bisecting fixing commit since 756db2ba8bde4ead58ceb54e9cbc71f526f9a98f building syzkaller on 838e7e2cd9228583ca33c49a39aea4d863d3e36d testing commit 756db2ba8bde4ead58ceb54e9cbc71f526f9a98f compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 5c3bdd4a961554000a973d43fd2fbb3d41b40f5747055108f61cc90ecd62efbc all runs: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD c01d4d1b885d96a7c8c27d629abeb918ca897dbe testing commit c01d4d1b885d96a7c8c27d629abeb918ca897dbe compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 5f6893c5eeb252d314d231b34ab19e66f7bb0a755772c427383d0e67722bf665 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 23m10.333893059s (build: 16m9.761906631s, test: 6m27.93359828s) the crash still happens on HEAD commit msg: Linux 4.14.257 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout