bisecting fixing commit since c9fcc1545c3bb19f4e04b1c82bf5c2856fef39bd building syzkaller on 9e8eaa75a18a5cf8102e862be692c0781759e51b testing commit c9fcc1545c3bb19f4e04b1c82bf5c2856fef39bd compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b8d896598b8f0bbfe40b82c3694fb9fb83cca3bbc5cb6a094e3d5e6ce0af964e all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD dffb5c6ff09c51ed585e3e7665143df103867fc8 testing commit dffb5c6ff09c51ed585e3e7665143df103867fc8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ea6b507f7e3ab407b112892f8ff613952d8016311f300c34b21a3daaf262d4cb all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 24m59.101931075s (build: 18m11.09973416s, test: 6m20.564252596s) the crash still happens on HEAD commit msg: Linux 4.14.280 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout