bisecting fixing commit since 2d2791fce891fc20709232d49a6bae075b9a77f8 building syzkaller on a57db36fe48aa500618c2eac3b38c27afe6d290f testing commit 2d2791fce891fc20709232d49a6bae075b9a77f8 with gcc (GCC) 8.4.1 20210217 kernel signature: 7b487a9004e807d2b361de2601a698e45b9a67d12ff64681341bbc4cbbba1c4f all runs: crashed: KASAN: use-after-free Read in disk_unblock_events testing current HEAD ad8397a84e1e425e3f8221638cee2bfa237d9b2c testing commit ad8397a84e1e425e3f8221638cee2bfa237d9b2c with gcc (GCC) 8.4.1 20210217 kernel signature: 3fc5aacf7f216d0529c89347d8d3eb4c9687ac841643cf4809db547d42038a10 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m20.796834239s (build: 19m37.174653688s, test: 6m17.490671401s) the crash still happens on HEAD commit msg: Linux 4.14.234 crash: unregister_netdevice: waiting for DEV to become free can: request_module (can-proto-0) failed. can: request_module (can-proto-0) failed. unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout