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From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Sasha Levin <sashal@kernel.org>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 5.6 69/79] mac80211: sta_info: Add lockdep condition for RCU list usage
Date:   Thu, 30 Apr 2020 09:50:33 -0400
Message-Id: <20200430135043.19851-69-sashal@kernel.org>
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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 e3572be307d6c..149ed0510778d 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -231,7 +231,8 @@ 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