bisecting fixing commit since 8961076ed318dfd22aa357b41589f07bf67e73b6 building syzkaller on 0767f13fbd87c99aea7893eb64199b76be42cd61 testing commit 8961076ed318dfd22aa357b41589f07bf67e73b6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 4319d77d3355a4071ad3809b4cf031d353551fc69eb36ca578899e178b2c2979 run #0: crashed: possible deadlock in kcm_ioctl run #1: crashed: possible deadlock in strp_sock_lock run #2: crashed: possible deadlock in strp_sock_lock run #3: crashed: possible deadlock in kcm_ioctl run #4: crashed: possible deadlock in strp_sock_lock run #5: crashed: possible deadlock in kcm_ioctl run #6: crashed: possible deadlock in strp_sock_lock run #7: crashed: possible deadlock in kcm_ioctl run #8: crashed: possible deadlock in strp_sock_lock run #9: crashed: possible deadlock in kcm_ioctl run #10: crashed: possible deadlock in kcm_ioctl run #11: crashed: possible deadlock in strp_sock_lock run #12: crashed: possible deadlock in kcm_ioctl run #13: crashed: possible deadlock in kcm_ioctl run #14: crashed: possible deadlock in kcm_ioctl run #15: crashed: possible deadlock in strp_sock_lock run #16: crashed: possible deadlock in strp_sock_lock run #17: crashed: possible deadlock in kcm_ioctl run #18: crashed: possible deadlock in strp_sock_lock run #19: crashed: possible deadlock in kcm_ioctl testing current HEAD cd529693461026636f76d0395a42cb2439bbd368 testing commit cd529693461026636f76d0395a42cb2439bbd368 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 2c95a9214d64a9c5c9d7ff6db5a1930c006cdb142b56fcb4564b396fd92073cb all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 22m32.553526685s (build: 15m3.568609986s, test: 6m43.175851196s) the crash still happens on HEAD commit msg: Linux 4.14.253 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout