bisecting fixing commit since 1752938529c614a8ed4432ecce6ebc95d3b87207 building syzkaller on c104d4a3bfc1f83e7ed33b4dca70e099402ce39f testing commit 1752938529c614a8ed4432ecce6ebc95d3b87207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ab6ac7c0a98aeb4566a768d530ccf425d9efcbd3ef8ee3f55e5362988c22e4ca all runs: crashed: INFO: task hung in sync_inodes_sb testing current HEAD 5f9f3b0057d5c5782985784ba0159b05b4083055 testing commit 5f9f3b0057d5c5782985784ba0159b05b4083055 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 9f636b70cd0fc74c0e6cb2de6b1071fd524c34cb7deed62b6de7589e1117f235 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 30m5.786751224s (build: 19m4.431271915s, test: 10m33.155327161s) the crash still happens on HEAD commit msg: Linux 4.14.255 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout