From 2af4b52988fd4f7ae525fcada29d4db8680033d6 Mon Sep 17 00:00:00 2001
From: Thomas Graf <tgraf@suug.ch>
Date: Thu, 5 Feb 2015 02:03:33 +0100
Subject: [PATCH] rhashtable: Wait for RCU readers after final unzip work

We need to wait for all RCU readers to complete after the last bit of
unzipping has been completed. Otherwise the old table is freed up
prematurely.

Fixes: 7e1e77636e36 ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 lib/rhashtable.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index cea4244e032b..fd1033d518c6 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -392,6 +392,8 @@ int rhashtable_expand(struct rhashtable *ht)
 		}
 	}
 
+	synchronize_rcu();
+
 	bucket_table_free(old_tbl);
 	return 0;
 }