Commit e558464b authored by Muchun Song's avatar Muchun Song Committed by Linus Torvalds
Browse files

mm: hugetlb: fix missing put_page in gather_surplus_pages() 

The VM_BUG_ON_PAGE avoids the generation of any code, even if that
expression has side-effects when !CONFIG_DEBUG_VM.

Link: https://lkml.kernel.org/r/20210126031009.96266-1-songmuchun@bytedance.com


Fixes: e5dfaceb ("mm/hugetlb.c: just use put_page_testzero() instead of page_count()")
Signed-off-by: default avatarMuchun Song <songmuchun@bytedance.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: default avatarMiaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 28abcc96

mm/hugetlb.c

+4 −1
Original line number Diff line number Diff line
@@ -2047,13 +2047,16 @@ static int gather_surplus_pages(struct hstate *h, long delta) 


	/* Free the needed pages to the hugetlb pool */

	list_for_each_entry_safe(page, tmp, &surplus_list, lru) {

		int zeroed;



		if ((--needed) < 0)

			break;

		/*

		 * This page is now managed by the hugetlb allocator and has

		 * no users -- drop the buddy allocator's reference.

		 */

		VM_BUG_ON_PAGE(!put_page_testzero(page), page);

		zeroed = put_page_testzero(page);

		VM_BUG_ON_PAGE(!zeroed, page);

		enqueue_huge_page(h, page);

	}

free: