Re: [BUG] x86: bootmem broken on SGI UV

[Ingo Molnar <mingo@elte.hu>]

* Robin Holt <holt@sgi.com> wrote:

> On Sun, Oct 10, 2010 at 06:44:59AM -0500, Robin Holt wrote:
> > On Sun, Oct 10, 2010 at 12:43:19PM +0200, Ingo Molnar wrote:
> > > 
> > > * Ingo Molnar <mingo@elte.hu> wrote:
> > > 
> > > > 
> > > > * Robin Holt <holt@sgi.com> wrote:
> > > > 
> > > > > On Sat, Oct 09, 2010 at 07:59:45AM -0500, Russ Anderson wrote:
> > > > > > Yes, Yinghai's patch fixes the problem.
> > > > > > Thank you very much.
> > > > > 
> > > > > Will this be included in 2.6.36?  It is needed for boot in order for UV
> > > > > systems to boot.
> > > > 
> > > > -tip uses memblock APIs. If this happens with vanilla -git as well 
> > > > then we need a bootmem backport for the fix.
> > > 
> > > And to answer your question: yes, we can queue it up for -final as well 
> > > if it's a recent regression - 'doesnt boot at all' bugs are nasty. But 
> > > i'm not sure this is a bootmem problem so please double check vanilla 
> > > v2.6.36-rc7 as well.
> > 
> > The 36-rc7 kernel does not boot at all either.  I don't have any 
> > decent debug tools to dig in further.  It does fail on the same 
> > machine that Russ was testing with, but passes on any that have a 
> > single blade as the kernel Russ first identified as being a problem 
> > had.  Based upon my vague recollection of the boot messages, it 
> > appears to fail in a similar point in boot.  I would assume it is a 
> > similar problem.
> 
> 2.6.35 fails as well.  I will bisect for as long as time permits.

That's really bad. If this means that you have not booted vanilla 
mainline on UV in that timeframe _at all_, and that it was perma-broken 
since 2009 when that commit Yinghai identified went upstream, then 
there's little point in squeezing this fix into v2.6.36-final.

-rcs are strictly for regression fixes.

If you want upstream to care about you then you absolutely have the duty 
to at minimum test latest mainline ...

Thanks,

	Ingo