[PATCH AUTOSEL 5.6 69/79] mac80211: sta_info: Add lockdep condition for RCU list usage

Sasha Levin
2020-04-30T14:09:05Z

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