Re: [PATCH V3 4/4] acpi, apei: use EFI memmap to map GHES memory

Matt Fleming
2015-06-23T09:50:45Z

On Mon, 22 Jun, at 06:11:31AM, Matt Fleming wrote:
>
> Right, but see my previous comment about x86 discarding a bunch of
> attributes for memory regions because the kernel "knows better".
>
> And in most places, yes, the kernel really does know better. But this
> APEI case is special because irrespective of what the kernel says we
> want to be compatible with the firmware's memory map.
>
> And we don't have an API for that.

Maybe what we want is a new PAGE_* protection that is compatible with
any firmware mappings? That'd be nice because we wouldn't have to
introduce a whole new API for this GHES case and ioremap_* could do
whatever it wanted under the hood.

Thougts?

--
Matt Fleming, Intel Open Source Technology Center