bisecting fixing commit since 7d7d1c0ab3eb7c8d8f63a126535018007823b207 building syzkaller on 8bdd5343e64460868dd1318257a39f1e7fd89471 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217 kernel signature: 9fc018f792dc2853db35a25ee79b326e2fe4069bcecf069c6df7efbdd18a4752 all runs: crashed: INFO: task hung in blkdev_put testing current HEAD 4e68c9b0763ff55eaa69d6e519f07515f1c9037b testing commit 4e68c9b0763ff55eaa69d6e519f07515f1c9037b with gcc (GCC) 8.4.1 20210217 kernel signature: 27e592cb32063634140f2d7beab3725a297a838cf43bf5ff7ff2b8b07de0c84d all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 25m8.695866196s (build: 14m37.376091842s, test: 10m9.170229506s) the crash still happens on HEAD commit msg: Linux 4.14.239 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: hci0 command 0x0409 tx timeout Bluetooth: hci5 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: hci5 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci5 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: hci5 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout