memcg: bugfix for memory hotplug

The start pfn calculation in page_cgroup's memory hotplug notifier chain
is wrong.

Tested-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index f59d797dc5a9b28ddcb3eae0f0aeeb4bc6e6daad..1223d927904d196d652911e222bc4a50140c627b 100644 (file)
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -165,7 +165,7 @@ int online_page_cgroup(unsigned long start_pfn,
        unsigned long start, end, pfn;
        int fail = 0;
 
-       start = start_pfn & (PAGES_PER_SECTION - 1);
+       start = start_pfn & ~(PAGES_PER_SECTION - 1);
        end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
 
        for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) {
@@ -188,7 +188,7 @@ int offline_page_cgroup(unsigned long start_pfn,
 {
        unsigned long start, end, pfn;
 
-       start = start_pfn & (PAGES_PER_SECTION - 1);
+       start = start_pfn & ~(PAGES_PER_SECTION - 1);
        end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION);
 
        for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)