mm/sparse.c: fix typo in online_mem_sections

BugLink: http://bugs.launchpad.net/bugs/1717549
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@kernel.org
Fixes: 2d070eab2e82 ("mm: consider zone which is not fully populated to have holes")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

diff --git a/mm/sparse.c b/mm/sparse.c
index 7b4be3fd5cac074177b7f17ebdeb12dfa56d22e5..cdce7a7bb3f353a4076e559b2162e8b0048875f0 100644 (file)
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -630,7 +630,7 @@ void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
        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 */