page-types: unsigned cannot be less than 0 in add_page()

If not signed, testing of the read() return value in this function
will not work.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c
index 59a4614f4b90..2279b616a7ac 100644
--- a/Documentation/vm/page-types.c
+++ b/Documentation/vm/page-types.c
@@ -560,7 +560,7 @@ static void walk_pfn(unsigned long voffset,
 {
         uint64_t buf[KPAGEFLAGS_BATCH];
         unsigned long batch;
-        unsigned long pages;
+        long pages;
         unsigned long i;
 
         while (count) {