bisecting fixing commit since 4e68c9b0763ff55eaa69d6e519f07515f1c9037b building syzkaller on f115ae985a399ddce060f448097b8068450a8f48 testing commit 4e68c9b0763ff55eaa69d6e519f07515f1c9037b compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 57ea4eebce9130641b47a2dd6a30ce5fdc7132163f7ee52e438b47ef37258328 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: 4130977c76bc2b4d874bc275417f7b41d660bd139be135d73a88d20495d73c45 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 29m27.987126815s (build: 18m10.079964436s, test: 10m33.478094849s) 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: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b 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: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout