From 11f6e40d9f21767a9090e4e559d3c63edf25e6c0 Mon Sep 17 00:00:00 2001 From: Vasanthakumar Thiagarajan Date: Tue, 1 Nov 2011 16:38:50 +0530 Subject: [PATCH] ath6kl: Fix lockdep warning The following is the lockdep warning which detects possible deadlock condition with the way ar->lock and ar->list_lock are being used. (&(&ar->lock)->rlock){+.-...}, at: [] ath6kl_indicate_tx_activity+0x83/0x110 [ath6kl] but this lock took another, SOFTIRQ-unsafe lock in the past: (&(&ar->list_lock)->rlock){+.+...} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&ar->list_lock)->rlock); local_irq_disable(); lock(&(&ar->lock)->rlock); lock(&(&ar->list_lock)->rlock); lock(&(&ar->lock)->rlock); *** DEADLOCK *** softirqs have to be disabled when acquiring ar->list_lock to avoid the above deadlock condition. When the above warning printed the interface is still up and running without issue. Reported-by: Kalle Valo Signed-off-by: Vasanthakumar Thiagarajan Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/ath6kl/cfg80211.c | 8 ++++---- drivers/net/wireless/ath/ath6kl/init.c | 8 ++++---- drivers/net/wireless/ath/ath6kl/main.c | 6 +++--- drivers/net/wireless/ath/ath6kl/txrx.c | 14 +++++++------- drivers/net/wireless/ath/ath6kl/wmi.c | 4 ++-- 5 files changed, 20 insertions(+), 20 deletions(-) diff --git a/drivers/net/wireless/ath/ath6kl/cfg80211.c b/drivers/net/wireless/ath/ath6kl/cfg80211.c index 5dab4f20146a..4a880b4dda5b 100644 --- a/drivers/net/wireless/ath/ath6kl/cfg80211.c +++ b/drivers/net/wireless/ath/ath6kl/cfg80211.c @@ -1320,9 +1320,9 @@ static int ath6kl_cfg80211_del_iface(struct wiphy *wiphy, struct ath6kl *ar = wiphy_priv(wiphy); struct ath6kl_vif *vif = netdev_priv(ndev); - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_del(&vif->list); - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); ath6kl_cleanup_vif(vif, test_bit(WMI_READY, &ar->flag)); @@ -2437,9 +2437,9 @@ struct net_device *ath6kl_interface_add(struct ath6kl *ar, char *name, if (type == NL80211_IFTYPE_ADHOC) ar->ibss_if_active = true; - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_add_tail(&vif->list, &ar->vif_list); - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); return ndev; diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c index 83b4f165eebf..bb2254d3b439 100644 --- a/drivers/net/wireless/ath/ath6kl/init.c +++ b/drivers/net/wireless/ath/ath6kl/init.c @@ -1685,17 +1685,17 @@ void ath6kl_stop_txrx(struct ath6kl *ar) return; } - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_for_each_entry_safe(vif, tmp_vif, &ar->vif_list, list) { list_del(&vif->list); - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); ath6kl_cleanup_vif(vif, test_bit(WMI_READY, &ar->flag)); rtnl_lock(); ath6kl_deinit_if_data(vif); rtnl_unlock(); - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); } - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); clear_bit(WMI_READY, &ar->flag); diff --git a/drivers/net/wireless/ath/ath6kl/main.c b/drivers/net/wireless/ath/ath6kl/main.c index 23da82e148ea..f9410e41121a 100644 --- a/drivers/net/wireless/ath/ath6kl/main.c +++ b/drivers/net/wireless/ath/ath6kl/main.c @@ -1046,15 +1046,15 @@ struct ath6kl_vif *ath6kl_vif_first(struct ath6kl *ar) { struct ath6kl_vif *vif; - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); if (list_empty(&ar->vif_list)) { - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); return NULL; } vif = list_first_entry(&ar->vif_list, struct ath6kl_vif, list); - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); return vif; } diff --git a/drivers/net/wireless/ath/ath6kl/txrx.c b/drivers/net/wireless/ath/ath6kl/txrx.c index 9dfd7f56d043..06e4912f0321 100644 --- a/drivers/net/wireless/ath/ath6kl/txrx.c +++ b/drivers/net/wireless/ath/ath6kl/txrx.c @@ -470,10 +470,10 @@ enum htc_send_full_action ath6kl_tx_queue_full(struct htc_target *target, stop_adhoc_netq: /* FIXME: Locking */ - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_for_each_entry(vif, &ar->vif_list, list) { if (vif->nw_type == ADHOC_NETWORK) { - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); spin_lock_bh(&vif->if_lock); set_bit(NETQ_STOPPED, &vif->flags); @@ -483,7 +483,7 @@ stop_adhoc_netq: return action; } } - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); return action; } @@ -637,16 +637,16 @@ void ath6kl_tx_complete(void *context, struct list_head *packet_queue) __skb_queue_purge(&skb_queue); /* FIXME: Locking */ - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_for_each_entry(vif, &ar->vif_list, list) { if (test_bit(CONNECTED, &vif->flags) && !flushing[vif->fw_vif_idx]) { - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); netif_wake_queue(vif->ndev); - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); } } - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); if (wake_event) wake_up(&ar->event_wq); diff --git a/drivers/net/wireless/ath/ath6kl/wmi.c b/drivers/net/wireless/ath/ath6kl/wmi.c index d3db5b3c40bc..ece67a5c37b3 100644 --- a/drivers/net/wireless/ath/ath6kl/wmi.c +++ b/drivers/net/wireless/ath/ath6kl/wmi.c @@ -89,14 +89,14 @@ struct ath6kl_vif *ath6kl_get_vif_by_index(struct ath6kl *ar, u8 if_idx) return NULL; /* FIXME: Locking */ - spin_lock(&ar->list_lock); + spin_lock_bh(&ar->list_lock); list_for_each_entry(vif, &ar->vif_list, list) { if (vif->fw_vif_idx == if_idx) { found = vif; break; } } - spin_unlock(&ar->list_lock); + spin_unlock_bh(&ar->list_lock); return found; } -- 2.20.1