bisecting fixing commit since 2b79150141611d3c6e1b55d4e70f49602482f0b8 building syzkaller on 18e33098d58c8738cc3b678346141b74d34d4e30 testing commit 2b79150141611d3c6e1b55d4e70f49602482f0b8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: f1119d7511e8ef781a3b074b21001a2bbe88cdde488955f77a51b0ec95019492 all runs: crashed: kernel BUG in dnotify_free_mark testing current HEAD cd529693461026636f76d0395a42cb2439bbd368 testing commit cd529693461026636f76d0395a42cb2439bbd368 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ca20c3a9ecd7af0e1614827341b3a1028e7a3665e70b9ee5f6663cd41c8dc676 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 22m9.953540029s (build: 15m5.438784481s, test: 6m41.750065023s) the crash still happens on HEAD commit msg: Linux 4.14.253 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 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: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout