On Tue, Jul 18, 2023 at 06:14:00PM -0500, Bjorn Helgaas wrote: > On Fri, Jun 30, 2023 at 06:17:29PM +0800, Sui Jingfeng wrote: > > From: Sui Jingfeng <suijingfeng@xxxxxxxxxxx> > > > > VGAARB should only care about PCI VGA class devices (pdev->class == 0x0300) > > since only those devices might have VGA routed to them. > > This is not actually a question of whether VGA addresses (mem > 0xa0000-0xbffff and io 0x3b0-0x3bb, 0x3c0-0x3df) might be *routed* to > the device because that routing is controlled by the bridge VGA Enable > bit, not by a device Class Code. > > I think the important question here is what devices will *respond* to > those VGA addresses. The VGA arbiter works by managing bridge VGA > Enable bits, so if we know a device doesn't respond to the VGA > addresses, there's no point in adding a vga_device for it. Sorry, I see that I replied to an old version of this patch. I'll go look at this series instead: https://lore.kernel.org/r/20230711134354.755966-1-sui.jingfeng@xxxxxxxxx Bjorn
