On Mon, 2022-09-19 at 06:42 +0200, Gerd Hoffmann wrote:
On Fri, Sep 16, 2022 at 10:02:17AM -0700, Adam Williamson wrote:
Hi Gerd!
I'm working on a patch to revise how openQA sets video devices in qemu.
In that context, a question: if we always want to specify a single
video device with `-device` (e.g. `-device VGA` or `-device virtio-
vga`), should we also specify `-vga none` to ensure qemu doesn't also
include another adapter as a default for the -vga arg?
Doesn't hurt to include it. In theory it should not be needed, qemu has
a list of vga devices and in case '-device $vga' is found on the command
line will turn off the default vga device automatically. In practice
there are qemu versions where this list is not complete, so it
sometimes doesn't work as intended.
Alternatively use '-nodefaults' which will disable all automatically
added devices (vga, nic, cdrom, ...).
Thanks Gerd!
So, I got around to testing this today, and found something
interesting. On ppc64le, adding `-vga none` seems to break things.
Booting a Fedora installer ISO, which should show the boot menu with a
60 second timeout then boot to the installer, if we run the VM with `-
vga std`, we see the bootloader. If we run it with `-device VGA` and no
`-vga` arg, we see the bootloader. But if we run qemu with `-vga none -
device VGA`, we don't see the bootloader. The system just sits at the
OFW init screen apparently forever (I thought it might actually be
running in the background and recover to anaconda after the 60 second
boot timeout, but it doesn't seem to).
Not sure what's going on there, but thought you might be interested.