bridge: master device stuck in no-carrier state forever when in user-stp mode

When in user-stp mode, bridge master do not follow state of its slaves, so
after the following sequence of events it can stuck forever in no-carrier
state:
1) turn stp off
2) put all slaves down - master device will follow their state and also go in
no-carrier state
3) turn stp on with bridge-stp script returning 0 (go to the user-stp mode)
Now bridge master won't follow slaves' state and will never reach running
state.

This patch solves the problem by making user-stp and kernel-stp behavior
similar regarding master following slaves' states.

Signed-off-by: Vitalii Demianets <vitas@nppfactor.kiev.ua>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index e5f9ece3c9a0..a1daf8227ed1 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -18,6 +18,7 @@
 #include <net/sock.h>
 
 #include "br_private.h"
+#include "br_private_stp.h"
 
 static inline size_t br_nlmsg_size(void)
 {
@@ -188,6 +189,11 @@ static int br_rtm_setlink(struct sk_buff *skb,  struct nlmsghdr *nlh, void *arg)
 
         p->state = new_state;
         br_log_state(p);
+
+        spin_lock_bh(&p->br->lock);
+        br_port_state_selection(p->br);
+        spin_unlock_bh(&p->br->lock);
+
         br_ifinfo_notify(RTM_NEWLINK, p);
 
         return 0;