On a Thursday in 2021, Daniel P. Berrangé wrote:
>The <bios useserial='yes'> config results in use of the '-device sga'
>QEMU options. This in turn causes QEMU go load the sgabios.bin option
>ROM, which contains x86 machine code. This cannot work on non-x86
>arches, thus we should block the bad config.
>
>Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
>---
> src/qemu/qemu_validate.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
>diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c
>index d8f39b6bdd..3789361b57 100644
>--- a/src/qemu/qemu_validate.c
>+++ b/src/qemu/qemu_validate.c
>@@ -1194,6 +1194,14 @@ qemuValidateDomainDef(const virDomainDef *def,
>
> /* Serial graphics adapter */
> if (def->os.bios.useserial == VIR_TRISTATE_BOOL_YES) {
>+ /* -device sga is only sane on x86, since the option ROM it
>+ * loads contains x86 machine code.
>+ */
QEMU_CAPS_SGA is only set on x86 QEMUs, so we have already prevented this
config in the past.
But in context of patch 3/4, adding this check makes sense.
>+ if (!ARCH_IS_X86(def->os.arch)) {
>+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>+ _("BIOS serial console only supported on x86 architectures"));
>+ return -1;
>+ }
> if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_SGA)) {
> virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> _("qemu does not support SGA"));
>--
>2.31.1
>