On Wed, Jan 19, 2022 at 12:30:04PM -0800, Lucas De Marchi wrote:
On Tue, Jan 18, 2022 at 02:01:45PM -0600, Bjorn Helgaas wrote:
Haha :) I was hoping not to touch it myself because I think this whole stolen memory thing is kind of nasty. It's not clear to me why we need it at all, or why we have to keep all this device-specific logic in the kernel, or why it has to be an early quirk as opposed to a regular PCI quirk. We had a thread [1] about it a while ago but I don't think anything got resolved.
I was reading that thread again and thinking what we could do to try to resolve this. I will reply on that thread.
Great! I hope there's some way around this.
But to try to make forward progress, I applied patch 1/5 (actually, the updated one from [2]) to my pci/misc branch with the updated commit log and code comments below.
thanks. I found the wording in the title odd as when I read "first" it gives me the impression it's saying there could be more, which is not possible.
I said "first integrated GPU" because Linux doesn't control what devices are in the system; it just has to deal with whatever it finds. All one can tell from the code is that if we find one or more devices that appear in intel_early_ids[], we reserve stolen memory for the first such device.
System-specific knowledge might tell you that there should only be one integrated GPU, but there's no constraint like that in Linux.
Bjorn