When stress testing AP-mode I hit OOPS when unpluging or rmmodding
driver.
It appears that when tx-queue is disabled, tx-urbs might be left pending.
These can cause ehci to call non-existing tx_urb_complete() (after rmmod)
or uninitialized/reseted private structure (after disconnect()). Add skb
queue for submitted packets and unlink pending urbs on zd_usb_disable_tx().
Part of the problem seems to be usb->free_urb_list that isn't always
working as it should, causing machine freeze when trying to free the list
in zd_usb_disable_tx(). Caching free urbs isn't what other drivers seem
to be doing (usbnet for example) so strip free_usb_list.
Patch makes tx-urb handling saner with use of urb anchors.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@xxxxxxxx>
---
drivers/net/wireless/zd1211rw/zd_usb.c | 108 +++++++++++---------------------
drivers/net/wireless/zd1211rw/zd_usb.h | 8 +-
2 files changed, 41 insertions(+), 75 deletions(-)
diff --git a/drivers/net/wireless/zd1211rw/zd_usb.c b/drivers/net/wireless/zd1211rw/zd_usb.c
index 06041cb..c32a247 100644
--- a/drivers/net/wireless/zd1211rw/zd_usb.c
+++ b/drivers/net/wireless/zd1211rw/zd_usb.c
@@ -779,19 +779,20 @@ void zd_usb_disable_tx(struct zd_usb *usb)
{
struct zd_usb_tx *tx = &usb->tx;
unsigned long flags;
- struct list_head *pos, *n;
+
+ atomic_set(&tx->enabled, 0);
+
+ /* kill all submitted tx-urbs */
+ usb_kill_anchored_urbs(&tx->submitted);
spin_lock_irqsave(&tx->lock, flags);
- list_for_each_safe(pos, n, &tx->free_urb_list) {
- list_del(pos);
- usb_free_urb(list_entry(pos, struct urb, urb_list));
- }
- tx->enabled = 0;
+ WARN_ON(tx->submitted_urbs != 0);
tx->submitted_urbs = 0;
+ spin_unlock_irqrestore(&tx->lock, flags);
+
/* The stopped state is ignored, relying on ieee80211_wake_queues()
* in a potentionally following zd_usb_enable_tx().
*/
- spin_unlock_irqrestore(&tx->lock, flags);
}
/**
@@ -807,63 +808,13 @@ void zd_usb_enable_tx(struct zd_usb *usb)
struct zd_usb_tx *tx = &usb->tx;
spin_lock_irqsave(&tx->lock, flags);
- tx->enabled = 1;
+ atomic_set(&tx->enabled, 1);
tx->submitted_urbs = 0;
ieee80211_wake_queues(zd_usb_to_hw(usb));
tx->stopped = 0;
spin_unlock_irqrestore(&tx->lock, flags);
}
-/**
- * alloc_tx_urb - provides an tx URB
- * @usb: a &struct zd_usb pointer
- *
- * Allocates a new URB. If possible takes the urb from the free list in
- * usb->tx.
- */
-static struct urb *alloc_tx_urb(struct zd_usb *usb)
-{
- struct zd_usb_tx *tx = &usb->tx;
- unsigned long flags;
- struct list_head *entry;
- struct urb *urb;
-
- spin_lock_irqsave(&tx->lock, flags);
- if (list_empty(&tx->free_urb_list)) {
- urb = usb_alloc_urb(0, GFP_ATOMIC);
- goto out;
- }
- entry = tx->free_urb_list.next;
- list_del(entry);
- urb = list_entry(entry, struct urb, urb_list);
-out:
- spin_unlock_irqrestore(&tx->lock, flags);
- return urb;
-}
-
-/**
- * free_tx_urb - frees a used tx URB
- * @usb: a &struct zd_usb pointer
- * @urb: URB to be freed
- *
- * Frees the transmission URB, which means to put it on the free URB
- * list.
- */
-static void free_tx_urb(struct zd_usb *usb, struct urb *urb)
-{
- struct zd_usb_tx *tx = &usb->tx;
- unsigned long flags;
-
- spin_lock_irqsave(&tx->lock, flags);
- if (!tx->enabled) {
- usb_free_urb(urb);
- goto out;
- }
- list_add(&urb->urb_list, &tx->free_urb_list);
-out:
- spin_unlock_irqrestore(&tx->lock, flags);
-}
-
static void tx_dec_submitted_urbs(struct zd_usb *usb)
{
struct zd_usb_tx *tx = &usb->tx;
@@ -905,6 +856,16 @@ static void tx_urb_complete(struct urb *urb)
struct sk_buff *skb;
struct ieee80211_tx_info *info;
struct zd_usb *usb;
+ struct zd_usb_tx *tx;
+
+ skb = (struct sk_buff *)urb->context;
+ info = IEEE80211_SKB_CB(skb);
+ /*
+ * grab 'usb' pointer before handing off the skb (since
+ * it might be freed by zd_mac_tx_to_dev or mac80211)
+ */
+ usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
+ tx = &usb->tx;
switch (urb->status) {
case 0:
@@ -922,20 +883,15 @@ static void tx_urb_complete(struct urb *urb)
goto resubmit;
}
free_urb:
- skb = (struct sk_buff *)urb->context;
- /*
- * grab 'usb' pointer before handing off the skb (since
- * it might be freed by zd_mac_tx_to_dev or mac80211)
- */
- info = IEEE80211_SKB_CB(skb);
- usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
zd_mac_tx_to_dev(skb, urb->status);
- free_tx_urb(usb, urb);
+ usb_free_urb(urb);
tx_dec_submitted_urbs(usb);
return;
resubmit:
+ usb_anchor_urb(urb, &tx->submitted);
r = usb_submit_urb(urb, GFP_ATOMIC);
if (r) {
+ usb_unanchor_urb(urb);
dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
goto free_urb;
}
@@ -958,8 +914,14 @@ int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
int r;
struct usb_device *udev = zd_usb_to_usbdev(usb);
struct urb *urb;
+ struct zd_usb_tx *tx = &usb->tx;
- urb = alloc_tx_urb(usb);
+ if (!atomic_read(&tx->enabled)) {
+ r = -ENOENT;
+ goto out;
+ }
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
if (!urb) {
r = -ENOMEM;
goto out;
@@ -968,13 +930,16 @@ int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
skb->data, skb->len, tx_urb_complete, skb);
+ usb_anchor_urb(urb, &tx->submitted);
r = usb_submit_urb(urb, GFP_ATOMIC);
- if (r)
+ if (r) {
+ usb_unanchor_urb(urb);
goto error;
+ }
tx_inc_submitted_urbs(usb);
return 0;
error:
- free_tx_urb(usb, urb);
+ usb_free_urb(urb);
out:
return r;
}
@@ -1005,9 +970,9 @@ static inline void init_usb_tx(struct zd_usb *usb)
{
struct zd_usb_tx *tx = &usb->tx;
spin_lock_init(&tx->lock);
- tx->enabled = 0;
+ atomic_set(&tx->enabled, 0);
tx->stopped = 0;
- INIT_LIST_HEAD(&tx->free_urb_list);
+ init_usb_anchor(&tx->submitted);
tx->submitted_urbs = 0;
}
@@ -1240,6 +1205,7 @@ static void disconnect(struct usb_interface *intf)
ieee80211_unregister_hw(hw);
/* Just in case something has gone wrong! */
+ zd_usb_disable_tx(usb);
zd_usb_disable_rx(usb);
zd_usb_disable_int(usb);
diff --git a/drivers/net/wireless/zd1211rw/zd_usb.h b/drivers/net/wireless/zd1211rw/zd_usb.h
index 1b1655c..233ce82 100644
--- a/drivers/net/wireless/zd1211rw/zd_usb.h
+++ b/drivers/net/wireless/zd1211rw/zd_usb.h
@@ -184,18 +184,18 @@ struct zd_usb_rx {
/**
* struct zd_usb_tx - structure used for transmitting frames
+ * @enabled: atomic enabled flag, indicates whether tx is enabled
* @lock: lock for transmission
- * @free_urb_list: list of free URBs, contains all the URBs, which can be used
+ * @submitted: anchor for URBs sent to device
* @submitted_urbs: atomic integer that counts the URBs having sent to the
* device, which haven't been completed
- * @enabled: enabled flag, indicates whether tx is enabled
* @stopped: indicates whether higher level tx queues are stopped
*/
struct zd_usb_tx {
+ atomic_t enabled;
spinlock_t lock;
- struct list_head free_urb_list;
+ struct usb_anchor submitted;
int submitted_urbs;
- int enabled;
int stopped;
};
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
