bisecting fixing commit since 6b6446efedb27c2766745a04f9b5d4449f51391d building syzkaller on cba33199be220cbf61f7c0c8223d88a25a913d6f testing commit 6b6446efedb27c2766745a04f9b5d4449f51391d compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 48e39fa76fa5dfe5dcfd2a2e1b846023b6ca19ec30e644551d391b0e85dee6a4 run #0: crashed: possible deadlock in blkdev_put run #1: crashed: possible deadlock in blkdev_put run #2: crashed: possible deadlock in blkdev_put run #3: crashed: possible deadlock in __get_super run #4: crashed: possible deadlock in blkdev_put run #5: crashed: possible deadlock in __get_super run #6: crashed: possible deadlock in blkdev_put 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: possible deadlock in __get_super run #13: crashed: possible deadlock in __get_super run #14: crashed: possible deadlock in __get_super run #15: crashed: possible deadlock in __get_super run #16: crashed: possible deadlock in __get_super run #17: crashed: INFO: task hung in blkdev_put run #18: crashed: INFO: task hung in blkdev_put run #19: crashed: INFO: task hung in blkdev_put testing current HEAD 84bae26850e3b384a45f0f9a5f8b3b5983afacd8 testing commit 84bae26850e3b384a45f0f9a5f8b3b5983afacd8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 361b157ea5e61d458a9b06ebbda58b82ee4f840b70c289be720eefbf0d72c05d all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 31m30.290172363s (build: 20m49.714109105s, test: 10m12.318114187s) the crash still happens on HEAD commit msg: Linux 4.14.284 crash: unregister_netdevice: waiting for DEV to become free IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready Bluetooth: hci0 command 0x0409 tx timeout can: request_module (can-proto-0) failed. 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: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 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: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f 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 Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout