INFO: task kworker/0:2:13739 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:23576 pid:13739 tgid:13739 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 usb_kill_urb drivers/usb/core/urb.c:713 [inline] usb_kill_urb+0x253/0x320 drivers/usb/core/urb.c:699 usb_start_wait_urb+0x250/0x4b0 drivers/usb/core/message.c:65 usb_internal_control_msg drivers/usb/core/message.c:103 [inline] usb_control_msg+0x326/0x4a0 drivers/usb/core/message.c:154 get_bMaxPacketSize0.constprop.0+0xd0/0x1f0 drivers/usb/core/hub.c:4815 hub_port_init+0x690/0x3a70 drivers/usb/core/hub.c:5011 hub_port_connect drivers/usb/core/hub.c:5460 [inline] hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] port_event drivers/usb/core/hub.c:5831 [inline] hub_event+0x2c67/0x4fa0 drivers/usb/core/hub.c:5913 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 2 locks held by getty/5581: #0: ffff8880325e40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 5 locks held by kworker/0:2/13739: #0: ffff888020afe548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000be4fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88814638d198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #2: ffff88814638d198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5859 #3: ffff8881463a0510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] #3: ffff8881463a0510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline] #3: ffff8881463a0510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] #3: ffff8881463a0510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline] #3: ffff8881463a0510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2906/0x4fa0 drivers/usb/core/hub.c:5913 #4: ffff888145b10368 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline] #4: ffff888145b10368 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] #4: ffff888145b10368 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline] #4: ffff888145b10368 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x292b/0x4fa0 drivers/usb/core/hub.c:5913 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 20392 Comm: kworker/u8:11 Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_mcast_mla_update RIP: 0010:batadv_mcast_mla_forw_flags_get net/batman-adv/multicast.c:252 [inline] RIP: 0010:batadv_mcast_mla_flags_get net/batman-adv/multicast.c:289 [inline] RIP: 0010:__batadv_mcast_mla_update net/batman-adv/multicast.c:909 [inline] RIP: 0010:batadv_mcast_mla_update+0x505/0x31c0 net/batman-adv/multicast.c:948 Code: 85 0b 29 00 00 4d 8b 6d 00 49 81 fd a0 03 02 9b 0f 84 06 01 00 00 e8 5a 5d 7c f6 49 8d 7d 10 48 89 f8 48 c1 e8 03 0f b6 04 18 <84> c0 74 06 0f 8e 02 29 00 00 45 0f b6 75 10 bf 03 00 00 00 44 89 RSP: 0018:ffffc90010147ac8 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff8b3ef261 RDX: ffff888028158000 RSI: ffffffff8b3ef236 RDI: ffff8880769f0810 RBP: ffffed10024b69b1 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000000 R11: ffffffff8b3ef18a R12: 0000000000000000 R13: ffff8880769f0800 R14: 0000000000000000 R15: ffff8880125b5730 FS: 0000000000000000(0000) GS:ffff888124ab2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056011858c600 CR3: 000000000e180000 CR4: 00000000003526f0 DR0: 0000000000000007 DR1: 000000000000000b DR2: 0000000000000002 DR3: 7fffffffffffffff DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245