Hi Daniel,
On a whim, I tried installing libvirt on a Raspberry Pi 5. I was
pleasantly surprised to find that it all worked, apart from one small
wrinkle.
I typically use virt-install and set up a serial console, but this
failed with the error:
ERROR unsupported configuration: BIOS serial console only supported
on x86 architectures
I created the VM with a graphical console then manually adjusted the
config afterwards to use a serial console and it all worked fine. After
a bit of digging I saw an email[1] from yourself talking about how
graphics=off has semantic effects beyond just controlling whether the
firmware prints to the serial or not. After a bit more digging, I
found out that Qemu 8.0[2] removed the sga device due to SeaBIOS 1.11.0
and newer supporting this feature natively when QEMU is started with the
option -M graphics=off.
I made the following small patch against the Debian package:
--- libvirt-11.3.0.orig/src/qemu/qemu_validate.c
+++ libvirt-11.3.0/src/qemu/qemu_validate.c
@@ -1304,15 +1304,7 @@ qemuValidateDomainDef(const virDomainDef
/* On x86 -machine graphics=off toggles the use of the
* serial console in SeaBIOS (and theoretically other
* firmwares).
- * On non-x86, it has also sorts of other effects
- * on QEMU device models created and so we don't
- * want to allow its use.
*/
- if (!ARCH_IS_X86(def->os.arch)) {
- virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
- _("BIOS serial console only supported on x86
architectures"));
- return -1;
- }
if (!def->nserials) {
virReportError(VIR_ERR_XML_ERROR, "%s",
_("need at least one serial port to use BIOS
serial output"));
With that change, I can now create VMs with a serial console through
virt-install on the Raspberry PI 5.
Have I got this right? If so, I'm happy to submit the patch.
Regards,
Leigh.
--
[1] https://mail.gnu.org/archive/html/qemu-devel/2021-09/msg02417.html
[2] https://wiki.qemu.org/ChangeLog/8.0
