bisecting fixing commit since 964f3712e6a7447d9d3203f2be3f6c50e78ea179 building syzkaller on fd5118098a3df4301eba91aeca37119ccb209403 testing commit 964f3712e6a7447d9d3203f2be3f6c50e78ea179 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: cfd1b7b298353ad4031012af4fe0311cf743227f27819f94d4521474350bcd07 all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD cd529693461026636f76d0395a42cb2439bbd368 testing commit cd529693461026636f76d0395a42cb2439bbd368 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 61848c983aab183ca03e5c99073189ac03100131e94693d74936c60871ae4733 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 24m2.569905315s (build: 17m17.848081813s, test: 6m18.508790835s) the crash still happens on HEAD commit msg: Linux 4.14.253 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: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout