Re: 2.6.23-rc6-mm1 panic (memory controller issue ?)

[Balbir Singh <balbir@linux.vnet.ibm.com>]

Christoph Lameter wrote:
> On Wed, 19 Sep 2007, Balbir Singh wrote:
> 
>> Yes, the whole code is very interesting. From add_to_page_cache()
>> we call radix_tree_preload with __GFP_HIGHMEM cleared, but
>> from __add_to_swap_cache(), we don't make any changes to the
>> gfp_mask. radix_tree_preload() calls kmem_cache_alloc() and in slub
>> there is a check
>>
>>         BUG_ON(flags & GFP_SLAB_BUG_MASK);
>>
>> So, I guess all our allocations should check against __GFP_DMA and
>> __GFP_HIGHMEM. I'll review the code, test it and send a fix.
> 
> You need to use the proper mask from include/linux/gfp.h. Masking 
> individual bits will create problems when we create new bits.
> 

I agree 100%, that's why I want to review the code. I want to use
a mask that clears the GFP_SLAB_BUG_MASK bits and review it. I want
to check against other call sites that use gfp_mask as well.

-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL