1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/timex.h b/include/linux/timex.h
index 998a55d80acf..aa3475fcff64 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -190,7 +190,7 @@ struct timex {
  * offset and maximum frequency tolerance.
  */
 #define SHIFT_USEC 16           /* frequency offset scale (shift) */
-#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
+#define PPM_SCALE ((s64)NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
 #define PPM_SCALE_INV_SHIFT 19
 #define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
                        PPM_SCALE + 1)