From: NeilBrown <neilb@suse.com>
Date: Mon, 18 Jun 2018 02:52:50 +0000 (+1000)
Subject: rhashtable: silence RCU warning in rhashtable_test.
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=cbab901296232b1247b46e6e127103d2f738d783;p=linux.git

rhashtable: silence RCU warning in rhashtable_test.

print_ht in rhashtable_test calls rht_dereference() with neither
RCU protection or the mutex.  This triggers an RCU warning.
So take the mutex to silence the warning.

Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index fb69681091134..6ca59ffcacbe2 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -501,6 +501,8 @@ static unsigned int __init print_ht(struct rhltable *rhlt)
 	unsigned int i, cnt = 0;
 
 	ht = &rhlt->ht;
+	/* Take the mutex to avoid RCU warning */
+	mutex_lock(&ht->mutex);
 	tbl = rht_dereference(ht->tbl, ht);
 	for (i = 0; i < tbl->size; i++) {
 		struct rhash_head *pos, *next;
@@ -534,6 +536,7 @@ static unsigned int __init print_ht(struct rhltable *rhlt)
 		}
 	}
 	printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
+	mutex_unlock(&ht->mutex);
 
 	return cnt;
 }