mm: fix invalid node in alloc_migrate_target()

It is incorrect to use next_node to find a target node, it will return
MAX_NUMNODES or invalid node.  This will lead to crash in buddy system
allocation.

Fixes: c8721bbbdd ("mm: memory-hotplug: enable memory hotplug to handle hugepage")
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Laura Abbott" <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Xishi Qiu 2016-04-01 14:31:20 -07:00 committed by Linus Torvalds
parent 969e8d7e47
commit 6f25a14a70

View File

@ -289,11 +289,11 @@ struct page *alloc_migrate_target(struct page *page, unsigned long private,
* now as a simple work-around, we use the next node for destination.
*/
if (PageHuge(page)) {
nodemask_t src = nodemask_of_node(page_to_nid(page));
nodemask_t dst;
nodes_complement(dst, src);
int node = next_online_node(page_to_nid(page));
if (node == MAX_NUMNODES)
node = first_online_node;
return alloc_huge_page_node(page_hstate(compound_head(page)),
next_node(page_to_nid(page), dst));
node);
}
if (PageHighMem(page))