bisecting fixing commit since 397a88b2cc869c823bf40bc403d36a62afec1edd building syzkaller on e4b4d570a88c0d2e0420c6e21fc20d90564636b1 testing commit 397a88b2cc869c823bf40bc403d36a62afec1edd compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: da9d2b4b44a292e4994181c4828714611357c2ccf0048710872f6f220b0c4b45 run #0: crashed: KASAN: use-after-free Read in rht_deferred_worker run #1: crashed: KASAN: use-after-free Read in rht_deferred_worker run #2: crashed: KASAN: use-after-free Read in rht_deferred_worker run #3: crashed: KASAN: use-after-free Read in rht_deferred_worker run #4: crashed: KASAN: use-after-free Read in rht_deferred_worker run #5: crashed: KASAN: use-after-free Read in rht_deferred_worker run #6: crashed: KASAN: use-after-free Read in rht_deferred_worker run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: crashed: KASAN: use-after-free Read in rht_deferred_worker run #15: crashed: KASAN: use-after-free Read in rht_deferred_worker run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing current HEAD e853993d29aa42ac4b3c2912db975a0a66d7a5b0 testing commit e853993d29aa42ac4b3c2912db975a0a66d7a5b0 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 546da9a3bae1f3be591f59242d672696db6492acd1ac885d16fc28edd27205c4 all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 33m44.356660516s (build: 17m51.332103378s, test: 15m19.675177216s) the crash still happens on HEAD commit msg: Linux 4.14.269 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: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout