RDS: always free recv frag as we free its ring entry

[linux-block.git] / net / rds / ib_recv.c

diff --git a/net/rds/ib_recv.c b/net/rds/ib_recv.c
index cac5b4506ee387053d0baf64b1c588cbab8e0f5e..2a6a75c599435fd4a859ec8f8d13535c60195376 100644 (file)
--- a/net/rds/ib_recv.c
+++ b/net/rds/ib_recv.c
@@ -982,10 +982,17 @@ static inline void rds_poll_cq(struct rds_ib_connection *ic,
                }
 
                /*
-                * It's very important that we only free this ring entry if we've truly
-                * freed the resources allocated to the entry.  The refilling path can
-                * leak if we don't.
+                * rds_ib_process_recv() doesn't always consume the frag, and
+                * we might not have called it at all if the wc didn't indicate
+                * success. We already unmapped the frag's pages, though, and
+                * the following rds_ib_ring_free() call tells the refill path
+                * that it will not find an allocated frag here. Make sure we
+                * keep that promise by freeing a frag that's still on the ring.
                 */
+               if (recv->r_frag) {
+                       rds_ib_frag_free(ic, recv->r_frag);
+                       recv->r_frag = NULL;
+               }
                rds_ib_ring_free(&ic->i_recv_ring, 1);
        }
 }