bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on 77e2b66864e69c17416614228723a1ebd3581ddc testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: d20bb2b2be49ebbdb1e70ccbccb55e4efaaea7246e711ff8cdb81b35841c9ddf all runs: crashed: WARNING: ODEBUG bug in __cancel_work testing current HEAD 162b95d01320370b80cb2d5724cea4ae538ac740 testing commit 162b95d01320370b80cb2d5724cea4ae538ac740 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 74e2a3105b3826d309884aee52d07d1265c5080490c45cf26aa79d54163b2168 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 24m20.73483405s (build: 17m42.578623548s, test: 6m11.274649763s) the crash still happens on HEAD commit msg: Linux 4.14.244 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout