bisecting fixing commit since 964f3712e6a7447d9d3203f2be3f6c50e78ea179 building syzkaller on 4d1b57d4d1aa7f8938163f8debd9293c062482b0 testing commit 964f3712e6a7447d9d3203f2be3f6c50e78ea179 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 0759cc3d4c9a7558ba3948638a11902f0fdfb04ad13e0fb829dd38bbb4d054ca all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD 162b95d01320370b80cb2d5724cea4ae538ac740 testing commit 162b95d01320370b80cb2d5724cea4ae538ac740 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 8a83ded94eea809b133ee0c12e44c5a1d3c1ef55c9ac9bfb09e1d9272fb04466 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 22m49.754888107s (build: 16m14.280908354s, test: 6m8.995329725s) the crash still happens on HEAD commit msg: Linux 4.14.244 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout