Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.4 27/50] mac80211: sta_info: Add lockdep condition for RCU list usage
Date:   Fri,  8 May 2020 14:35:33 +0200
Message-Id: <20200508123047.119009426@linuxfoundation.org>
In-Reply-To: <20200508123043.085296641@linuxfoundation.org>
References: <20200508123043.085296641@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>

[ Upstream commit 8ca47eb9f9e4e10e7e7fa695731a88941732c38d ]

The function sta_info_get_by_idx() uses RCU list primitive.
It is called with  local->sta_mtx held from mac80211/cfg.c.
Add lockdep expression to avoid any false positive RCU list warnings.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200409082906.27427-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/mac80211/sta_info.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 21b1422b1b1c3..b1669f0244706 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -217,7 +217,8 @@ struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
 	struct sta_info *sta;
 	int i = 0;
 
-	list_for_each_entry_rcu(sta, &local->sta_list, list) {
+	list_for_each_entry_rcu(sta, &local->sta_list, list,
+				lockdep_is_held(&local->sta_mtx)) {
 		if (sdata != sta->sdata)
 			continue;
 		if (i < idx) {
-- 
2.20.1