On Tue, Oct 02, 2012 at 05:59:11PM +0100, Will Deacon wrote:

On x86 memory accesses to pages without the ACCESSED flag set result in the
ACCESSED flag being set automatically. With the ARM architecture a page access
fault is raised instead (and it will continue to be raised until the ACCESSED
flag is set for the appropriate PTE/PMD).

For normal memory pages, handle_pte_fault will call pte_mkyoung (effectively
setting the ACCESSED flag). For transparent huge pages, pmd_mkyoung will only
be called for a write fault.

This patch ensures that faults on transparent hugepages which do not result
in a CoW update the access flags for the faulting pmd.

Cc: Andrea Arcangeli <redacted>
Cc: Chris Metcalf <redacted>
Signed-off-by: Steve Capper <redacted>
Signed-off-by: Will Deacon <redacted>

Acked-by: Kirill A. Shutemov <redacted>

-- 
 Kirill A. Shutemov