What were you trying to do that didn't work?

Define a guest with 16G huge page backed and disk cache is 'none', after start it, the guest could not boot up.

Please provide the package NVR for which the bug is seen:

# rpm -q libvirt qemu-kvm kernel-64k
libvirt-10.10.0-6.el9.aarch64
qemu-kvm-9.1.0-14.el9.aarch64
kernel-64k-5.14.0-567.el9.aarch64

How reproducible is this bug?:100%

Steps to reproduce

1. Mount hugetlbfs and restart virtqemud

# mkdir /dev/hugepages16G
# mount -t hugetlbfs -o pagesize=16G hugetlbfs /dev/hugepages16G
# systemctl restart virtqemud

2. Allocate 16G hugepage

# echo 2 > /sys/kernel/mm/hugepages/hugepages-16777216kB/nr_hugepages

3. Define a guest with 16G huge page backed and disk cache is 'none' as below xml config:

<memory unit='GiB'>16</memory>
  <currentMemory unit='GiB'>16</currentMemory>
  <vcpu placement='static'>4</vcpu>
  <memoryBacking>
    <hugepages>
      <page size="16" unit="G"/>
    </hugepages>
   </memoryBacking>

...

<disk type='file' device='disk'>
            <driver name='qemu' type='qcow2' cache='none' />
      <source file='/var/lib/libvirt/images/RHEL-9.6-aarch64-latest-kernel-64k.qcow2'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
    </disk>

3. Start the guest 

# virsh start vm1
Domain 'vm1' started

Expected results

The guest could boot up successfully

Actual results

The guest fails to boot up and below msg is shown:

BdsDxe: failed to load Boot0001 "UEFI Misc Device" from PciRoot(0x0)/Pci(0x1,0x3)

UEFI Interactive Shell v2.2
EDK II
UEFI v2.70 (EDK II, 0x00010000)
Mapping table
     BLK0: Alias(s):
          PciRoot(0x0)/Pci(0x1,0x3)/Pci(0x0,0x0)
     BLK1: Alias(s):
          PciRoot(0x0)/Pci(0x1,0x3)/Pci(0x0,0x0)/HD(1,GPT,6118D207-E42E-4689-80C6-8B8BB31FE8E5,0x800,0x12C000)
     BLK2: Alias(s):
          PciRoot(0x0)/Pci(0x1,0x3)/Pci(0x0,0x0)/HD(2,GPT,C9AC6F61-88BE-42DD-BB96-DC7B62583C15,0x12C800,0x200000)
     BLK3: Alias(s):
          PciRoot(0x0)/Pci(0x1,0x3)/Pci(0x0,0x0)/HD(3,GPT,EEE32533-C163-42CB-9E73-3D80070D3383,0x32C800,0x10D3000)

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Additional info:

1. Only 16G hugepage backed or only none cache mode couldn't reproduce this issue;

2. Other huge page like 512M, 2M together with none cache mode disk could not reproduce this issue;