Re: [PATCH 6/9] vfio/igd: Enable OpRegion by default

["Corvin Köhne" <C.Koehne@beckhoff.com>]

[-- Attachment #1: Type: text/plain, Size: 2636 bytes --]

On Tue, 2025-04-29 at 00:10 +0800, Tomita Moeko wrote:
> CAUTION: External Email!!
> As the presence of OpRegion is used to detect IGD device now, and
> guest driver usually depends on OpRegion to work. Enable OpRegion
> on IGD devices by default for out-of-the-box passthrough experience
> (except pre-boot display output), especially for libvirt users.
> 
> Example of IGD passthrough with libvirt:
> <hostdev mode="subsystem" type="pci" managed="yes">
>   <source>
>     <address domain="0x0000" bus="0x00" slot="0x02" function="0x0"/>
>   </source>
>   <rom file="/path/to/igd/rom"/>
>   <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x0"/>
>  </hostdev>
> 
> Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
> ---
>  docs/igd-assign.txt | 4 ++--
>  hw/vfio/pci.c       | 2 +-
>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/docs/igd-assign.txt b/docs/igd-assign.txt
> index 95beb76812..fc444503ff 100644
> --- a/docs/igd-assign.txt
> +++ b/docs/igd-assign.txt
> @@ -102,7 +102,7 @@ digital formats work well.
>  
>  Options
>  =======
> -* x-igd-opregion=[on|*off*]
> +* x-igd-opregion=[*on*|off]
>    Copy host IGD OpRegion and expose it to guest with fw_cfg
>  
>  * x-igd-lpc=[on|*off*]
> @@ -124,7 +124,7 @@ Examples
>  
>  * Adding IGD with OpRegion and LPC ID hack, but without VGA ranges
>    (For UEFI guests)
> -  -device vfio-pci,host=00:02.0,id=hostdev0,addr=2.0,x-igd-legacy-mode=off,x-
> igd-opregion=on,x-igd-lpc=on,romfile=efi_oprom.rom
> +  -device vfio-pci,host=00:02.0,id=hostdev0,addr=2.0,x-igd-legacy-mode=off,x-
> igd-lpc=on,romfile=efi_oprom.rom
>  
>  
>  Guest firmware
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 05a7a62204..38ff231625 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -3361,7 +3361,7 @@ static const Property vfio_pci_dev_properties[] = {
>      DEFINE_PROP_BIT("x-req", VFIOPCIDevice, features,
>                      VFIO_FEATURE_ENABLE_REQ_BIT, true),
>      DEFINE_PROP_BIT("x-igd-opregion", VFIOPCIDevice, features,
> -                    VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, false),
> +                    VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, true),
>      DEFINE_PROP_BIT("x-igd-lpc", VFIOPCIDevice, features,
>                      VFIO_FEATURE_ENABLE_IGD_LPC_BIT, false),
>      DEFINE_PROP_ON_OFF_AUTO("x-igd-legacy-mode", VFIOPCIDevice,

Reviewed-by: Corvin Köhne <c.koehne@beckhoff.com>


-- 
Kind regards,
Corvin

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 833 bytes --]