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Subject: Re: Boot failure on the powerstation with 2.6.30 latest
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
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> Actually, no, reverting that one doesn't fix it.
> 
> A full run of git bisect turns up this commit as the culprit; I'll make
> a fuss on lkml:

I haven't had the full log of that boot failure, but reverting the patch
Brian suggested won't work well indeed, as I said, from the moment slab
is initialized, page table allocations will use kmem caches which are
initialized by pgtable_cache_init().

So the problem does indeed seem to be another fallover of moving the
allocator initialization earlier.

I'm working from home today but I'll see if I can get somebody in the
office to wire up the powerstation (got disconnected for some reason
last week) for me so I can have a look.

The mutex issue Brian noticed will definitely break _any_ kmem_cache
operation anyway, so that's one bug that need fixing at least (well,
provided Brian analysis is right, I didn't have a chance to look myself
yet :-)

Cheers,
Ben.

> 83b519e8b9572c319c8e0c615ee5dd7272856090 is first bad commit
> commit 83b519e8b9572c319c8e0c615ee5dd7272856090
> Author: Pekka Enberg <penberg@cs.helsinki.fi>
> Date:   Wed Jun 10 19:40:04 2009 +0300
> 
>     slab: setup allocators earlier in the boot sequence
> 
> James
>