Re: Slab panic on 2.6.19-rc3-git5 (-git4 was OK)

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

Andrew Morton wrote:
> On Sat, 28 Oct 2006 22:57:48 -0700
> "Martin J. Bligh" <mbligh@google.com> wrote:
> 
> 
>>-git4 was fine. -git5 is broken (on PPC64 blade)
>>
>>As -rc2-mm2 seemed fine on this box, I'm guessing it's something
>>that didn't go via Andrew ;-( Looks like it might be something
>>JFS or slab specific. Bigger PPC64 box with different config
>>was OK though.
>>
>>Full log is here: http://test.kernel.org/abat/59046/debug/console.log
>>Good -git4 run: http://test.kernel.org/abat/58997/debug/console.log
>>
>>kernel BUG in cache_grow at mm/slab.c:2705!
> 
> 
> This?
> 
> --- a/mm/vmalloc.c~__vmalloc_area_node-fix
> +++ a/mm/vmalloc.c
> @@ -428,7 +428,8 @@ void *__vmalloc_area_node(struct vm_stru
>  	area->nr_pages = nr_pages;
>  	/* Please note that the recursion is strictly bounded. */
>  	if (array_size > PAGE_SIZE) {
> -		pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node);
> +		pages = __vmalloc_node(array_size, gfp_mask & ~__GFP_HIGHMEM,
> +					PAGE_KERNEL, node);
>  		area->flags |= VM_VPAGES;
>  	} else {
>  		pages = kmalloc_node(array_size,

Don't you actually *want* the page array to be allocated from highmem? So the
gfp mask here should be just for whether we're allowed to sleep / reclaim (ie
gfp_mask & ~(__GFP_DMA|__GFP_DMA32) | (__GFP_HIGHMEM))?

Slab allocations should be (gfp_mask & ~(__GFP_DMA|__GFP_DMA32|__GFP_HIGHMEM)),
which you could mask in __get_vm_area_node

-- 
SUSE Labs, Novell Inc.
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