diff --git a/block/bio.c b/block/bio.c
index b2e0f0c94c5f71b526aa2a570f639b8d6d18fd00..cd0ca4166164c7f2edde7b08eeb88fbdeb427765 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -575,7 +575,8 @@ void bio_truncate(struct bio *bio, unsigned new_size)
 				offset = new_size - done;
 			else
 				offset = 0;
-			zero_user(bv.bv_page, offset, bv.bv_len - offset);
+			zero_user(bv.bv_page, bv.bv_offset + offset,
+				  bv.bv_len - offset);
 			truncated = true;
 		}
 		done += bv.bv_len;