mm/memory-failure: fix race in counting num_poisoned_pages
mm/memory-failure: fix race in counting num_poisoned_pages

When memory_failure() is called on a page which are just freed after
page migration from soft offlining, the counter num_poisoned_pages is
raised twi= ce.  So let's fix it with using TestSetPageHWPoison.

Signed-off-by: Naoya Horiguchi <8e7a128cd0264d3269a891fb3e87507c2985f8af@ah.jp.nec.com>
Cc: Andi Kleen <dbd122ef7b6a09ffecf5db9c9296320f3c94e707@firstfloor.org>
Cc: Dean Nelson <d3465cf1d47044656beb99a21b027db731478f56@redhat.com>
Cc: Tony Luck <e7984595ec0368ff920a7b3521dc7093683f6f26@intel.com>
Cc: "Kirill A. Shutemov" <9b153e80bc985b32d577460a8a24e398d4182978@shutemov.name>
Cc: Hugh Dickins <d3abdf3e2800e6cb849f11b81e6eb50b34d96431@google.com>
Cc: David Rientjes <d8cd2994e15bc61ddb2b113030bda55eebc3a0fe@google.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs