Re: [PATCH] x86: split e820 reserved entries record to late

Linus Torvalds
2008-08-28T20:39:33Z

On Thu, 28 Aug 2008, H. Peter Anvin wrote:
>
> The sucky case, of course, would be an uninitialized BAR pointing
> into unusable address space which happens to be reserved in e820. This
> seems very difficult to disambiguate from the above case through any
> algorithm that I can think of.

Yeah, well, the good news is that it should be fairly rare. Any sane PCI
device will come out of reset with IO and MEM disabled, and even if some
crazy BIOS enables IO/MEM on it and activates the BAR's with some random
content, I'm not seeing how that would work well with Windows either if it
really was overlapping with some critical real other piece of hardware.

So I'd _assume_ that something like that would break Windows too, and thus
not actually make it into a real product.

Maybe.

Linus