Re: regression fixed by using pci=rom

From: Jesse Barnes
Date: Fri May 09 2008 - 02:30:12 EST


On Thursday, May 08, 2008 6:46 pm Linus Torvalds wrote:
> On Thu, 8 May 2008, Jesse Barnes wrote:
> > Hm, yeah in many cases we definitely *do* want to try to get the
> > expansion ROM space allocated. But maybe it should be a lower priority
> > than other BARs... Gary?
>
> The thing is, a lot of these things have been done this way because not
> doing them that way breaks.
>
> We want to allocate expansion ROM space - even if we don't enable it -
> because not doing so will screw up bus sizing etc, and can make it
> impossible to allocate later.
>
> In general, changing PCI allocation strategy is really _really_ dangerous,
> even when it is "right", because it tends to expose a lot of issues where
> something worked just because it was perhaps indirectly causing a layout
> that worked.

Yeah, that was my first impression too, but the patch went upstream awhile ago
and I didn't see any background except for the changelog.

If anything, we should have a pci=norom option instead, so that big systems
that don't need the ROMs can use their address space more efficiently.

Jesse
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