Commit d6692183 authored Mar 31, 2006 by Kenneth W Chen Committed by Linus Torvalds Mar 31, 2006

[PATCH] fix extra page ref count in follow_hugetlb_page



git-commit: d5d4b0aa
"[PATCH] optimize follow_hugetlb_page" breaks mlock on hugepage areas.

I mis-interpret pages argument and made get_page() unconditional.  It
should only get a ref count when "pages" argument is non-null.

Credit goes to Adam Litke who spotted the bug.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Acked-by: Adam Litke <agl@us.ibm.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 93fac704

mm/hugetlb.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -697,9 +697,10 @@ int follow_hugetlb_page(struct mm_struct mm, struct vm_area_struct vma,
		pfn_offset = (vaddr & ~HPAGE_MASK) >> PAGE_SHIFT;
		page = pte_page(*pte);
		same_page:
		if (pages) {
		get_page(page);
		if (pages)
		pages[i] = page + pfn_offset;
		}

		if (vmas)
		vmas[i] = vma;