On 2020.09.30 00:10:38 +0800, Fred Gao wrote:
> Bypass the IGD initialization for Intel's dgfx devices with own expansion
> ROM and the host/LPC bridge config space are no longer accessed.
> 
> v2: simply test if discrete or integrated gfx device
>     with root bus. (Alex Williamson)
>

Patch title is somehow misleading that better change to what this one does
that skip VFIO IGD setup for Intel discrete graphics card.

With that,

Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>

> Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
> Cc: Xiong Zhang <xiong.y.zhang@intel.com>
> Cc: Hang Yuan <hang.yuan@linux.intel.com>
> Cc: Stuart Summers <stuart.summers@intel.com>
> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
> Signed-off-by: Fred Gao <fred.gao@intel.com>
> ---
>  drivers/vfio/pci/vfio_pci.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index f634c81998bb..9258ccfadb79 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -336,10 +336,11 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
>  	if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev))
>  		vdev->has_vga = true;
>  
> -
> +	/* Intel's dgfx should not appear on root bus */
>  	if (vfio_pci_is_vga(pdev) &&
>  	    pdev->vendor == PCI_VENDOR_ID_INTEL &&
> -	    IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
> +	    IS_ENABLED(CONFIG_VFIO_PCI_IGD) &&
> +	    pci_is_root_bus(pdev->bus)) {
>  		ret = vfio_pci_igd_init(vdev);
>  		if (ret) {
>  			pci_warn(pdev, "Failed to setup Intel IGD regions\n");
> -- 
> 2.24.1.1.gb6d4d82bd5
> 

-- 

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