bisecting fixing commit since 2d2791fce891fc20709232d49a6bae075b9a77f8 building syzkaller on 52e3731913ab2677be27c29ed8142b04e8f28521 testing commit 2d2791fce891fc20709232d49a6bae075b9a77f8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: d96a134cd96cfd1892bd924669c60816ae2300d8eacd246f5a0aafc724172238 all runs: crashed: INFO: task hung in truncate_inode_pages_range testing current HEAD 15a1c6b6f5162f7b70cf9a77cd8ed9771c1f0b53 testing commit 15a1c6b6f5162f7b70cf9a77cd8ed9771c1f0b53 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 6c1b31d889765eb872368929f1ae43b5d433353ee05dd5132196534b10de7e12 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 33m23.967035679s (build: 20m35.814554594s, test: 12m20.258615966s) the crash still happens on HEAD commit msg: Linux 4.14.276 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 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: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout