bisecting fixing commit since 2d2791fce891fc20709232d49a6bae075b9a77f8 building syzkaller on a57db36fe48aa500618c2eac3b38c27afe6d290f testing commit 2d2791fce891fc20709232d49a6bae075b9a77f8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 25898291f8031126576ce0cb39e204b5798165529fa4aa809675a2ab5cc26c14 all runs: crashed: KASAN: use-after-free Read in disk_unblock_events testing current HEAD 66722c42ec916e92cadda46316f8f6e3fdcaedc6 testing commit 66722c42ec916e92cadda46316f8f6e3fdcaedc6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 312b11a0e1bb76e2c708d82a5dcd33f3a9892df1c969ac37f7f3aa77c13cfff5 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 27m0.582934875s (build: 19m51.761035476s, test: 6m33.266794382s) the crash still happens on HEAD commit msg: Linux 4.14.256 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout