wifi: mac80211: don't enter idle during link switch

When doing link switch with a disjoint set of links before
and after the switch, we end up removing all channel contexts,
adding new ones later. This looks like 'idle' to the code now,
and we enter idle which also includes flushing queues. But we
can't actually flush since we don't have a link active (bound
to a channel context), and entering idle just to leave it again
is also wrong.

Fix this by passing through an indication that we shouldn't do
any idle checks in this case.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240320091155.170328bac555.If4a522a9dd3133b91983854b909a4de13aa635da@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 19 insertions, 15 deletions

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 80e4b9784131..5a7fb0e4f89d 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -695,26 +695,29 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
 }
 
 static void ieee80211_del_chanctx(struct ieee80211_local *local,
-				  struct ieee80211_chanctx *ctx)
+				  struct ieee80211_chanctx *ctx,
+				  bool skip_idle_recalc)
 {
 	lockdep_assert_wiphy(local->hw.wiphy);
 
 	drv_remove_chanctx(local, ctx);
 
-	ieee80211_recalc_idle(local);
+	if (!skip_idle_recalc)
+		ieee80211_recalc_idle(local);
 
 	ieee80211_remove_wbrf(local, &ctx->conf.def);
 }
 
 static void ieee80211_free_chanctx(struct ieee80211_local *local,
-				   struct ieee80211_chanctx *ctx)
+				   struct ieee80211_chanctx *ctx,
+				   bool skip_idle_recalc)
 {
 	lockdep_assert_wiphy(local->hw.wiphy);
 
 	WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 
 	list_del_rcu(&ctx->list);
-	ieee80211_del_chanctx(local, ctx);
+	ieee80211_del_chanctx(local, ctx, skip_idle_recalc);
 	kfree_rcu(ctx, rcu_head);
 }
 
@@ -1002,7 +1005,7 @@ int ieee80211_link_unreserve_chanctx(struct ieee80211_link_data *link)
 			list_del_rcu(&ctx->list);
 			kfree_rcu(ctx, rcu_head);
 		} else {
-			ieee80211_free_chanctx(sdata->local, ctx);
+			ieee80211_free_chanctx(sdata->local, ctx, false);
 		}
 	}
 
@@ -1218,7 +1221,7 @@ ieee80211_link_use_reserved_reassign(struct ieee80211_link_data *link)
 				     CHANCTX_SWMODE_REASSIGN_VIF);
 	if (err) {
 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
-			ieee80211_free_chanctx(local, new_ctx);
+			ieee80211_free_chanctx(local, new_ctx, false);
 
 		goto out;
 	}
@@ -1232,7 +1235,7 @@ ieee80211_link_use_reserved_reassign(struct ieee80211_link_data *link)
 	ieee80211_check_fast_xmit_iface(sdata);
 
 	if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
-		ieee80211_free_chanctx(local, old_ctx);
+		ieee80211_free_chanctx(local, old_ctx, false);
 
 	ieee80211_recalc_chanctx_min_def(local, new_ctx, NULL);
 	ieee80211_recalc_smps_chanctx(local, new_ctx);
@@ -1286,7 +1289,7 @@ ieee80211_link_use_reserved_assign(struct ieee80211_link_data *link)
 	err = ieee80211_assign_link_chanctx(link, new_ctx);
 	if (err) {
 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
-			ieee80211_free_chanctx(local, new_ctx);
+			ieee80211_free_chanctx(local, new_ctx, false);
 
 		goto out;
 	}
@@ -1383,7 +1386,7 @@ static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
 		if (!list_empty(&ctx->replace_ctx->assigned_links))
 			continue;
 
-		ieee80211_del_chanctx(local, ctx->replace_ctx);
+		ieee80211_del_chanctx(local, ctx->replace_ctx, false);
 		err = ieee80211_add_chanctx(local, ctx);
 		if (err)
 			goto err;
@@ -1400,7 +1403,7 @@ err:
 		if (!list_empty(&ctx->replace_ctx->assigned_links))
 			continue;
 
-		ieee80211_del_chanctx(local, ctx);
+		ieee80211_del_chanctx(local, ctx, false);
 		WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
 	}
 
@@ -1652,7 +1655,8 @@ err:
 	return err;
 }
 
-static void __ieee80211_link_release_channel(struct ieee80211_link_data *link)
+void __ieee80211_link_release_channel(struct ieee80211_link_data *link,
+				      bool skip_idle_recalc)
 {
 	struct ieee80211_sub_if_data *sdata = link->sdata;
 	struct ieee80211_bss_conf *link_conf = link->conf;
@@ -1680,7 +1684,7 @@ static void __ieee80211_link_release_channel(struct ieee80211_link_data *link)
 
 	ieee80211_assign_link_chanctx(link, NULL);
 	if (ieee80211_chanctx_refcount(local, ctx) == 0)
-		ieee80211_free_chanctx(local, ctx);
+		ieee80211_free_chanctx(local, ctx, skip_idle_recalc);
 
 	link->radar_required = false;
 
@@ -1721,7 +1725,7 @@ int ieee80211_link_use_channel(struct ieee80211_link_data *link,
 	if (ret < 0)
 		goto out;
 
-	__ieee80211_link_release_channel(link);
+	__ieee80211_link_release_channel(link, false);
 
 	ctx = ieee80211_find_chanctx(local, chanreq, mode);
 	if (!ctx)
@@ -1737,7 +1741,7 @@ int ieee80211_link_use_channel(struct ieee80211_link_data *link,
 	if (ret) {
 		/* if assign fails refcount stays the same */
 		if (ieee80211_chanctx_refcount(local, ctx) == 0)
-			ieee80211_free_chanctx(local, ctx);
+			ieee80211_free_chanctx(local, ctx, false);
 		goto out;
 	}
 
@@ -1930,7 +1934,7 @@ void ieee80211_link_release_channel(struct ieee80211_link_data *link)
 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
 
 	if (rcu_access_pointer(link->conf->chanctx_conf))
-		__ieee80211_link_release_channel(link);
+		__ieee80211_link_release_channel(link, false);
 }
 
 void ieee80211_link_vlan_copy_chanctx(struct ieee80211_link_data *link)