Is my VM using KVM or QEMU?

Because kvm builds on top of QEMU, it's just a hw acceleration.

With this you can see that the actual process running your VM is a kvm process.

ps xa| grep "[b]in/kvm"

http://en.wikipedia.org/wiki/Kernel-based_Virtual_Machine#Design

By itself, KVM does not perform any emulation. Instead, a user-space program uses the /dev/kvm interface to set up the guest VM's address space, feeds it simulated I/O and maps its video display back onto the host's. QEMU versions 0.10.0 and later make use of this.