bisecting fixing commit since 397a88b2cc869c823bf40bc403d36a62afec1edd building syzkaller on f89ed068375b8e31b9575a0ecc834c602657a9a9 testing commit 397a88b2cc869c823bf40bc403d36a62afec1edd compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ae3ac2d9062dbd5c172f07cf9d968faa3db516b04b151d634810f6d77fdf5cf1 run #0: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #1: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #2: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #3: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #4: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #5: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #6: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #7: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #8: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #9: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #10: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #11: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #12: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #13: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #14: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #15: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #16: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #17: crashed: SYZFAIL: netlink_send_ext: short netlink write run #18: crashed: SYZFAIL: netlink_send_ext: netlink read failed run #19: crashed: SYZFAIL: netlink_send_ext: netlink read failed testing current HEAD 4ba8e26127c393c32776dff6d79c5b82de6dc542 testing commit 4ba8e26127c393c32776dff6d79c5b82de6dc542 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 0fdb68c8d54f0f21df69c7031653a1f00295ca80855e1a53a3bb8a221968e46c all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 25m46.729513042s (build: 18m8.630808524s, test: 7m2.441833537s) the crash still happens on HEAD commit msg: Linux 4.14.262 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout 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: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout