bisecting fixing commit since 958e517f4e16952e9a2e2d58fd32d28ae4e23dda building syzkaller on 6a81331a1d4c744da9204d02ec88d558f7eea9c9 testing commit 958e517f4e16952e9a2e2d58fd32d28ae4e23dda compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: d74955b5f6defb63a14b1db2f62e30357af9725a03357c5b3ff4fa22bfde6c94 run #0: OK run #1: crashed: KASAN: use-after-free Read in __queue_work run #2: crashed: WARNING: ODEBUG bug in bt_host_release run #3: crashed: KASAN: use-after-free Read in __queue_work run #4: crashed: WARNING: ODEBUG bug in bt_host_release run #5: crashed: KASAN: use-after-free Read in __queue_work run #6: crashed: WARNING: ODEBUG bug in bt_host_release run #7: crashed: KASAN: use-after-free Read in __queue_work run #8: OK run #9: OK run #10: OK run #11: OK 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 b8f3be299d5176348b15cc59d55b85faa3dece68 testing commit b8f3be299d5176348b15cc59d55b85faa3dece68 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 2bf4a6ed84a5a782a7bd835adeaf09df911f84a044229c66dbe391c1aad64d0b all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 28m29.420147672s (build: 14m53.869202403s, test: 12m56.369290512s) the crash still happens on HEAD commit msg: Linux 4.14.282 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout