WARNING in usb_submit_urb

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: fa5941f4 Linux 4.14.114
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14416ecca00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d7780000df8e070e
dashboard link: https://syzkaller.appspot.com/bug?extid=1d7638ae7f056c7f8583
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1d7638...@syzkaller.appspotmail.com

URB ffff8880a1068d00 submitted while active
------------[ cut here ]------------
WARNING: CPU: 1 PID: 7176 at drivers/usb/core/urb.c:363
usb_submit_urb.cold+0x1b/0x2c drivers/usb/core/urb.c:363
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 7176 Comm: kworker/1:4 Not tainted 4.14.114 #4
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:17 [inline]
dump_stack+0x138/0x19c lib/dump_stack.c:53
panic+0x1f2/0x438 kernel/panic.c:182
__warn.cold+0x2f/0x34 kernel/panic.c:546
report_bug+0x216/0x254 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:944
RIP: 0010:usb_submit_urb.cold+0x1b/0x2c drivers/usb/core/urb.c:363
RSP: 0018:ffff888063b1fbb0 EFLAGS: 00010286
RAX: 000000000000002b RBX: ffff88808115b680 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888063b0c8d0 RDI: ffffed100c763f6c
RBP: ffff888063b1fc10 R08: 000000000000002b R09: ffff888063b0c8c8
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a1068d00
R13: ffff88808115b690 R14: ffff88808115b820 R15: 0000000000000009
hub_activate+0x972/0x14e0 drivers/usb/core/hub.c:1223
hub_init_func2+0x1e/0x30 drivers/usb/core/hub.c:1248
process_one_work+0x868/0x1610 kernel/workqueue.c:2114
worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
kthread+0x31c/0x430 kernel/kthread.c:232
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Kernel Offset: disabled
Rebooting in 86400 seconds..


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.