bisecting fixing commit since 5b7a52cd2eef952cee8a72512ef370bcdef46636 building syzkaller on a1839e81524f4e427a4b57bca0e4633d459d3d18 testing commit 5b7a52cd2eef952cee8a72512ef370bcdef46636 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: aa9b195951927f413c1176ad6cc29156a442c54c2c13d3001f24e50621239ce8 all runs: crashed: KASAN: use-after-free Read in kvm_vm_ioctl_unregister_coalesced_mmio testing current HEAD 9dfbac0e6b8600043de8dc85ed072f5f1342dc15 testing commit 9dfbac0e6b8600043de8dc85ed072f5f1342dc15 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 73dfc1c57a1ebfb84a65467905b4c6fea18dce036a11761f4c130cf6a3b9fdf5 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 21m46.324678144s (build: 14m38.67415637s, test: 6m35.939992125s) the crash still happens on HEAD commit msg: Linux 4.14.258 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 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: hci2 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout