bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on f54a5c0916af7d798b204eb70c484f154d69e0a3 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ba3daa4ad74243f99e50d3d55165c913c255f75a6ab9175dd5d3b77934577f24 all runs: crashed: WARNING: suspicious RCU usage in tcp_disconnect testing current HEAD 8034e99d1a010a795b979582c0b2370584d8abf4 testing commit 8034e99d1a010a795b979582c0b2370584d8abf4 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b6219811505e0e0afb73edfc595271b0748465e0f540f380c3a08bc8f932f3f5 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 22m30.432692899s (build: 15m23.87918701s, test: 6m39.336445231s) the crash still happens on HEAD commit msg: Linux 4.14.266 crash: unregister_netdevice: waiting for DEV to become free can: request_module (can-proto-0) failed. can: request_module (can-proto-0) failed. unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout