Created attachment 1890196 [details]
The qemu cmd line

Description of problem:
Guest can not boot up, VNC show info: Guest has not initialized the display (yet)

Version-Release number of selected component (if applicable):
libvirt-8.4.0-1.el9.x86_64
qemu-kvm-7.0.0-6.el9.x86_64
edk2-ovmf-20220526git16779ede2d36-1.el9.noarch

How reproducible:
100%

Steps to Reproduce:
1. Set a Q35+uefi guest with
1) 1 pcie-expander-bus, and 1 pcie-root-port connected to this expander bus;
2) guest has 13 pcie controller or more, for example:
<os>
    <type arch='x86_64' machine='pc-q35-rhel9.0.0'>hvm</type>
    <loader readonly='yes' secure='yes' type='pflash'>/usr/share/edk2/ovmf/OVMF_CODE.secboot.fd</loader>
  </os>
......
<controller type='pci' index='12' model='pcie-expander-bus'>
      <model name='pxb-pcie'/>
      <target busNr='254'/>
      <alias name='pci.12'/>
    </controller>
    <controller type='pci' index='13' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='13' port='0x0'/>
      <alias name='pci.13'/>
      <address type='pci' domain='0x0000' bus='0x0c' slot='0x00' function='0x0'/>
    </controller>

In this configuration, the guest has 13 pcie controllers in total. In which there is a pcie-expander-bus, and one pcie-root-port connected to it. 

2. Try to start the vm, it can not boot successfully, just show: 
Guest has not initialized the display (yet)

Actual results:
Guest can not boot successfully with msg "Guest has not initialized the display (yet)"

Expected results:
Guest boot up successfully

Additional info:
No such issue for guest with seabios