INFO: task udevd:4352 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:24448 pid: 4352 ppid: 3560 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356
wait_on_page_bit mm/filemap.c:1417 [inline]
wait_on_page_locked include/linux/pagemap.h:688 [inline]
wait_on_page_read mm/filemap.c:3437 [inline]
do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480
read_mapping_page include/linux/pagemap.h:515 [inline]
read_part_sector+0xd4/0x4f0 block/partitions/core.c:726
adfspart_check_ICS+0xbf/0xe00 block/partitions/acorn.c:360
check_partition block/partitions/core.c:148 [inline]
blk_add_partitions block/partitions/core.c:611 [inline]
bdev_disk_changed+0x917/0x16b0 block/partitions/core.c:697
blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3616 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3750
do_filp_open+0x1b3/0x3e0 fs/namei.c:3777
do_sys_openat2+0x142/0x4a0 fs/open.c:1255
do_sys_open fs/open.c:1271 [inline]
__do_sys_openat fs/open.c:1287 [inline]
__se_sys_openat fs/open.c:1282 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1282
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fea7f544407
RSP: 002b:00007ffe3fadd780 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fea7f456880 RCX: 00007fea7f544407
RDX: 00000000000a0800 RSI: 00005566b6fae900 RDI: ffffffffffffff9c
RBP: 00005566b6f9d910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005566b6fbe7d0
R13: 00005566b6fb5410 R14: 0000000000000000 R15: 00005566b6fbe7d0
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by udevd/3560:
#0: ffff888020256518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff888020305468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071
2 locks held by getty/3944:
#0: ffff88802c1dd098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4182:
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x86b/0xa40 net/core/dev.c:10696
2 locks held by kworker/1:4/4238:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000313fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
3 locks held by kworker/0:7/4249:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc900031efd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:6/4289:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc900032cfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
3 locks held by kworker/0:12/4340:
#0: ffff88802acd7538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003b9fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
1 lock held by udevd/4352:
#0: ffff888020705d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
2 locks held by kworker/1:12/4407:
#0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003f9fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
3 locks held by kworker/u4:8/4921:
#0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003ae7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
2 locks held by kworker/u4:11/5180:
#0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
1 lock held by syz.3.838/7859:
#0: ffff888020705d18 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1ab/0x320 block/bdev.c:1053
1 lock held by syz.3.838/7860:
#0: ffff888020705d18 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1ab/0x320 block/bdev.c:1053
4 locks held by kworker/u4:14/9644:
3 locks held by kworker/u4:15/9732:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003c47d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
1 lock held by syz-executor/10386:
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681
1 lock held by syz.7.1186/10460:
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x463/0xe50 net/core/dev_ioctl.c:521
6 locks held by syz.8.1178/10494:
#0: ffffffff96450eb8 (&rdma_nl_types[idx].sem){.+.+}-{3:3}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline]
#0: ffffffff96450eb8 (&rdma_nl_types[idx].sem){.+.+}-{3:3}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
#0: ffffffff96450eb8 (&rdma_nl_types[idx].sem){.+.+}-{3:3}, at: rdma_nl_rcv+0x2f9/0x970 drivers/infiniband/core/netlink.c:259
#1: ffffffff8d026db0 (link_ops_rwsem){++++}-{3:3}, at: nldev_newlink+0x332/0x4e0 drivers/infiniband/core/nldev.c:1701
#2: ffffffff8d019ed0 (devices_rwsem){++++}-{3:3}, at: enable_device_and_get+0xfb/0x3c0 drivers/infiniband/core/device.c:1330
#3: ffffffff8d01a090 (rdma_nets_rwsem){++++}-{3:3}, at: add_compat_devs drivers/infiniband/core/device.c:1033 [inline]
#3: ffffffff8d01a090 (rdma_nets_rwsem){++++}-{3:3}, at: enable_device_and_get+0x269/0x3c0 drivers/infiniband/core/device.c:1346
#4: ffff888044668fe8 (&device->compat_devs_mutex){+.+.}-{3:3}, at: add_one_compat_dev+0xee/0x5c0 drivers/infiniband/core/device.c:951
#5: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: ib_get_eth_speed+0x149/0x4b0 drivers/infiniband/core/verbs.c:1905
1 lock held by syz.8.1178/10495:
#0: ffff888020256518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
1 lock held by syz.9.1192/10516:
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3ab/0x1e70 drivers/net/tun.c:3052
1 lock held by syz.9.1192/10517:
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
#0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3440
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4289 Comm: kworker/1:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x60 kernel/kcov.c:206
Code: 48 8b 3d d0 6b f1 0b 48 89 de 5b e9 d7 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00
RSP: 0018:ffffc90000dcfd70 EFLAGS: 00000206
RAX: ffffffff889b59a5 RBX: 0000000000000001 RCX: ffff88802a119dc0
RDX: 0000000000000302 RSI: ffffffff8b0d3b00 RDI: ffffffff8a59e800
RBP: ffffc90000dcff80 R08: dffffc0000000000 R09: ffffc90000dcfed0
R10: fffff520001b9fde R11: 1ffff920001b9fda R12: 0000000000000001
R13: dffffc0000000000 R14: ffffffff8d6aeca0 R15: ffff88807ecea110
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ef1f0d138 CR3: 00000000224c8000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
local_bh_enable+0x5/0x20 include/linux/bottom_half.h:31
ip6t_do_table+0x12f9/0x14b0 net/ipv6/netfilter/ip6_tables.c:377
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584
nf_hook include/linux/netfilter.h:257 [inline]
NF_HOOK+0x4c9/0x610 include/linux/netfilter.h:300
br_nf_forward_ip+0xc5c/0x10a0 net/bridge/br_netfilter_hooks.c:732
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584
nf_hook include/linux/netfilter.h:257 [inline]
NF_HOOK+0x1eb/0x370 include/linux/netfilter.h:300
__br_forward+0x41f/0x600 net/bridge/br_forward.c:115
br_handle_frame_finish+0x1018/0x12c0 net/bridge/br_input.c:180
br_nf_hook_thresh+0x3b2/0x480 net/bridge/br_netfilter_hooks.c:1155
br_nf_pre_routing_finish_ipv6+0x903/0xc80 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:302 [inline]
br_nf_pre_routing_ipv6+0x359/0x650 net/bridge/br_netfilter_ipv6.c:237
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:242 [inline]
br_handle_frame+0x89b/0x1180 net/bridge/br_input.c:384
__netif_receive_skb_core+0xfb0/0x35d0 net/core/dev.c:5419
__netif_receive_skb_one_core net/core/dev.c:5523 [inline]
__netif_receive_skb+0x74/0x290 net/core/dev.c:5639
process_backlog+0x364/0x780 net/core/dev.c:6516
__napi_poll+0xc0/0x430 net/core/dev.c:7075
napi_poll net/core/dev.c:7142 [inline]
net_rx_action+0x4a8/0x9c0 net/core/dev.c:7232
handle_softirqs+0x328/0x820 kernel/softirq.c:576
do_softirq+0x13b/0x200 kernel/softirq.c:477
__local_bh_enable_ip+0x174/0x1b0 kernel/softirq.c:401
spin_unlock_bh include/linux/spinlock.h:409 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:736 [inline]
nsim_dev_trap_report_work+0x7c3/0xb40 drivers/net/netdevsim/dev.c:762
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287