bisecting fixing commit since 3242aa3a635c0958671ee1e4b0958dcc7c4e5c79 building syzkaller on 4c37c133e4bf703d023995535f1e264d8658e08e testing commit 3242aa3a635c0958671ee1e4b0958dcc7c4e5c79 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: edf7dd1ac6491608bd41ffe05d4476d9357bad94d18f2816ed4b48178ad05c4c run #0: crashed: SYZFAIL: wrong response packet run #1: crashed: SYZFAIL: clone failed run #2: crashed: SYZFAIL: clone failed run #3: OK run #4: OK run #5: crashed: SYZFAIL: clone failed run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: crashed: SYZFAIL: clone failed run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing current HEAD cd529693461026636f76d0395a42cb2439bbd368 testing commit cd529693461026636f76d0395a42cb2439bbd368 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 74ba1a7dd7b4ff07d11f8da6fe4634424f55cb929e2e7d4913c00bf3df83d806 all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 32m50.382281098s (build: 19m47.878583883s, test: 12m36.514557969s) 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: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout