From a100885d9dfd8685e0b4e442afc9041ee4c90586 Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Sat, 12 Feb 2011 23:24:20 +0200 Subject: [PATCH] wl12xx: avoid blocking while holding rcu lock on bss info change Some blocking functions were called while holding the rcu lock for accessing STA information. This can lead to a deadlock. Save the required info beforehand and release the rcu without blocking. Signed-off-by: Arik Nemtsov Signed-off-by: Luciano Coelho --- drivers/net/wireless/wl12xx/main.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c index cf8b3ce..d51d559 100644 --- a/drivers/net/wireless/wl12xx/main.c +++ b/drivers/net/wireless/wl12xx/main.c @@ -2222,6 +2222,8 @@ static void wl1271_bss_info_changed_sta(struct wl1271 *wl, u32 sta_rate_set = 0; int ret; struct ieee80211_sta *sta; + bool sta_exists = false; + struct ieee80211_sta_ht_cap sta_ht_cap; if (is_ibss) { ret = wl1271_bss_beacon_info_changed(wl, vif, bss_conf, @@ -2293,16 +2295,20 @@ static void wl1271_bss_info_changed_sta(struct wl1271 *wl, if (sta->ht_cap.ht_supported) sta_rate_set |= (sta->ht_cap.mcs.rx_mask[0] << HW_HT_RATES_OFFSET); + sta_ht_cap = sta->ht_cap; + sta_exists = true; + } + rcu_read_unlock(); + if (sta_exists) { /* handle new association with HT and HT information change */ if ((changed & BSS_CHANGED_HT) && (bss_conf->channel_type != NL80211_CHAN_NO_HT)) { - ret = wl1271_acx_set_ht_capabilities(wl, &sta->ht_cap, + ret = wl1271_acx_set_ht_capabilities(wl, &sta_ht_cap, true); if (ret < 0) { wl1271_warning("Set ht cap true failed %d", ret); - rcu_read_unlock(); goto out; } ret = wl1271_acx_set_ht_information(wl, @@ -2310,23 +2316,20 @@ static void wl1271_bss_info_changed_sta(struct wl1271 *wl, if (ret < 0) { wl1271_warning("Set ht information failed %d", ret); - rcu_read_unlock(); goto out; } } /* handle new association without HT and disassociation */ else if (changed & BSS_CHANGED_ASSOC) { - ret = wl1271_acx_set_ht_capabilities(wl, &sta->ht_cap, + ret = wl1271_acx_set_ht_capabilities(wl, &sta_ht_cap, false); if (ret < 0) { wl1271_warning("Set ht cap false failed %d", ret); - rcu_read_unlock(); goto out; } } } - rcu_read_unlock(); if ((changed & BSS_CHANGED_ASSOC)) { if (bss_conf->assoc) { -- 2.7.4