1 files changed, 14 insertions, 3 deletions

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 166165efd8e2..03e8d2e3270e 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -79,6 +79,7 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
                       enum ieee80211_chanctx_mode mode)
 {
         struct ieee80211_chanctx *ctx;
+        u32 changed;
         int err;
 
         lockdep_assert_held(&local->chanctx_mtx);
@@ -95,6 +96,13 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
         if (!local->use_chanctx)
                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 
+        /* acquire mutex to prevent idle from changing */
+        mutex_lock(&local->mtx);
+        /* turn idle off *before* setting channel -- some drivers need that */
+        changed = ieee80211_idle_off(local);
+        if (changed)
+                ieee80211_hw_config(local, changed);
+
         if (!local->use_chanctx) {
                 local->_oper_chandef = *chandef;
                 ieee80211_hw_config(local, 0);
@@ -102,14 +110,17 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
                 err = drv_add_chanctx(local, ctx);
                 if (err) {
                         kfree(ctx);
-                        return ERR_PTR(err);
+                        ctx = ERR_PTR(err);
+
+                        ieee80211_recalc_idle(local);
+                        goto out;
                 }
         }
 
+        /* and keep the mutex held until the new chanctx is on the list */
         list_add_rcu(&ctx->list, &local->chanctx_list);
 
-        mutex_lock(&local->mtx);
-        ieee80211_recalc_idle(local);
+ out:
         mutex_unlock(&local->mtx);
 
         return ctx;