On Mon, 17 Sep 2018 08:17:29 +0200
Gerd Hoffmann <kra...@redhat.com> wrote:
> So we have a boot display when using a vgpu as primary display.
>
> ramfb depends on a fw_cfg file. fw_cfg files can not be added and
> removed at runtime, therefore a ramfb-enabled vfio device can't be
> hotplugged.
>
> Add a nohotplug variant of the vfio-pci device (as child class). Add
> the ramfb property to the nohotplug variant only. So to enable the vgpu
> display with boot support use this:
>
> -device vfio-pci-nohotplug,display=on,ramfb=on,sysfsdev=...
>
> Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> ---
> hw/vfio/pci.h | 1 +
> include/hw/vfio/vfio-common.h | 2 ++
> hw/vfio/display.c | 12 ++++++++++++
> hw/vfio/pci.c | 25 +++++++++++++++++++++++++
> 4 files changed, 40 insertions(+)
>
> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
> index 52b065421a..904e286586 100644
> --- a/hw/vfio/pci.h
> +++ b/hw/vfio/pci.h
> @@ -149,6 +149,7 @@ typedef struct VFIOPCIDevice {
> #define VFIO_FEATURE_ENABLE_IGD_OPREGION \
> (1 << VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT)
> OnOffAuto display;
> + bool enable_ramfb;
> int32_t bootindex;
> uint32_t igd_gms;
> OffAutoPCIBAR msix_relo;
Hi Gerd,
One tiny nit here, we can move this new bool down in the struct with
the rest of the bools for better alignment. I can change that on
commit. However, I'm not having luck getting ramfb to work; the
display is only getting initialized once the guest driver loads. This
is a 440FX/SeaBIOS VM, it looks like you've already updated bios.bin in
qemu.git with ramfb support, but I also see the same results with
bios.bin from your seabios.git package. I'm using libvirt to launch
the guest with a wrapper around qemu-system-x86_64 to replace vfio-pci
with vfio-pci-nohotplug, resulting in a command line including:
-bios /usr/share/seabios.git/bios.bin \
-spice
port=0,disable-ticketing,gl=on,rendernode=/dev/dri/by-path/pci-0000:00:02.0-render,seamless-migration=on
\
-device
vfio-pci-nohotplug,id=hostdev0,sysfsdev=...,display=on,bus=pci.0,addr=0x9 \
-set device.hostdev0.x-igd-opregion=on \
-set device.hostdev0.ramfb=on \
Relevant XML blobs:
<graphics type='spice'>
<listen type='none'/>
<gl enable='yes' rendernode='/dev/dri/by-path/pci-0000:00:02.0-render'/>
</graphics>
<video>
<model type='none'/>
</video>
<hostdev mode='subsystem' type='mdev' managed='no' model='vfio-pci'
display='on'>
<source>
<address uuid='cd4fa69f-c24c-476f-a61d-abca705e2a13'/>
</source>
<address type='pci' domain='0x0000' bus='0x00' slot='0x09'
function='0x0'/>
</hostdev>
...
<qemu:commandline>
<qemu:arg value='-set'/>
<qemu:arg value='device.hostdev0.x-igd-opregion=on'/>
<qemu:arg value='-set'/>
<qemu:arg value='device.hostdev0.ramfb=on'/>
</qemu:commandline>
This is a Windows 10 VM, but as I understand this ramfb support, I
think I'm still supposed to see SeaBIOS boot messages and perhaps even
the Windows boot animation before the guest driver takes over, is that
correct? What am I missing? Thanks,
Alex
