From: Helmut Schaa Date: Mon, 30 Jan 2012 14:18:00 +0000 (+0100) Subject: mac80211: Fix incorrect num_sta_ps decrement in ap_sta_ps_end X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=608383bfc04aa222c3e9e896c32f56a5e5deaff0;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git mac80211: Fix incorrect num_sta_ps decrement in ap_sta_ps_end If the driver blocked this specific STA with the help of ieee80211_sta_block_awake we won't clear WLAN_STA_PS_STA later but still decrement num_sta_ps. Hence, the next data frame from this STA will trigger ap_sta_ps_end again and also decrement num_sta_ps again leading to an incorrect num_sta_ps counter. This can result in problems with powersaving clients not waking up from PS because the TIM calculation might be skipped due to the incorrect num_sta_ps counter. Signed-off-by: Helmut Schaa Signed-off-by: John W. Linville --- diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 73d213810a37..ab29253fb4f2 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1145,19 +1145,15 @@ static void ap_sta_ps_start(struct sta_info *sta) static void ap_sta_ps_end(struct sta_info *sta) { - struct ieee80211_sub_if_data *sdata = sta->sdata; - - atomic_dec(&sdata->bss->num_sta_ps); - #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", - sdata->name, sta->sta.addr, sta->sta.aid); + sta->sdata->name, sta->sta.addr, sta->sta.aid); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) { #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", - sdata->name, sta->sta.addr, sta->sta.aid); + sta->sdata->name, sta->sta.addr, sta->sta.aid); #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ return; } diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 0c79593b1bbf..1fb4770a7d13 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -997,9 +997,11 @@ EXPORT_SYMBOL(ieee80211_find_sta); static void clear_sta_ps_flags(void *_sta) { struct sta_info *sta = _sta; + struct ieee80211_sub_if_data *sdata = sta->sdata; clear_sta_flag(sta, WLAN_STA_PS_DRIVER); - clear_sta_flag(sta, WLAN_STA_PS_STA); + if (test_and_clear_sta_flag(sta, WLAN_STA_PS_STA)) + atomic_dec(&sdata->bss->num_sta_ps); } /* powersave support code */