Re: regression fixed by using pci=rom

[Linus Torvalds <torvalds@linux-foundation.org>]

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.

So the reason I immediately reverted this is that it was simply totally 
wrong. If somebody cares about multi-node systems, the onus of making 
those work should be on *that*, not on old systems that already work.

Ingo, Thomas: I would _seriously_ suggest that you don't consider the x86 
PCI setup code to be "x86" code. Because it isn't. Not in that sense. Just 
don't take patches to it.

		Linus