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: [<ffffffffa0492d13>] 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);
<Interrupt>
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 <kvalo@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath6kl/cfg80211.c b/drivers/net/wireless/ath/ath6kl/cfg80211.c
index 5dab4f2..4a880b4 100644
--- a/drivers/net/wireless/ath/ath6kl/cfg80211.c
+++ b/drivers/net/wireless/ath/ath6kl/cfg80211.c
@@ -1320,9 +1320,9 @@
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 @@
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 83b4f16..bb2254d 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -1685,17 +1685,17 @@
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 23da82e..f9410e4 100644
--- a/drivers/net/wireless/ath/ath6kl/main.c
+++ b/drivers/net/wireless/ath/ath6kl/main.c
@@ -1046,15 +1046,15 @@
{
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 9dfd7f5..06e4912 100644
--- a/drivers/net/wireless/ath/ath6kl/txrx.c
+++ b/drivers/net/wireless/ath/ath6kl/txrx.c
@@ -470,10 +470,10 @@
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 @@
return action;
}
}
- spin_unlock(&ar->list_lock);
+ spin_unlock_bh(&ar->list_lock);
return action;
}
@@ -637,16 +637,16 @@
__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 d3db5b3..ece67a5 100644
--- a/drivers/net/wireless/ath/ath6kl/wmi.c
+++ b/drivers/net/wireless/ath/ath6kl/wmi.c
@@ -89,14 +89,14 @@
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;
}