Re: [libvirt] [PATCH 1/4] qemu: Advertise ACPI support for aarch64 guests

> +    /* Older QEMU versions reported -no-acpi in the output of -help even > +     * though it was not supported by the architecture. The issue has since > +     * been fixed, but to maintain compatibility with all release we still   "releases"

> +     * need to filter out the capability for architectures that we know > +     * don't support the feature, eg. anything but x86 and aarch64 */ > +    if (!ARCH_IS_X86(qemuCaps->arch) && > +        qemuCaps->arch != VIR_ARCH_AARCH64) { >          virQEMUCapsClear(qemuCaps, QEMU_CAPS_NO_ACPI); > +    }   Some day maybe we'll be able to stop parsing the help output. Still makes me wonder is AARCH64 even support on those older versions and thus is this necessary?  IDC either way as I suppose this is preventative or "more complete".

> @@ -4222,9 +4231,14 @@ virQEMUCapsInitArchQMPBasic(virQEMUCapsPtr qemuCaps, >          goto cleanup; >      } >   > -    /* ACPI/HPET/KVM PIT are x86 specific */ > -    if (ARCH_IS_X86(qemuCaps->arch)) { > +    /* ACPI only works on x86 and aarch64 */ > +    if (ARCH_IS_X86(qemuCaps->arch) || > +        qemuCaps->arch == VIR_ARCH_AARCH64) { >          virQEMUCapsSet(qemuCaps, QEMU_CAPS_NO_ACPI); > +    } > + > +    /* HPET and KVM PIT are x86 specific */ > +    if (ARCH_IS_X86(qemuCaps->arch)) { >          virQEMUCapsSet(qemuCaps, QEMU_CAPS_NO_HPET); >          virQEMUCapsSet(qemuCaps, QEMU_CAPS_NO_KVM_PIT); >      }   Considering on what's coming in patch 2, this would be better as a virQEMUCapsSetFirmwareCaps? "utility" function...  That way the added comments in both places referencing the other place could be dropped.