DEBUG_PAGEALLOC is not compatible with hugetlb page support.  That debug
option turns off PSE.  Once it is turned off in CR4, the cpu will ignore
pse bit in the pmd and causing infinite page-not- present faults.

So disable DEBUG_PAGEALLOC if the user selected hugetlbfs.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>