lkml.org 
[lkml]   [2020]   [Apr]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/4] net: mac80211: util.c: Fix RCU list usage warnings
Date
From: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>

This patch fixes the following warning (CONIG_PROVE_RCU_LIST)
in ieee80211_check_combinations().

WARNING: suspicious RCU usage
[ 80.933723] 5.6.0+ #4 Not tainted
[ 80.933733] -----------------------------
[ 80.933746] net/mac80211/util.c:3934 RCU-list traversed in non-reader section!!

Also, fix the other uses of list_for_each_entry_rcu() by either using
list_for_each_entry() instead (When mutex or spinlock is always held
in the function) or pass the necessary lockdep condition.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
---
net/mac80211/util.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 20436c86b9bf..f4b0434024c0 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -254,7 +254,7 @@ static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac)

sdata->vif.txqs_stopped[ac] = false;

- list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ list_for_each_entry(sta, &local->sta_list, list) {
if (sdata != sta->sdata)
continue;

@@ -719,7 +719,8 @@ static void __iterate_interfaces(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata;
bool active_only = iter_flags & IEEE80211_IFACE_ITER_ACTIVE;

- list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+ list_for_each_entry_rcu(sdata, &local->interfaces, list,
+ (lockdep_is_held(&local->iflist_mtx)|| lockdep_rtnl_is_held())) {
switch (sdata->vif.type) {
case NL80211_IFTYPE_MONITOR:
if (!(sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE))
@@ -3931,7 +3932,7 @@ int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
params.num_different_channels++;
}

- list_for_each_entry_rcu(sdata_iter, &local->interfaces, list) {
+ list_for_each_entry(sdata_iter, &local->interfaces, list) {
struct wireless_dev *wdev_iter;

wdev_iter = &sdata_iter->wdev;
@@ -3982,7 +3983,7 @@ int ieee80211_max_num_channels(struct ieee80211_local *local)
ieee80211_chanctx_radar_detect(local, ctx);
}

- list_for_each_entry_rcu(sdata, &local->interfaces, list)
+ list_for_each_entry(sdata, &local->interfaces, list)
params.iftype_num[sdata->wdev.iftype]++;

err = cfg80211_iter_combinations(local->hw.wiphy, &params,
--
2.17.1
\
 
 \ /
  Last update: 2020-04-09 10:29    [W:0.061 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site