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URB 00000000d868e7c8 submitted while active
WARNING: CPU: 0 PID: 6209 at drivers/usb/core/urb.c:363 usb_submit_urb+0x11cf/0x14e0 drivers/usb/core/urb.c:363
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 6209 Comm: kworker/0:2 Not tainted 4.20.0-rc6-next-20181210+ #164
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_power_efficient hub_init_func2
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
kobject: 'loop5' (000000002482138a): kobject_uevent_env
 panic+0x2ad/0x632 kernel/panic.c:214
kobject: 'loop5' (000000002482138a): fill_kobj_path: path = '/devices/virtual/block/loop5'
 __warn.cold.8+0x20/0x4f kernel/panic.c:571
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:usb_submit_urb+0x11cf/0x14e0 drivers/usb/core/urb.c:363
Code: ee e8 e5 29 6c fc 45 84 ed 0f 85 e2 f6 ff ff e8 07 29 6c fc 48 89 de 48 c7 c7 20 64 b4 88 c6 05 b3 ef 1f 05 01 e8 d1 47 35 fc <0f> 0b e9 c0 f6 ff ff c7 45 a0 01 00 00 00 e9 65 f7 ff ff 41 bc ed
RSP: 0018:ffff8881d49ff4e8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8881c78a8800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff816621c5 RDI: 0000000000000005
RBP: ffff8881d49ff558 R08: ffff8881d2adc140 R09: ffffed103b585020
R10: ffffed103b585020 R11: ffff8881dac28107 R12: 00000000fffffff0
R13: 0000000000000000 R14: ffff8881cd236940 R15: 0000000000000009
 hub_activate+0xd5f/0x19f0 drivers/usb/core/hub.c:1225
 hub_init_func2+0x1e/0x30 drivers/usb/core/hub.c:1250
 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153
 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..