bisecting fixing commit since 9dfbac0e6b8600043de8dc85ed072f5f1342dc15 building syzkaller on 44068e196185e2f5a7c94629b6245cdde008b140 testing commit 9dfbac0e6b8600043de8dc85ed072f5f1342dc15 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: fda366845255c5286aede011e813e69c934d71d79c0dbf3bceec4185c1fe4a1d 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: 80dceebc9c96d2f65309e49850c0e56a196b853a709cf40ed324b42528993c85 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 29m11.19433243s (build: 22m11.778841738s, test: 6m21.482107082s) the crash still happens on HEAD commit msg: Linux 4.14.280 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout