bisecting fixing commit since 1752938529c614a8ed4432ecce6ebc95d3b87207 building syzkaller on 0fa352f2d664766b3115daecc56ab8608986864b testing commit 1752938529c614a8ed4432ecce6ebc95d3b87207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 4178ee1022137e7348ffaeefdec9ed60f12cbd7d13ea2eb66a89867d78f3492b all runs: crashed: WARNING in tty_set_termios testing current HEAD ed99bf0e81b558df39f7db2fa96d0228be4198c6 testing commit ed99bf0e81b558df39f7db2fa96d0228be4198c6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 127b5fe26969e7555b64f6753fdc25f9ae59f58e05f0e283e0ac9cdca96e059c all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m49.331556954s (build: 19m50.512597782s, test: 6m26.704456022s) the crash still happens on HEAD commit msg: Linux 4.14.250 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1