INFO: task kworker/1:4:4256 blocked for more than 145 seconds.
Not tainted 6.1.138-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4 state:D stack:24672 pid:4256 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
usb_kill_urb+0x1c2/0x2f0 drivers/usb/core/urb.c:728
usb_start_wait_urb+0x189/0x4b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x22f/0x3e0 drivers/usb/core/message.c:153
get_bMaxPacketSize0 drivers/usb/core/hub.c:4770 [inline]
hub_port_init+0xcd3/0x2ac0 drivers/usb/core/hub.c:4967
hub_port_connect drivers/usb/core/hub.c:5418 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
port_event drivers/usb/core/hub.c:5785 [inline]
hub_event+0x2724/0x5210 drivers/usb/core/hub.c:5867
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8c92b2f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8c92bb10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
#0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4016:
#0: ffff8880305fe098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4252:
#0: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#0: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
5 locks held by kworker/1:4/4256:
#0: ffff88801aee2138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90003d67d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffff88814672a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline]
#2: ffff88814672a190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x5210 drivers/usb/core/hub.c:5813
#3: ffff88814672d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3172 [inline]
#3: ffff88814672d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5385 [inline]
#3: ffff88814672d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#3: ffff88814672d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#3: ffff88814672d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2079/0x5210 drivers/usb/core/hub.c:5867
#4: ffff8881467b6468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5386 [inline]
#4: ffff8881467b6468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#4: ffff8881467b6468 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#4: ffff8881467b6468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x20a9/0x5210 drivers/usb/core/hub.c:5867
1 lock held by syz-executor/4262:
#0: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#0: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
2 locks held by kworker/0:11/5330:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004687d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
1 lock held by udevd/6070:
#0: ffff88801796b4c0 (mapping.invalidate_lock#2){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:813 [inline]
#0: ffff88801796b4c0 (mapping.invalidate_lock#2){.+.+}-{3:3}, at: page_cache_ra_unbounded+0xd8/0x770 mm/readahead.c:226
4 locks held by kworker/u4:19/6753:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004047d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8db27350 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594
#3: ffffffff8c930500 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4019
1 lock held by dhcpcd/10298:
#0: ffff8880756ce130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1756 [inline]
#0: ffff8880756ce130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/10299:
#0: ffff888065472130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1756 [inline]
#0: ffff888065472130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/10300:
#0: ffff888026f42130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1756 [inline]
#0: ffff888026f42130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/10301:
#0: ffff888024e98130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1756 [inline]
#0: ffff888024e98130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/10302:
#0: ffff888047c42130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1756 [inline]
#0: ffff888047c42130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 6.1.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:unwind_next_frame+0x190c/0x20b0 arch/x86/kernel/unwind_orc.c:639
Code: 00 00 00 00 fc ff df 48 8b 4c 24 18 0f b6 04 01 84 c0 0f 85 40 01 00 00 c7 03 00 00 00 00 31 c0 48 81 c4 a0 00 00 00 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 49 89 d6 49 89 d4 4c 89 e8 4c 29 e0 48 89
RSP: 0018:ffffc900001b68e0 EFLAGS: 00000282
RAX: 0000000000000101 RBX: ffffc900001b69c0 RCX: 0000000000000100
RDX: ffffc900001b6901 RSI: dffffc0000000000 RDI: 00000000ffffffff
RBP: ffffffff8ef5b16a R08: ffffc900001b7930 R09: ffffc900001b6958
R10: fffff52000036d2d R11: 1ffff92000036d2b R12: ffff888017741dc0
R13: dffffc0000000000 R14: ffffc900001b6918 R15: ffffc900001b7940
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558e98e608 CR3: 0000000078395000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
__kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3422
skb_ext_maybe_cow net/core/skbuff.c:6493 [inline]
skb_ext_add+0x1c1/0x910 net/core/skbuff.c:6567
nf_bridge_unshare net/bridge/br_netfilter_hooks.c:165 [inline]
br_nf_forward_ip+0xc9/0x1140 net/bridge/br_netfilter_hooks.c:712
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:614
nf_hook include/linux/netfilter.h:257 [inline]
NF_HOOK+0x20f/0x3d0 include/linux/netfilter.h:300
__br_forward+0x41f/0x600 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver+0xb5/0x150 net/bridge/br_forward.c:189
br_flood+0x2fc/0x450 net/bridge/br_forward.c:231
br_handle_frame_finish+0x12bf/0x1710 net/bridge/br_input.c:198
br_nf_hook_thresh+0x3b2/0x480 net/bridge/br_netfilter_hooks.c:1187
br_nf_pre_routing_finish_ipv6+0x9e1/0xda0 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:302 [inline]
br_nf_pre_routing_ipv6+0x349/0x670 net/bridge/br_netfilter_ipv6.c:243
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:260 [inline]
br_handle_frame+0x919/0x12f0 net/bridge/br_input.c:406
__netif_receive_skb_core+0xfc5/0x3840 net/core/dev.c:5463
__netif_receive_skb_one_core net/core/dev.c:5567 [inline]
__netif_receive_skb+0x74/0x290 net/core/dev.c:5683
process_backlog+0x37c/0x6e0 net/core/dev.c:6011
__napi_poll+0xc0/0x460 net/core/dev.c:6578
napi_poll net/core/dev.c:6645 [inline]
net_rx_action+0x5b1/0xad0 net/core/dev.c:6759
handle_softirqs+0x2a1/0x920 kernel/softirq.c:578
run_ksoftirqd+0x98/0xf0 kernel/softirq.c:945
smpboot_thread_fn+0x64a/0xa40 kernel/smpboot.c:164
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295