1 files changed, 16 insertions, 3 deletions

diff --git a/mm/madvise.c b/mm/madvise.c
index 21261ff0466f..fd70d6aabc3e 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -625,18 +625,26 @@ static int madvise_inject_error(int behavior,
 {
         struct page *page;
         struct zone *zone;
+        unsigned int order;
 
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
-        for (; start < end; start += PAGE_SIZE <<
-                                compound_order(compound_head(page))) {
+
+        for (; start < end; start += PAGE_SIZE << order) {
                 int ret;
 
                 ret = get_user_pages_fast(start, 1, 0, &page);
                 if (ret != 1)
                         return ret;
 
+                /*
+                 * When soft offlining hugepages, after migrating the page
+                 * we dissolve it, therefore in the second loop "page" will
+                 * no longer be a compound page, and order will be 0.
+                 */
+                order = compound_order(compound_head(page));
+
                 if (PageHWPoison(page)) {
                         put_page(page);
                         continue;
@@ -749,6 +757,9 @@ madvise_behavior_valid(int behavior)
  *  MADV_DONTFORK - omit this area from child's address space when forking:
  *              typically, to avoid COWing pages pinned by get_user_pages().
  *  MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking.
+ *  MADV_WIPEONFORK - present the child process with zero-filled memory in this
+ *              range after a fork.
+ *  MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK
  *  MADV_HWPOISON - trigger memory error handler as if the given memory range
  *              were corrupted by unrecoverable hardware memory failure.
  *  MADV_SOFT_OFFLINE - try to soft-offline the given range of memory.
@@ -769,7 +780,9 @@ madvise_behavior_valid(int behavior)
  *  zero    - success
  *  -EINVAL - start + len < 0, start is not page-aligned,
  *              "behavior" is not a valid value, or application
- *              is attempting to release locked or shared pages.
+ *              is attempting to release locked or shared pages,
+ *              or the specified address range includes file, Huge TLB,
+ *              MAP_SHARED or VMPFNMAP range.
  *  -ENOMEM - addresses in the specified range are not currently
  *              mapped, or are outside the AS of the process.
  *  -EIO    - an I/O error occurred while paging in data.