From 58e64a312c8468f3e8adead24b71ebb3039b381e Mon Sep 17 00:00:00 2001
From: Wei Yongjun <weiyongjun1@huawei.com>
Date: Wed, 22 Apr 2020 10:11:35 +0800
Subject: [PATCH] macvlan: silence RCU list debugging warning
macvlan_hash_lookup() uses list_for_each_entry_rcu() for traversing
should either under RCU in fast path or the protection of rtnl_mutex.
In the case of holding RTNL, we should add the corresponding lockdep
expression to silence the following false-positive warning:
=============================
WARNING: suspicious RCU usage
5.7.0-rc1-next-20200416-00003-ga3b8d28bc #1 Not tainted
-----------------------------
drivers/net/macvlan.c:126 RCU-list traversed in non-reader section!!
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/macvlan.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index e7289d67268fc..654c1fa11826c 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -123,7 +123,8 @@ static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
struct macvlan_dev *vlan;
u32 idx = macvlan_eth_hash(addr);
- hlist_for_each_entry_rcu(vlan, &port->vlan_hash[idx], hlist) {
+ hlist_for_each_entry_rcu(vlan, &port->vlan_hash[idx], hlist,
+ lockdep_rtnl_is_held()) {
if (ether_addr_equal_64bits(vlan->dev->dev_addr, addr))
return vlan;
}
--
2.30.2