[PATCH 4.13 17/27] mm/sparse.c: fix typo in online_mem_sections

[Greg Kroah-Hartman]

4.13-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Michal Hocko <mhocko@xxxxxxxx>

commit b4ccec41af82b5a5518c6534444412961894f07c upstream.

online_mem_sections() accidentally marks online only the first section
in the given range.  This is a typo which hasn't been noticed because I
haven't tested large 2GB blocks previously.  All users of
pfn_to_online_page would get confused on the the rest of the pfn range
in the block.

All we need to fix this is to use iterator (pfn) rather than start_pfn.

Link: http://lkml.kernel.org/r/20170904112210.3401-1-mhocko@xxxxxxxxxx
Fixes: 2d070eab2e82 ("mm: consider zone which is not fully populated to have holes")
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 mm/sparse.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -630,7 +630,7 @@ void online_mem_sections(unsigned long s
 	unsigned long pfn;
 
 	for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
-		unsigned long section_nr = pfn_to_section_nr(start_pfn);
+		unsigned long section_nr = pfn_to_section_nr(pfn);
 		struct mem_section *ms;
 
 		/* onlining code should never touch invalid ranges */