bisecting fixing commit since 4e68c9b0763ff55eaa69d6e519f07515f1c9037b building syzkaller on f115ae985a399ddce060f448097b8068450a8f48 testing commit 4e68c9b0763ff55eaa69d6e519f07515f1c9037b compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 965ff7215e49aa5ac8a827bd64a24eb6670ab6938bde23c663cf80e265885624 all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD f11944f1aa1cda3fd8b4edc71e3cf9dceb40234f testing commit f11944f1aa1cda3fd8b4edc71e3cf9dceb40234f compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 0ed1be6a6bbda9b4ac5039aa9089c4c9f10573d9bd97adbbbfd0f81b63ed66dc all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 25m50.971008862s (build: 18m55.120156931s, test: 6m17.312499756s) the crash still happens on HEAD commit msg: Linux 4.14.248 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x040f 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: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout