[arbel] Assert that mapping length is non-zero

An (impossible) mapping length of zero produces a negative bit shift,
which is technically undefined.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/infiniband/arbel.c b/src/drivers/infiniband/arbel.c
index ea65d8b8d96e4a7fd0f0ee42e3922536978fe9f4..98a2b6010e3485096509de0d6ac47c37739e723b 100644 (file)
--- a/src/drivers/infiniband/arbel.c
+++ b/src/drivers/infiniband/arbel.c
@@ -1972,6 +1972,7 @@ static int arbel_map_vpm ( struct arbel *arbel,
        assert ( ( va & ( ARBEL_PAGE_SIZE - 1 ) ) == 0 );
        assert ( ( pa & ( ARBEL_PAGE_SIZE - 1 ) ) == 0 );
        assert ( ( len & ( ARBEL_PAGE_SIZE - 1 ) ) == 0 );
+       assert ( len != 0 );
 
        /* Calculate starting points */
        start = pa;