bisecting fixing commit since 2b79150141611d3c6e1b55d4e70f49602482f0b8 building syzkaller on 18e33098d58c8738cc3b678346141b74d34d4e30 testing commit 2b79150141611d3c6e1b55d4e70f49602482f0b8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: d14012c606799418fede27a9aed2d60fad3b777ca192f50f0772ba8a7ea8932a all runs: crashed: kernel BUG in dnotify_free_mark testing current HEAD fa33f9094f36943ea32f7fbe323293b62e96151d testing commit fa33f9094f36943ea32f7fbe323293b62e96151d compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e151d55db665fa18671cba98ca86198132a8980cad2db7c99cceabefa31e879e all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 23m22.240953447s (build: 16m43.135920985s, test: 6m13.807823194s) the crash still happens on HEAD commit msg: Linux 4.14.268 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout