bisecting fixing commit since 756db2ba8bde4ead58ceb54e9cbc71f526f9a98f building syzkaller on efe0f24dd913d90b2c6a2dbe7b8dac779c266144 testing commit 756db2ba8bde4ead58ceb54e9cbc71f526f9a98f compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 220a6c901c40c4ad610922fe56c992a3203127e793ed48d7d6039d280c6fc522 all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD 0447aa205abe1c0c016b4f7fa9d7c08d920b5c8e testing commit 0447aa205abe1c0c016b4f7fa9d7c08d920b5c8e compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 9b725db8b03b3dfb89ab62247ec7f99bbbfd8aaca0464946e66b4250f616e835 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 24m44.876198013s (build: 17m50.069933708s, test: 6m29.013876066s) the crash still happens on HEAD commit msg: Linux 4.14.254 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout