Subject: [PATCH] dsa: do not dereference non-existing routing table

From: Tobias Waldekranz <[email-masked]>
Date: Thu, 5 Feb 2015 14:52:06 +0100

In the case where there is only one switch, no routing table will have
been allocated, so do not dereference it in this case.

Signed-off-by: Tobias Waldekranz <[email-masked]>
---
 drivers/net/dsa/mv88e6131.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mv88e6131.c b/drivers/net/dsa/mv88e6131.c
index 1fc98e7..eadb27c 100644
--- a/drivers/net/dsa/mv88e6131.c
+++ b/drivers/net/dsa/mv88e6131.c
@@ -142,7 +142,8 @@ static int mv88e6131_setup_global(struct dsa_switch *ds)
 		int nexthop;
 
 		nexthop = 0x1f;
-		if (i != ds->index && i < ds->dst->pd->nr_chips)
+		if (ds->pd->rtable &&
+		    i != ds->index && i < ds->dst->pd->nr_chips)
 			nexthop = ds->pd->rtable[i] & 0x1f;
 
 		REG_WRITE(REG_GLOBAL2, 0x06, 0x8000 | (i << 8) | nexthop);
-- 
1.8.4.357.g8d83871.dirty