bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on f54a5c0916af7d798b204eb70c484f154d69e0a3 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 4260231579b68fbe6c97e3581b4c6575b7a53e4b16456705357c0ed29d175896 all runs: crashed: WARNING: ODEBUG bug in pppol2tp_release testing current HEAD ed99bf0e81b558df39f7db2fa96d0228be4198c6 testing commit ed99bf0e81b558df39f7db2fa96d0228be4198c6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e07ce7a11183cabe04ec00f36952d179269b815a3f2ed537db538239c88fa944 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m51.486121857s (build: 18m28.078691344s, test: 7m48.482313001s) the crash still happens on HEAD commit msg: Linux 4.14.250 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 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: hci5 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout