diff options
author | Stanislav Yakovlev <stas.yakovlev@gmail.com> | 2012-04-19 15:55:09 -0400 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2012-05-11 13:14:53 +0100 |
commit | 12427fbf470faaf535915f4efc878eb46cb74c8c (patch) | |
tree | cb07f9b144ba539f1a003ca0e43dfd4c126194d2 /drivers | |
parent | b110a7c55ab6ad4dc953396236451ff885326e5b (diff) |
ipw2200: Fix race condition in the command completion acknowledge
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 <stas.yakovlev@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/wireless/ipw2x00/ipw2200.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c b/drivers/net/wireless/ipw2x00/ipw2200.c index 99a710dfe771..827889bb05ab 100644 --- a/drivers/net/wireless/ipw2x00/ipw2200.c +++ b/drivers/net/wireless/ipw2x00/ipw2200.c @@ -2183,6 +2183,7 @@ 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) { @@ -2224,10 +2225,20 @@ 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) { |