bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on f54a5c0916af7d798b204eb70c484f154d69e0a3 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217 kernel signature: 89ac970c986ded6b00cc861fef03767873cf5ecbb80cbd0e9b6a38d0f3343632 all runs: crashed: WARNING: ODEBUG bug in pppol2tp_release testing current HEAD 3d3abdc8ebd3c3082e4398fc73ceb4c852b66e85 testing commit 3d3abdc8ebd3c3082e4398fc73ceb4c852b66e85 with gcc (GCC) 8.4.1 20210217 kernel signature: 1edfa95995b3a1c244df520f66c2d453e12e580d6ece48246679682113a5fe9c all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 23m33.487678076s (build: 15m9.844596577s, test: 8m3.71098182s) the crash still happens on HEAD commit msg: Linux 4.14.236 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout