On Tue, Nov 18, 2025 at 02:37:57AM +0000, Kazuhiro Abe (Fujitsu) wrote:
> > To clarify, the dependency on UEFI for ACPI is correct, at least to the
> > best of my
> > knowledge. The problem is that libvirt doesn't realize that edk2 loaded via
> > -bios is
> > still UEFI, so the check fails.
> >
> > For this specific case, it would probably be enough to ensure that the edk2
> > package installs a firmware descriptor along the lines of
> >
> > {
> > "interface-types": [
> > "uefi"
> > ],
> > "mapping": {
> > "device": "memory",
> > "filename": "/usr/share/qemu-efi-aarch64/QEMU_EFI.fd"
> > },
> > "targets": [
> > {
> > "architecture": "aarch64",
> > "machines": [
> > "virt-*"
> > ]
> > }
> > ]
> > }
> >
> > This should allow libvirt to automatically set <os firmware='efi'>, at
> > which point
> > the check will pass. This is exactly what happens for e.g. the SEV-SNP
> > firmware
> > builds.
> >
> > Note that I haven't actually tried the above, so there might be other
> > lingering
> > issues that I'm not aware of. I am currently working on some changes of my
> > own in
> > the area in order to enable the uefi-vars QEMU devices, which also expect
> > edk2 to
> > be loaded via -bios; so if there is anything else missing, I expect that I
> > will run into
> > it and fix it shortly.
>
> I understand your suggested approach.
> My understanding is that this is the case where autoselection is enabled and
> the JSON file in /usr/share/qemu/firmware is referenced.
>
> In a CCA environment, I think the common approach is to enable autoselection
> and reference the JSON file in /usr/share/qemu/firmware.
> However, there are cases where autoselection is disabled, such as when using
> <os> <loader type='rom'>, the JSON file will not be referenced.
> In such scenarios, your proposed method fails to allow libvirt to
> automatically set <os firmware='efi'>, and the issue still persists.
You've just identified one of those issues that I predicted I would
run into and have to fix :)
I already have a patch addressing that, among other things, in my
local branch. I expect to be able to post the whole series shortly,
probably next week.
--
Andrea Bolognani / Red Hat / Virtualization
