[tom@localhost ~]$ sudo modprobe -r kvm_intel
[tom@localhost ~]$ sudo modprobe kvm_intel
[tom@localhost ~]$ ls -l /dev/kvm 
crw------- 1 root root 10, 232 Oct 24 13:15 /dev/kvm
[tom@localhost ~]$ sudo chmod 660 /dev/kvm 
[tom@localhost ~]$ qemu-system-x86_64 -enable-kvm

(process:1090): GLib-WARNING **: gmem.c:482: custom memory allocation vtable not supported
Could not access KVM kernel module: Permission denied
failed to initialize KVM: Permission denied
[tom@localhost ~]$ sudo chown root:libvirt /dev/kvm
[tom@localhost ~]$ qemu-system-x86_64 -enable-kvm

(process:1099): GLib-WARNING **: gmem.c:482: custom memory allocation vtable not supported
^Cqemu: terminating on signal 2
[tom@localhost ~]$ sudo chown root:tom /dev/kvm
[tom@localhost ~]$ qemu-system-x86_64 -enable-kvm

(process:1106): GLib-WARNING **: gmem.c:482: custom memory allocation vtable not supported
^Cqemu: terminating on signal 2