3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Stanislav Yakovlev <[email protected]>

commit dd447319895d0c0af423e483d9b63f84f3f8869a upstream.

Driver incorrectly validates command completion: instead of waiting
for a command to be acknowledged it continues execution.  Most of the
time driver gets acknowledge of the command completion in a tasklet
before it executes the next one. But sometimes it sends the next
command before it gets acknowledge for the previous one. In such a
case one of the following error messages appear in the log:

Failed to send SYSTEM_CONFIG: Already sending a command.
Failed to send ASSOCIATE: Already sending a command.
Failed to send TX_POWER: Already sending a command.

After that you need to reload the driver to get it working again.

This bug occurs during roaming (reported by Sam Varshavchik)
https://bugzilla.redhat.com/show_bug.cgi?id=738508
and machine booting (reported by Tom Gundersen and Mads Kiilerich)
https://bugs.archlinux.org/task/28097
https://bugzilla.redhat.com/show_bug.cgi?id=802106

This patch doesn't fix the delay issue during firmware load.
But at least device now works as usual after boot.

Signed-off-by: Stanislav Yakovlev <[email protected]>
Signed-off-by: John W. Linville <[email protected]>
Signed-off-by: Ben Hutchings <[email protected]>
---
 drivers/net/wireless/ipw2x00/ipw2200.c |   13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c 
b/drivers/net/wireless/ipw2x00/ipw2200.c
index 2b02257..1779db3 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.c
+++ b/drivers/net/wireless/ipw2x00/ipw2200.c
@@ -2191,6 +2191,7 @@ static int __ipw_send_cmd(struct ipw_priv *priv, struct 
host_cmd *cmd)
 {
        int rc = 0;
        unsigned long flags;
+       unsigned long now, end;
 
        spin_lock_irqsave(&priv->lock, flags);
        if (priv->status & STATUS_HCMD_ACTIVE) {
@@ -2232,10 +2233,20 @@ static int __ipw_send_cmd(struct ipw_priv *priv, struct 
host_cmd *cmd)
        }
        spin_unlock_irqrestore(&priv->lock, flags);
 
+       now = jiffies;
+       end = now + HOST_COMPLETE_TIMEOUT;
+again:
        rc = wait_event_interruptible_timeout(priv->wait_command_queue,
                                              !(priv->
                                                status & STATUS_HCMD_ACTIVE),
-                                             HOST_COMPLETE_TIMEOUT);
+                                             end - now);
+       if (rc < 0) {
+               now = jiffies;
+               if (time_before(now, end))
+                       goto again;
+               rc = 0;
+       }
+
        if (rc == 0) {
                spin_lock_irqsave(&priv->lock, flags);
                if (priv->status & STATUS_HCMD_ACTIVE) {
-- 
1.7.10



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