bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on f54a5c0916af7d798b204eb70c484f154d69e0a3 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 7376fa4cb08bc92a3e50dc8017c1326a9cf648959206f03442d2a7732ca5fb9b all runs: crashed: WARNING: ODEBUG bug in pppol2tp_release testing current HEAD c01d4d1b885d96a7c8c27d629abeb918ca897dbe testing commit c01d4d1b885d96a7c8c27d629abeb918ca897dbe compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 89468ee5699aa67e886c007f8793fc59fa047cd9a92dfcd634e058f1f4e3f1d6 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m24.697580394s (build: 19m2.829665093s, test: 6m54.587010765s) the crash still happens on HEAD commit msg: Linux 4.14.257 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 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: hci1 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci1 command 0x040f 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: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout