Kernel panic due to page migration accessing memory holes

[Russell King - ARM Linux]

On Wed, Feb 17, 2010 at 04:45:54PM -0800, Michael Bohan wrote:
> I have encountered a kernel panic on the ARM/msm platform in the mm  
> migration code on 2.6.29.  My memory configuration has two discontiguous  
> banks per our ATAG definition.   These banks end up on addresses that  
> are 1 MB aligned.  I am using FLATMEM (not SPARSEMEM), but my  
> understanding is that SPARSEMEM should not be necessary to support this  
> configuration.  Please correct me if I'm wrong.

Make sure you have ARCH_HAS_HOLES_MEMORYMODEL enabled.