Re: regression fixed by using pci=rom

[Gary Hade <garyhade@us.ibm.com>]

On Thu, May 08, 2008 at 11:29:39PM -0700, Jesse Barnes wrote:
> 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.

This is actually the solution I was going to suggest.  I will 
work on it.

Gary

-- 
Gary Hade
System x Enablement
IBM Linux Technology Center
503-578-4503  IBM T/L: 775-4503
garyhade@us.ibm.com
http://www.ibm.com/linux/ltc