Description of problem:
   Boot guest with gpxe in boot menu(F12), KVM cann't read hard disk correctly at the first time booting, after guest reboot (the second time) automatically, it then can boot from hard disk successfully.

Version-Release number of selected component (if applicable):
host info:
# uname -r && rpm -q kvm
2.6.18-333.el5
kvm-83-258.el5
# rpm -qa | grep  gpxe
gpxe-roms-qemu-0.9.7-9.el5
guest info:
# uname -r
2.6.18-333.el5

How reproducible:
almost every time

Steps to Reproduce:
1.prepare image installed with rhel5.9 64bit guest.
2.# alternatives --config qemu-pxe-roms

There are 2 programs which provide 'qemu-pxe-roms'.

  Selection    Command
-----------------------------------------------
*  1           /usr/share/etherboot
 + 2           /usr/share/gpxe

Enter to keep the current selection[+], or type selection number: 2
3.boot rhel 5.9 64bit guest.
eg: # /usr/libexec/qemu-kvm -m 2G -smp 2,cores=2,threads=1,sockets=1 -M rhel5.6.0 -cpu qemu64,+sse2 -name virtio_nic_test -drive file=/home/RHEL-Server-5.9-64-virtio.qcow2,format=qcow2,media=disk,if=virtio,cache=none,werror=stop,boot=on -uuid `uuidgen` -balloon virtio -monitor unix:/tmp/virt-nic-sluo,server,nowait -spice port=5931,disable-ticketing -qxl 1 -usbdevice tablet -soundhw ac97 -no-hpet -rtc-td-hack -no-kvm-pit-reinjection -monitor stdio -boot nc -net nic,vlan=0,model=virtio,macaddr=08:2E:5F:0A:0D:1B -net tap,sndbuf=0,vlan=0,script=/etc/qemu-ifup,downscript=no
4.press F12 and select "Network [gPXE (PCI 00:00.0)]" from boot menu.
  
Actual results:
after the step 4, guest fail to boot from hard disk at the first time with gpxe, it will reboot automatically. after rebooting, it then can boot from hard disk successfully.

Expected results:
guest should read hard disk correctly at the first time booting.

Additional info: