bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207
building syzkaller on a343ba6b077a3efe7feb57783dcbb7496d2c3572
testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207
compiler: gcc version 8.4.1 20210217 (GCC)
kernel signature: ac886b24c3a48651fb4e104cf7b5534ea7932516a0b1445e2f4e4102b93a540f
all runs: crashed: INFO: task hung in grab_super
testing current HEAD 74766a973637a02c32c04c1c6496e114e4855239
testing commit 74766a973637a02c32c04c1c6496e114e4855239
compiler: gcc version 8.4.1 20210217 (GCC)
kernel signature: 7cf6424a5621e924a5757387a3646e2f7105476be2d9bb4d37b9a97624c6dc8c
all runs: crashed: unregister_netdevice: waiting for DEV to become free
revisions tested: 2, total time: 28m8.364075792s (build: 17m27.826562656s, test: 10m12.210129932s)
the crash still happens on HEAD
commit msg: Linux 4.14.275
crash: unregister_netdevice: waiting for DEV to become free
unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1
Bluetooth: hci1 command 0x0409 tx timeout
Bluetooth: hci3 command 0x0409 tx timeout
Bluetooth: hci5 command 0x0409 tx timeout
Bluetooth: hci2 command 0x0409 tx timeout
Bluetooth: hci4 command 0x0409 tx timeout
Bluetooth: hci0 command 0x0409 tx timeout
Bluetooth: hci1 command 0x041b tx timeout
Bluetooth: hci0 command 0x041b tx timeout
Bluetooth: hci4 command 0x041b tx timeout
Bluetooth: hci2 command 0x041b tx timeout
Bluetooth: hci5 command 0x041b tx timeout
Bluetooth: hci3 command 0x041b tx timeout
Bluetooth: hci3 command 0x040f tx timeout
Bluetooth: hci5 command 0x040f tx timeout
Bluetooth: hci2 command 0x040f tx timeout
Bluetooth: hci4 command 0x040f tx timeout
Bluetooth: hci0 command 0x040f tx timeout
Bluetooth: hci1 command 0x040f tx timeout
Bluetooth: hci1 command 0x0419 tx timeout
Bluetooth: hci0 command 0x0419 tx timeout
Bluetooth: hci4 command 0x0419 tx timeout
Bluetooth: hci2 command 0x0419 tx timeout
Bluetooth: hci5 command 0x0419 tx timeout
Bluetooth: hci3 command 0x0419 tx timeout