Restarted VM and then allowed Windows 7 to start normally. Was able to complete defrag C: /H /U /V /X in cmd dos box. Not reproducible. Any interesting comments regarding assertion? Same command line as before:
qemu-system-x86_64 -enable-kvm -cpu host -localtime -usb -boot c -drive \ file=win7.qcow2,if=ide,index=0,media=disk,format=qcow2,detect-zeroes=unmap,discard=unmap \ -usbdevice tablet -net nic,vlan=0,model=rtl8139 -net user,vlan=0 \ -soundhw ac97 -m 2047M
