bisecting fixing commit since 1d177c0872ab99ac8d1fe09376a56c2911a837c0
building syzkaller on 26967e354e030f6a022b7a60a7c9899ec25923aa
testing commit 1d177c0872ab99ac8d1fe09376a56c2911a837c0 with gcc (GCC) 8.4.1 20210217
kernel signature: cc52889ab5dd4db2ea8a7a7e890881051fde405ad72248d6389d59cf73bd0955
all runs: crashed: WARNING in __btrfs_close_devices
testing current HEAD cfb41ef9deb1e6572ac218ddfcec9567e5d1c101
testing commit cfb41ef9deb1e6572ac218ddfcec9567e5d1c101 with gcc (GCC) 8.4.1 20210217
kernel signature: f1e9932e34789356ed7578917a6cc2eb94ca3f796265c4e5d6a3e45887bddff4
all runs: crashed: unregister_netdevice: waiting for DEV to become free
revisions tested: 2, total time: 21m47.236419817s (build: 14m48.882592212s, test: 6m32.538706796s)
the crash still happens on HEAD
commit msg: Linux 4.14.237
crash: unregister_netdevice: waiting for DEV to become free
unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1
Bluetooth: hci3 command 0x0409 tx timeout
Bluetooth: hci0 command 0x0409 tx timeout
Bluetooth: hci1 command 0x0409 tx timeout
Bluetooth: hci4 command 0x0409 tx timeout
Bluetooth: hci5 command 0x0409 tx timeout
Bluetooth: hci2 command 0x0409 tx timeout
Bluetooth: hci1 command 0x041b tx timeout
Bluetooth: hci0 command 0x041b tx timeout
Bluetooth: hci3 command 0x041b tx timeout
Bluetooth: hci2 command 0x041b tx timeout
Bluetooth: hci5 command 0x041b tx timeout
Bluetooth: hci4 command 0x041b tx timeout
Bluetooth: hci3 command 0x040f tx timeout
Bluetooth: hci0 command 0x040f tx timeout
Bluetooth: hci1 command 0x040f tx timeout
Bluetooth: hci4 command 0x040f tx timeout
Bluetooth: hci5 command 0x040f tx timeout
Bluetooth: hci2 command 0x040f tx timeout
Bluetooth: hci1 command 0x0419 tx timeout
Bluetooth: hci0 command 0x0419 tx timeout
Bluetooth: hci3 command 0x0419 tx timeout
Bluetooth: hci2 command 0x0419 tx timeout
Bluetooth: hci5 command 0x0419 tx timeout
Bluetooth: hci4 command 0x0419 tx timeout