bisecting fixing commit since 2d2791fce891fc20709232d49a6bae075b9a77f8 building syzkaller on 52e3731913ab2677be27c29ed8142b04e8f28521 testing commit 2d2791fce891fc20709232d49a6bae075b9a77f8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: a5d210b016a1c51e60bc13b8a63f12a7e4039bf5151e2eca8906361c7dc9ab4d all runs: crashed: INFO: task hung in nbd_ioctl testing current HEAD eb045674aab31aa55a4f9aec27cce36e3d946a21 testing commit eb045674aab31aa55a4f9aec27cce36e3d946a21 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 3b2b79a1fe6be5d3224447def323ffe48b9dbc03d58aa9f17149092d23f912fa all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 31m44.019391485s (build: 21m10.48006871s, test: 9m44.5749912s) the crash still happens on HEAD commit msg: Linux 4.14.272 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout