diff --git a/src/drivers/infiniband/hermon.c b/src/drivers/infiniband/hermon.c
index 3797d96e..a1d2a3bd 100644
--- a/src/drivers/infiniband/hermon.c
+++ b/src/drivers/infiniband/hermon.c
@@ -2113,6 +2113,7 @@ static int hermon_map_vpm ( struct hermon *hermon,
 	assert ( ( va & ( HERMON_PAGE_SIZE - 1 ) ) == 0 );
 	assert ( ( pa & ( HERMON_PAGE_SIZE - 1 ) ) == 0 );
 	assert ( ( len & ( HERMON_PAGE_SIZE - 1 ) ) == 0 );
+	assert ( len != 0 );
 
 	/* Calculate starting points */
 	start = pa;