Dave,
Stanislaw has given us two late-breaking fixes intended for 3.3. One
avoids a NULL pointer dereference in iwl3945, and the other corrects a
locking issue in the rt2x00 driver that can lead to random traffic
stalls.
Please let me know if there are problems!
Thanks,
John
---
The following changes since commit 1ab5ecb90cb6a3df1476e052f76a6e8f6511cb3d:
tun: don't hold network namespace by tun sockets (2012-03-12 17:14:00 -0700)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless.git for-davem
John W. Linville (1):
Merge branch 'master' of git://git.kernel.org/.../linville/wireless into for-davem
Stanislaw Gruszka (2):
iwl3945: fix possible il->txq NULL pointer dereference in delayed works
rt2x00: fix random stalls
drivers/net/wireless/iwlegacy/3945-mac.c | 2 +-
drivers/net/wireless/iwlegacy/3945.c | 7 ++++---
drivers/net/wireless/rt2x00/rt2x00dev.c | 6 +++++-
drivers/net/wireless/rt2x00/rt2x00mac.c | 9 +++++++++
drivers/net/wireless/rt2x00/rt2x00queue.c | 3 +++
5 files changed, 22 insertions(+), 5 deletions(-)
diff --git a/drivers/net/wireless/iwlegacy/3945-mac.c b/drivers/net/wireless/iwlegacy/3945-mac.c
index 54b2d39..a7dfba8 100644
--- a/drivers/net/wireless/iwlegacy/3945-mac.c
+++ b/drivers/net/wireless/iwlegacy/3945-mac.c
@@ -2475,7 +2475,7 @@ il3945_bg_alive_start(struct work_struct *data)
container_of(data, struct il_priv, alive_start.work);
mutex_lock(&il->mutex);
- if (test_bit(S_EXIT_PENDING, &il->status))
+ if (test_bit(S_EXIT_PENDING, &il->status) || il->txq == NULL)
goto out;
il3945_alive_start(il);
diff --git a/drivers/net/wireless/iwlegacy/3945.c b/drivers/net/wireless/iwlegacy/3945.c
index 1489b15..c80eb9b 100644
--- a/drivers/net/wireless/iwlegacy/3945.c
+++ b/drivers/net/wireless/iwlegacy/3945.c
@@ -1870,11 +1870,12 @@ il3945_bg_reg_txpower_periodic(struct work_struct *work)
struct il_priv *il = container_of(work, struct il_priv,
_3945.thermal_periodic.work);
- if (test_bit(S_EXIT_PENDING, &il->status))
- return;
-
mutex_lock(&il->mutex);
+ if (test_bit(S_EXIT_PENDING, &il->status) || il->txq == NULL)
+ goto out;
+
il3945_reg_txpower_periodic(il);
+out:
mutex_unlock(&il->mutex);
}
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index d2a1ea9..fd356b7 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -426,10 +426,14 @@ void rt2x00lib_txdone(struct queue_entry *entry,
/*
* If the data queue was below the threshold before the txdone
* handler we must make sure the packet queue in the mac80211 stack
- * is reenabled when the txdone handler has finished.
+ * is reenabled when the txdone handler has finished. This has to be
+ * serialized with rt2x00mac_tx(), otherwise we can wake up queue
+ * before it was stopped.
*/
+ spin_lock_bh(&entry->queue->tx_lock);
if (!rt2x00queue_threshold(entry->queue))
rt2x00queue_unpause_queue(entry->queue);
+ spin_unlock_bh(&entry->queue->tx_lock);
}
EXPORT_SYMBOL_GPL(rt2x00lib_txdone);
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index ede3c58..2df2eb6 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -152,13 +152,22 @@ void rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
if (unlikely(rt2x00queue_write_tx_frame(queue, skb, false)))
goto exit_fail;
+ /*
+ * Pausing queue has to be serialized with rt2x00lib_txdone(). Note
+ * we should not use spin_lock_bh variant as bottom halve was already
+ * disabled before ieee80211_xmit() call.
+ */
+ spin_lock(&queue->tx_lock);
if (rt2x00queue_threshold(queue))
rt2x00queue_pause_queue(queue);
+ spin_unlock(&queue->tx_lock);
return;
exit_fail:
+ spin_lock(&queue->tx_lock);
rt2x00queue_pause_queue(queue);
+ spin_unlock(&queue->tx_lock);
exit_free_skb:
ieee80211_free_txskb(hw, skb);
}
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 5adfb3e..9b1b2b7 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -619,6 +619,9 @@ int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb,
else if (test_bit(REQUIRE_DMA, &queue->rt2x00dev->cap_flags))
rt2x00queue_align_frame(skb);
+ /*
+ * That function must be called with bh disabled.
+ */
spin_lock(&queue->tx_lock);
if (unlikely(rt2x00queue_full(queue))) {
--
John W. Linville Someday the world will need a hero, and you
linville@xxxxxxxxxxxxx might be all we have. Be ready.
Attachment:
pgpL7UrRlrnQn.pgp
Description: PGP signature
