bisecting fixing commit since 1752938529c614a8ed4432ecce6ebc95d3b87207 building syzkaller on c104d4a3bfc1f83e7ed33b4dca70e099402ce39f testing commit 1752938529c614a8ed4432ecce6ebc95d3b87207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b2dc63f4b861f68e22d8e301fe0bd2fdc46382be60b107dcdee060ef9ffec07f all runs: crashed: INFO: task hung in sync_inodes_sb testing current HEAD a35d65bedfbc38cffe2701798cd6810bbdf07892 testing commit a35d65bedfbc38cffe2701798cd6810bbdf07892 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 00c39dc1b06a63a5f07fa12191660f1f5bbcdb577cd83a12d627fd8d99a6caac all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 27m4.768459554s (build: 16m27.153078572s, test: 10m8.596895609s) the crash still happens on HEAD commit msg: Linux 4.14.267 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout