bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on 77e2b66864e69c17416614228723a1ebd3581ddc testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ffc72f607445219c8737ba1e78299599edd8a41189b8b854d4780543656a21ab run #0: OK run #1: OK run #2: OK run #3: crashed: WARNING: ODEBUG bug in batadv_nc_mesh_free run #4: crashed: WARNING: ODEBUG bug in batadv_nc_mesh_free run #5: OK run #6: crashed: unregister_netdevice: waiting for DEV to become free run #7: crashed: WARNING: ODEBUG bug in batadv_nc_mesh_free run #8: OK run #9: OK run #10: crashed: WARNING: ODEBUG bug in batadv_nc_mesh_free run #11: OK run #12: crashed: WARNING: ODEBUG bug in batadv_nc_mesh_free run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing current HEAD 1ccc597f801cbecffcaed7f2d1f620ec48f6f8df testing commit 1ccc597f801cbecffcaed7f2d1f620ec48f6f8df compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 02a3fe93bef2ed2c8636e8cf5a2bcbf6961aa24d82f916576e933ab823fa0d61 all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 27m59.128919086s (build: 14m43.067703336s, test: 12m53.317687291s) the crash still happens on HEAD commit msg: Linux 4.14.283 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 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: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout