Re: [PATCH] nommu page refcount bug fixing

[Nick Piggin <nickpiggin@yahoo.com.au>]

Luke Yang wrote:
>>>NOMMU special-casing in page refcounting. As a temporary fix, what I
>>>think should happen is simply for all slab allocations to ask for
>>>__GFP_COMP pages.
>>>
>>>Could you check that fixes your problem?
>>
>>  It works.  What's your plan to modify nommu mm? I would like to
>>help. And I am also interested in implementing the "non-power-of-2"
>>allocator in 2.6.
>>

I'll get it up to date and send it over to you, offline. It
would be great if you could help.

>>  New patch:
> 

Acked-by: Nick Piggin <npiggin@suse.de>

I'll write a changelog for you:

***
The earlier patch to consolidate mmu and nommu page allocation
and refcounting by using compound pages for nommu allocations
had a bug: kmalloc slabs who's pages were initially allocated
by a non-__GFP_COMP allocator could be passed into mm/nommu.c
kmalloc allocations which really wanted __GFP_COMP underlying
pages.

Fix that by having nommu pass __GFP_COMP to all higher order
slab allocations
***

Sound OK? Can you do it next time? ;)

-- 
SUSE Labs, Novell Inc.
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