bisecting fixing commit since bd634aa6416382439890b78f7be0023020a86207 building syzkaller on 6a81331a1d4c744da9204d02ec88d558f7eea9c9 testing commit bd634aa6416382439890b78f7be0023020a86207 with gcc (GCC) 8.4.1 20210217 kernel signature: 73335d922ffebf8c497a583c22b4ac8363cded98c8ea4cc39fa9d217a01147c6 all runs: crashed: WARNING in hsr_addr_subst_dest testing current HEAD cfb41ef9deb1e6572ac218ddfcec9567e5d1c101 testing commit cfb41ef9deb1e6572ac218ddfcec9567e5d1c101 with gcc (GCC) 8.4.1 20210217 kernel signature: 4db0ef35a160a2c892bc942594932080b2d90191341b1f4fe1cbf412a02ff54b all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m56.925087321s (build: 14m16.433150174s, test: 12m17.986636104s) 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: hci0 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout