Re: [PATCH 1/2] x86/efi: Map EFI memmap entries in-order at runtime

[Ingo Molnar]

* Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote:

> On Sun, Sep 27, 2015 at 09:30:48AM -0700, Andy Lutomirski wrote:
> > On Sep 26, 2015 1:19 PM, "H. Peter Anvin" <hpa@xxxxxxxxx> wrote:
> > >
> > > Sadly a lot of firmware is known to fail in that configuration :(  That was very much our guest choice.
> > >
> > 
> > Why can't we map everything completely 1:1 (VA = PA) and call the
> > setVA thing but pass it literally the identity.
> 
> Last time I tried this I found that some firmware makes assumptions 
> about having high addresses.

So the question is, what does Windows do?

PC firmware is a hostile environment for Linux, to be compatible the best we can 
do is to mimic the environment that the firmware is tested under - i.e. try to use 
the firmware in the way Windows uses it.

Thanks,

	Ingo
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