linux-stable/net/mac80211/pm.c
Loic Poulain b33fb28c86 mac80211: Prevent AP probing during suspend
Submitting AP probe/null during suspend can cause unexpected
disconnect on resume because of timeout waiting for ack status:

wlan0: Failed to send nullfunc to AP 11:22:33:44:55:66 after 500ms, disconnecting

This is especially the case when we enter suspend when a scan is
ongoing, indeed, scan is cancelled from __ieee80211_suspend, leading
to a corresponding (aborted) scan complete event, which in turn causes
the submission of an immediate monitor null frame (restart_sta_timer).
The corresponding packet or ack will not be processed before resuming,
causing a timeout & disconnect on resume.

Delay the AP probing when suspending/suspended.

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/1634805927-1113-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-10-21 17:27:51 +02:00

201 lines
5.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Portions
* Copyright (C) 2020-2021 Intel Corporation
*/
#include <net/mac80211.h>
#include <net/rtnetlink.h>
#include "ieee80211_i.h"
#include "mesh.h"
#include "driver-ops.h"
#include "led.h"
static void ieee80211_sched_scan_cancel(struct ieee80211_local *local)
{
if (ieee80211_request_sched_scan_stop(local))
return;
cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0);
}
int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
if (!local->open_count)
goto suspend;
local->suspending = true;
mb(); /* make suspending visible before any cancellation */
ieee80211_scan_cancel(local);
ieee80211_dfs_cac_cancel(local);
ieee80211_roc_purge(local, NULL);
ieee80211_del_virtual_monitor(local);
if (ieee80211_hw_check(hw, AMPDU_AGGREGATION) &&
!(wowlan && wowlan->any)) {
mutex_lock(&local->sta_mtx);
list_for_each_entry(sta, &local->sta_list, list) {
set_sta_flag(sta, WLAN_STA_BLOCK_BA);
ieee80211_sta_tear_down_BA_sessions(
sta, AGG_STOP_LOCAL_REQUEST);
}
mutex_unlock(&local->sta_mtx);
}
/* keep sched_scan only in case of 'any' trigger */
if (!(wowlan && wowlan->any))
ieee80211_sched_scan_cancel(local);
ieee80211_stop_queues_by_reason(hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_SUSPEND,
false);
/* flush out all packets */
synchronize_net();
ieee80211_flush_queues(local, NULL, true);
local->quiescing = true;
/* make quiescing visible to timers everywhere */
mb();
flush_workqueue(local->workqueue);
/* Don't try to run timers while suspended. */
del_timer_sync(&local->sta_cleanup);
/*
* Note that this particular timer doesn't need to be
* restarted at resume.
*/
cancel_work_sync(&local->dynamic_ps_enable_work);
del_timer_sync(&local->dynamic_ps_timer);
local->wowlan = wowlan;
if (local->wowlan) {
int err;
/* Drivers don't expect to suspend while some operations like
* authenticating or associating are in progress. It doesn't
* make sense anyway to accept that, since the authentication
* or association would never finish since the driver can't do
* that on its own.
* Thus, clean up in-progress auth/assoc first.
*/
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (sdata->vif.type != NL80211_IFTYPE_STATION)
continue;
ieee80211_mgd_quiesce(sdata);
/* If suspended during TX in progress, and wowlan
* is enabled (connection will be active) there
* can be a race where the driver is put out
* of power-save due to TX and during suspend
* dynamic_ps_timer is cancelled and TX packet
* is flushed, leaving the driver in ACTIVE even
* after resuming until dynamic_ps_timer puts
* driver back in DOZE.
*/
if (sdata->u.mgd.associated &&
sdata->u.mgd.powersave &&
!(local->hw.conf.flags & IEEE80211_CONF_PS)) {
local->hw.conf.flags |= IEEE80211_CONF_PS;
ieee80211_hw_config(local,
IEEE80211_CONF_CHANGE_PS);
}
}
err = drv_suspend(local, wowlan);
if (err < 0) {
local->quiescing = false;
local->wowlan = false;
if (ieee80211_hw_check(hw, AMPDU_AGGREGATION)) {
mutex_lock(&local->sta_mtx);
list_for_each_entry(sta,
&local->sta_list, list) {
clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
}
mutex_unlock(&local->sta_mtx);
}
ieee80211_wake_queues_by_reason(hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_SUSPEND,
false);
return err;
} else if (err > 0) {
WARN_ON(err != 1);
/* cfg80211 will call back into mac80211 to disconnect
* all interfaces, allow that to proceed properly
*/
ieee80211_wake_queues_by_reason(hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_SUSPEND,
false);
return err;
} else {
goto suspend;
}
}
/* remove all interfaces that were created in the driver */
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
case NL80211_IFTYPE_MONITOR:
continue;
case NL80211_IFTYPE_STATION:
ieee80211_mgd_quiesce(sdata);
break;
default:
break;
}
flush_delayed_work(&sdata->dec_tailroom_needed_wk);
drv_remove_interface(local, sdata);
}
/*
* We disconnected on all interfaces before suspend, all channel
* contexts should be released.
*/
WARN_ON(!list_empty(&local->chanctx_list));
/* stop hardware - this must stop RX */
ieee80211_stop_device(local);
suspend:
local->suspended = true;
/* need suspended to be visible before quiescing is false */
barrier();
local->quiescing = false;
local->suspending = false;
return 0;
}
/*
* __ieee80211_resume() is a static inline which just calls
* ieee80211_reconfig(), which is also needed for hardware
* hang/firmware failure/etc. recovery.
*/
void ieee80211_report_wowlan_wakeup(struct ieee80211_vif *vif,
struct cfg80211_wowlan_wakeup *wakeup,
gfp_t gfp)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
cfg80211_report_wowlan_wakeup(&sdata->wdev, wakeup, gfp);
}
EXPORT_SYMBOL(ieee80211_report_wowlan_wakeup);