[Bug 87891] New: kernel BUG at mm/slab.c:2625!

[Andrew Morton]

On Tue, 11 Nov 2014 18:36:28 -0600 (CST) Christoph Lameter <cl at linux.com> wrote:

> On Tue, 11 Nov 2014, Andrew Morton wrote:
> 
> > There's no point in doing
> >
> > 	#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
> >
> > because __GFP_DMA32|__GFP_HIGHMEM are already part of ~__GFP_BITS_MASK.
> 
> ?? ~__GFP_BITS_MASK means bits 25 to 31 are set.
> 
> __GFP_DMA32 is bit 2 and __GFP_HIGHMEM is bit 1.

Ah, yes, OK.

I suppose it's possible that __GFP_HIGHMEM was set.

do_huge_pmd_anonymous_page
->pte_alloc_one
  ->alloc_pages(__userpte_alloc_gfp==__GFP_HIGHMEM)

but I haven't traced that through and that's 32-bit.

But anyway - Luke, please attach your .config to
https://bugzilla.kernel.org/show_bug.cgi?id=87891?