bisecting fixing commit since 6b6446efedb27c2766745a04f9b5d4449f51391d building syzkaller on cba33199be220cbf61f7c0c8223d88a25a913d6f testing commit 6b6446efedb27c2766745a04f9b5d4449f51391d compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 3aa1734a1c57d79679c4b621807f25ecaf4f95a1648d303d5a2d1f4ea91a7b25 run #0: crashed: possible deadlock in __get_super run #1: crashed: possible deadlock in __get_super run #2: crashed: possible deadlock in __get_super run #3: crashed: possible deadlock in __get_super run #4: crashed: possible deadlock in __get_super run #5: crashed: possible deadlock in __get_super run #6: crashed: possible deadlock in __get_super run #7: crashed: possible deadlock in __get_super run #8: crashed: possible deadlock in __get_super run #9: crashed: possible deadlock in __get_super run #10: crashed: possible deadlock in __get_super run #11: crashed: possible deadlock in __get_super run #12: crashed: INFO: task hung in __get_super run #13: crashed: INFO: task hung in blkdev_put run #14: crashed: INFO: task hung in blkdev_put run #15: crashed: INFO: task hung in blkdev_put run #16: crashed: INFO: task hung in blkdev_put run #17: crashed: INFO: task hung in blkdev_put run #18: crashed: INFO: task hung in lo_ioctl run #19: crashed: INFO: task hung in blkdev_put testing current HEAD f6b016a9d961296d2db609d0259654371625e22e testing commit f6b016a9d961296d2db609d0259654371625e22e compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 730deda16b286deadb6c726f3bfeef7c4b4fa0967dedb6e9b2dac370f75f9e85 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 26m10.661374724s (build: 15m45.324296196s, test: 10m0.194676785s) the crash still happens on HEAD commit msg: Linux 4.14.251 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 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: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 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: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout