bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on f54a5c0916af7d798b204eb70c484f154d69e0a3 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 92a58754465cd045e24c191bfef16fa8c156bbc6ae0893ccec2331daaa5cf2f6 all runs: crashed: WARNING: ODEBUG bug in pppol2tp_release testing current HEAD 8034e99d1a010a795b979582c0b2370584d8abf4 testing commit 8034e99d1a010a795b979582c0b2370584d8abf4 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 6dd88b90d914305b52b8654d95cbe6bb79d1c011f8c69cb5067f436c12a56a84 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 30m56.648245012s (build: 23m18.149952017s, test: 7m2.245613687s) the crash still happens on HEAD commit msg: Linux 4.14.266 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout