IB/cm: avoid reusing local ID

Use an increasing local ID to avoid re-using identifiers while
messages may still be outstanding on the old ID.  Without this, a
quick connect-disconnect-connect sequence can fail by matching
messages for the new connection with the old connection.

Signed-off-by: Sean Hefty <[email protected]>
Signed-off-by: Roland Dreier <[email protected]>

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index 1fe21865d1f2580d82cdb0bebf2a83ad680b0cd2..3a611fe5497e06c0b9e2de2cc9eaf75d2abf0caa 100644 (file)
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -308,10 +308,11 @@ static int cm_alloc_id(struct cm_id_private *cm_id_priv)
 {
        unsigned long flags;
        int ret;
+       static int next_id;
 
        do {
                spin_lock_irqsave(&cm.lock, flags);
-               ret = idr_get_new_above(&cm.local_id_table, cm_id_priv, 1,
+               ret = idr_get_new_above(&cm.local_id_table, cm_id_priv, next_id++,
                                        (__force int *) &cm_id_priv->id.local_id);
                spin_unlock_irqrestore(&cm.lock, flags);
        } while( (ret == -EAGAIN) && idr_pre_get(&cm.local_id_table, GFP_KERNEL) );