diff options
authorAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>2018-09-04 15:45:59 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-09-04 16:45:02 -0700
commit464c7ffbcb164b2e5cebfa406b7fc6cdb7945344 (patch)
parent04b8e946075d4582093e84f54dc1a004b227794d (diff)
mm/hugetlb: filter out hugetlb pages if HUGEPAGE migration is not supported.
When scanning for movable pages, filter out Hugetlb pages if hugepage migration is not supported. Without this we hit infinte loop in __offline_pages() where we do pfn = scan_movable_pages(start_pfn, end_pfn); if (pfn) { /* We have movable pages */ ret = do_migrate_range(pfn, end_pfn); goto repeat; } Fix this by checking hugepage_migration_supported both in has_unmovable_pages which is the primary backoff mechanism for page offlining and for consistency reasons also into scan_movable_pages because it doesn't make any sense to return a pfn to non-migrateable huge page. This issue was revealed by, but not caused by 72b39cfc4d75 ("mm, memory_hotplug: do not fail offlining too early"). Link: http://lkml.kernel.org/r/20180824063314.21981-1-aneesh.kumar@linux.ibm.com Fixes: 72b39cfc4d75 ("mm, memory_hotplug: do not fail offlining too early") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reported-by: Haren Myneni <haren@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 files changed, 6 insertions, 1 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9eea6e809a4e..38d94b703e9d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1333,7 +1333,8 @@ static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
if (__PageMovable(page))
return pfn;
if (PageHuge(page)) {
- if (page_huge_active(page))
+ if (hugepage_migration_supported(page_hstate(page)) &&
+ page_huge_active(page))
return pfn;
pfn = round_up(pfn + 1,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 05e983f42316..89d2a2ab3fe6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7708,6 +7708,10 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
* handle each tail page individually in migration.
if (PageHuge(page)) {
+ if (!hugepage_migration_supported(page_hstate(page)))
+ goto unmovable;
iter = round_up(iter + 1, 1<<compound_order(page)) - 1;