562184166e00
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
7 locks held by kworker/1:1H/55:
2 locks held by getty/5526:
#0: ffff88802d4140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
1 lock held by udevd/5767:
#0: ffff88807dac54c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
5 locks held by kworker/u4:9/14670:
#0: ffff888017c73938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017c73938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#1: ffffc900038afd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900038afd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#2: ffffffff8e3b31d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x14c/0xbb0 net/core/net_namespace.c:606
#3: ffff88805fa6d3e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x116/0x310 drivers/net/wireguard/device.c:250
#4: ffffffff8d137840 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
1 lock held by dhcpcd-run-hook/12437:
#0: ffff88804ca03068 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline]
#0: ffff88804ca03068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_read+0xd6c/0x1310 fs/pipe.c:382
1 lock held by dhcpcd-run-hook/12441:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf3d/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 55 Comm: kworker/1:1H Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:50 [inline]
RIP: 0010:arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:24
Code: 90 08 00 49 89 c4 31 ff 48 89 c6 e8 26 74 54 00 4d 85 e4 74 2c 48 89 df 4c 89 e6 41 ff d6 84 c0 74 26 4c 89 ff e8 4c 92 08 00 <83> bd 78 ff ff ff 00 74 1c e8 be 6f 54 00 eb c1 e8 b7 6f 54 00 eb
RSP: 0000:ffffc900001efe88 EFLAGS: 00000296
RAX: ffffffff813b5301 RBX: ffffc900001eff40 RCX: ffff88801ca91e00
RDX: 0000000000000100 RSI: 0000000000000101 RDI: 0000000000000000
RBP: ffffc900001eff10 R08: ffff88801ca91e00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff816b70ed
R13: ffffc900001f02a0 R14: ffffffff8175b740 R15: ffffc900001efe88
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc3cfdc0a8 CR3: 000000000cf32000 CR4: 00000000003506e0
Call Trace:
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x270 mm/slub.c:3852
nft_synproxy_eval_v4+0x353/0x4e0 net/netfilter/nft_synproxy.c:60
nft_synproxy_do_eval+0x306/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
nft_do_chain+0x44e/0x1600 net/netfilter/nf_tables_core.c:288
nft_do_chain_inet+0x29b/0x380 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626
nf_hook include/linux/netfilter.h:259 [inline]
NF_HOOK+0x21d/0x3b0 include/linux/netfilter.h:302
NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304
__netif_receive_skb_one_core net/core/dev.c:5621 [inline]
__netif_receive_skb+0xcc/0x290 net/core/dev.c:5735
process_backlog+0x391/0x6f0 net/core/dev.c:6063
__napi_poll+0xc0/0x460 net/core/dev.c:6625
napi_poll net/core/dev.c:6692 [inline]
net_rx_action+0x616/0xc40 net/core/dev.c:6828
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:console_flush_all+0x8b1/0xd20 arch/x86/include/asm/irqflags.h:-1
Code: ed 01 00 00 e8 e0 82 1b 00 4d 85 ff 48 8b 5c 24 38 75 07 e8 d1 82 1b 00 eb 06 e8 ca 82 1b 00 fb 49 bf 00 00 00 00 00 fc ff df <48> 8b 44 24 58 42 0f b6 04 38 84 c0 0f 85 2f 02 00 00 80 3b 01 0f
RSP: 0000:ffffc90001396fe0 EFLAGS: 00000293
RAX: ffffffff816b90d6 RBX: ffffc9000139717f RCX: ffff88801ca91e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90001397150 R08: ffffffff911bf507 R09: 1ffffffff2237ea0
R10: dffffc0000000000 R11: fffffbfff2237ea1 R12: ffffffff8d8b7c60
R13: 1ffffffff19f96f8 R14: ffffffff8d8b7cb8 R15: dffffc0000000000
console_unlock+0xad/0x350 kernel/printk/printk.c:3069
vprintk_emit+0x497/0x610 kernel/printk/printk.c:2341
dev_vprintk_emit+0x356/0x410 drivers/base/core.c:4953
dev_printk_emit+0xef/0x140 drivers/base/core.c:4964
_dev_info+0x11f/0x170 drivers/base/core.c:5022
nbd_xmit_timeout+0x796/0xa90 drivers/block/nbd.c:489
blk_mq_rq_timed_out block/blk-mq.c:1565 [inline]
blk_mq_handle_expired+0x170/0x2c0 block/blk-mq.c:1633
bt_iter+0x2ed/0x3b0 block/blk-mq-tag.c:293
__sbitmap_for_each_set include/linux/sbitmap.h:286 [inline]
sbitmap_for_each_set+0x308/0x5e0 include/linux/sbitmap.h:307
bt_for_each block/blk-mq-tag.c:325 [inline]
blk_mq_queue_tag_busy_iter+0x47b/0x7f0 block/blk-mq-tag.c:534
blk_mq_timeout_work+0x1df/0x3e0 block/blk-mq.c:1675
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293