mm/memory-failure.c: use compound_head() flags for huge pages

commit 7258ae5c5a upstream.

memory_failure() chooses a recovery action function based on the page
flags.  For huge pages it uses the tail page flags which don't have
anything interesting set, resulting in:

> Memory failure: 0x9be3b4: Unknown page state
> Memory failure: 0x9be3b4: recovery action for unknown page: Failed

Instead, save a copy of the head page's flags if this is a huge page,
this means if there are no relevant flags for this tail page, we use the
head pages flags instead.  This results in the me_huge_page() recovery
action being called:

> Memory failure: 0x9b7969: recovery action for huge page: Delayed

For hugepages that have not yet been allocated, this allows the hugepage
to be dequeued.

Fixes: 524fca1e73 ("HWPOISON: fix misjudgement of page_action() for errors on mlocked pages")
Link: http://lkml.kernel.org/r/20170524130204.21845-1-james.morse@arm.com
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
James Morse 2017-06-16 14:02:29 -07:00 committed by Greg Kroah-Hartman
parent 0c0d3d8730
commit 1419b87521

View File

@ -1176,7 +1176,10 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
* page_remove_rmap() in try_to_unmap_one(). So to determine page status
* correctly, we save a copy of the page flags at this time.
*/
page_flags = p->flags;
if (PageHuge(p))
page_flags = hpage->flags;
else
page_flags = p->flags;
/*
* unpoison always clear PG_hwpoison inside page lock