syzbot

snd_usb_toneport 5-1:0.0: Line 6 POD Studio UX2 found
snd_usb_toneport 5-1:0.0: set_interface failed
snd_usb_toneport 5-1:0.0: Line 6 POD Studio UX2 now disconnected
------------[ cut here ]------------
list_del corruption. prev->next should be ffff8881cf716d68, but was ffff8881ce1b6c28
WARNING: CPU: 0 PID: 5731 at lib/list_debug.c:51 __list_del_entry_valid+0x101/0x170 lib/list_debug.c:51
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 5731 Comm: kworker/0:5 Not tainted 5.1.0-rc3+ #8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xca/0x13e lib/dump_stack.c:113
 panic+0x292/0x5e1 kernel/panic.c:214
 __warn.cold+0x20/0x53 kernel/panic.c:571
 report_bug+0x262/0x2a0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:__list_del_entry_valid+0x101/0x170 lib/list_debug.c:51
Code: c4 08 31 c0 41 5c 41 5d c3 4c 89 e2 48 c7 c7 20 f7 d8 85 e8 1c 2a 35 ff 0f 0b 31 c0 eb c6 48 c7 c7 80 f7 d8 85 e8 0a 2a 35 ff <0f> 0b 31 c0 eb b4 48 c7 c7 e0 f7 d8 85 e8 f8 29 35 ff 0f 0b 31 c0
RSP: 0018:ffff8881cddc7078 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8881cf716c70 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8127bbcd RDI: ffffed1039bb8e01
RBP: ffff8881cf716c80 R08: ffff8881cd3ae000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881d17974a8
R13: ffff8881d7f9cd58 R14: ffff8881cf716c70 R15: ffff8881cf716d58
 __list_del_entry include/linux/list.h:117 [inline]
 list_del include/linux/list.h:125 [inline]
 snd_info_free_entry+0x132/0x340 sound/core/info.c:795
 snd_info_card_free+0x3e/0x80 sound/core/info.c:606
 snd_card_do_free sound/core/init.c:469 [inline]
 release_card_device+0x63/0xd0 sound/core/init.c:156
 device_release+0x78/0x210 drivers/base/core.c:1064
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:67 [inline]
 kobject_put+0x17d/0x270 lib/kobject.c:708
 put_device+0x1c/0x30 drivers/base/core.c:2205
 snd_card_free_when_closed+0x35/0x50 sound/core/init.c:493
 line6_disconnect.cold+0xa3/0xbc sound/usb/line6/driver.c:833
 line6_probe+0xb1e/0x1140 sound/usb/line6/driver.c:799
 usb_probe_interface+0x30d/0x7b0 drivers/usb/core/driver.c:361
 really_probe+0x296/0x680 drivers/base/dd.c:509
 driver_probe_device+0xf9/0x200 drivers/base/dd.c:671
 __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:778
 bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454
 __device_attach+0x21e/0x360 drivers/base/dd.c:844
 bus_probe_device+0x1ec/0x2a0 drivers/base/bus.c:514
 device_add+0xaf4/0x1700 drivers/base/core.c:2106
 usb_set_configuration+0xdf2/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0xa8/0x110 drivers/usb/core/driver.c:266
 really_probe+0x296/0x680 drivers/base/dd.c:509
 driver_probe_device+0xf9/0x200 drivers/base/dd.c:671
 __device_attach_driver+0x1c4/0x230 drivers/base/dd.c:778
 bus_for_each_drv+0x15e/0x1e0 drivers/base/bus.c:454
 __device_attach+0x21e/0x360 drivers/base/dd.c:844
 bus_probe_device+0x1ec/0x2a0 drivers/base/bus.c:514
 device_add+0xaf4/0x1700 drivers/base/core.c:2106
 usb_new_device.cold+0x8b8/0x1030 drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x1ac9/0x35a0 drivers/usb/core/hub.c:5432
 process_one_work+0x90a/0x1580 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x30e/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..