commit: 2ae1b8b35faba31a59b153cbad07f9c15de99740
From: Paul Fox <[email protected]>
Date: Mon, 9 May 2011 10:40:42 +0100
Subject: [PATCH] libertas: fix cmdpendingq locking

We occasionally see list corruption using libertas.

While we haven't been able to diagnose this precisely, we have spotted
a possible cause: cmdpendingq is generally modified with driver_lock
held. However, there are a couple of points where this is not the case.

Fix up those operations to execute under the lock, it seems like
the correct thing to do and will hopefully improve the situation.

Signed-off-by: Paul Fox <[email protected]>
Signed-off-by: Daniel Drake <[email protected]>
Acked-by: Dan Williams <[email protected]>
Cc: [email protected]
Signed-off-by: John W. Linville <[email protected]>
---
 drivers/net/wireless/libertas/cmd.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/libertas/cmd.c 
b/drivers/net/wireless/libertas/cmd.c
index 7e8a658..f3ac624 100644
--- a/drivers/net/wireless/libertas/cmd.c
+++ b/drivers/net/wireless/libertas/cmd.c
@@ -1339,8 +1339,8 @@ int lbs_execute_next_command(struct lbs_private *priv)
                                    cpu_to_le16(PS_MODE_ACTION_EXIT_PS)) {
                                        lbs_deb_host(
                                               "EXEC_NEXT_CMD: ignore ENTER_PS 
cmd\n");
-                                       list_del(&cmdnode->list);
                                        spin_lock_irqsave(&priv->driver_lock, 
flags);
+                                       list_del(&cmdnode->list);
                                        lbs_complete_command(priv, cmdnode, 0);
                                        
spin_unlock_irqrestore(&priv->driver_lock, flags);
 
@@ -1352,8 +1352,8 @@ int lbs_execute_next_command(struct lbs_private *priv)
                                    (priv->psstate == PS_STATE_PRE_SLEEP)) {
                                        lbs_deb_host(
                                               "EXEC_NEXT_CMD: ignore EXIT_PS 
cmd in sleep\n");
-                                       list_del(&cmdnode->list);
                                        spin_lock_irqsave(&priv->driver_lock, 
flags);
+                                       list_del(&cmdnode->list);
                                        lbs_complete_command(priv, cmdnode, 0);
                                        
spin_unlock_irqrestore(&priv->driver_lock, flags);
                                        priv->needtowakeup = 1;
@@ -1366,7 +1366,9 @@ int lbs_execute_next_command(struct lbs_private *priv)
                                       "EXEC_NEXT_CMD: sending EXIT_PS\n");
                        }
                }
+               spin_lock_irqsave(&priv->driver_lock, flags);
                list_del(&cmdnode->list);
+               spin_unlock_irqrestore(&priv->driver_lock, flags);
                lbs_deb_host("EXEC_NEXT_CMD: sending command 0x%04x\n",
                            le16_to_cpu(cmd->command));
                lbs_submit_command(priv, cmdnode);

_______________________________________________
stable mailing list
[email protected]
http://linux.kernel.org/mailman/listinfo/stable

Reply via email to