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authorAmitkumar Karwar <akarwar@marvell.com>2013-03-16 05:47:05 +0400
committerJohn W. Linville <linville@tuxdriver.com>2013-03-18 23:20:36 +0400
commit00d7ea11ff0783e24fe70778f3141270b561aaa1 (patch)
tree7b1275391f76d2202dc884c9a2b53e0715127c3b /drivers
parent01d4ab96d2e7fceaad204e5a8710ce34e229b8c5 (diff)
downloadlinux-00d7ea11ff0783e24fe70778f3141270b561aaa1.tar.xz
mwifiex: fix race when queuing commands
Running the following script repeatedly on XO-4 with SD8787 produces command timeout and system lockup. insmod mwifiex_sdio.ko sleep 1 ifconfig eth0 up iwlist eth0 scan & sleep 0.5 rmmod mwifiex_sdio mwifiex_send_cmd_async() is called for sync as well as async commands. (mwifiex_send_cmd_sync() internally calls it for sync command.) "adapter->cmd_queued" gets filled inside mwifiex_send_cmd_async() routine for both types of commands. But it is used only for sync commands in mwifiex_wait_queue_complete(). This could lead to a race when two threads try to queue a sync command with another sync/async command simultaneously. Get rid of global variable and pass command node as a parameter to mwifiex_wait_queue_complete() to fix the problem. Cc: <stable@vger.kernel.org> # 3.8 Reported-by: Daniel Drake <dsd@laptop.org> Tested-by: Daniel Drake <dsd@laptop.org> Tested-by: Marco Cesarano <marco@marvell.com> Signed-off-by: Amitkumar Karwar <akarwar@marvell.com> Signed-off-by: Bing Zhao <bzhao@marvell.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/wireless/mwifiex/cmdevt.c5
-rw-r--r--drivers/net/wireless/mwifiex/main.h4
-rw-r--r--drivers/net/wireless/mwifiex/scan.c8
-rw-r--r--drivers/net/wireless/mwifiex/sta_ioctl.c10
4 files changed, 10 insertions, 17 deletions
diff --git a/drivers/net/wireless/mwifiex/cmdevt.c b/drivers/net/wireless/mwifiex/cmdevt.c
index 20a6c5555873..2ffabddbcfca 100644
--- a/drivers/net/wireless/mwifiex/cmdevt.c
+++ b/drivers/net/wireless/mwifiex/cmdevt.c
@@ -484,8 +484,6 @@ int mwifiex_send_cmd_sync(struct mwifiex_private *priv, uint16_t cmd_no,
ret = mwifiex_send_cmd_async(priv, cmd_no, cmd_action, cmd_oid,
data_buf);
- if (!ret)
- ret = mwifiex_wait_queue_complete(adapter);
return ret;
}
@@ -588,9 +586,10 @@ int mwifiex_send_cmd_async(struct mwifiex_private *priv, uint16_t cmd_no,
if (cmd_no == HostCmd_CMD_802_11_SCAN) {
mwifiex_queue_scan_cmd(priv, cmd_node);
} else {
- adapter->cmd_queued = cmd_node;
mwifiex_insert_cmd_to_pending_q(adapter, cmd_node, true);
queue_work(adapter->workqueue, &adapter->main_work);
+ if (cmd_node->wait_q_enabled)
+ ret = mwifiex_wait_queue_complete(adapter, cmd_node);
}
return ret;
diff --git a/drivers/net/wireless/mwifiex/main.h b/drivers/net/wireless/mwifiex/main.h
index 553adfb0aa81..7035ade9af74 100644
--- a/drivers/net/wireless/mwifiex/main.h
+++ b/drivers/net/wireless/mwifiex/main.h
@@ -723,7 +723,6 @@ struct mwifiex_adapter {
u16 cmd_wait_q_required;
struct mwifiex_wait_queue cmd_wait_q;
u8 scan_wait_q_woken;
- struct cmd_ctrl_node *cmd_queued;
spinlock_t queue_lock; /* lock for tx queues */
struct completion fw_load;
u8 country_code[IEEE80211_COUNTRY_STRING_LEN];
@@ -1018,7 +1017,8 @@ int mwifiex_request_set_multicast_list(struct mwifiex_private *priv,
struct mwifiex_multicast_list *mcast_list);
int mwifiex_copy_mcast_addr(struct mwifiex_multicast_list *mlist,
struct net_device *dev);
-int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter);
+int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter,
+ struct cmd_ctrl_node *cmd_queued);
int mwifiex_bss_start(struct mwifiex_private *priv, struct cfg80211_bss *bss,
struct cfg80211_ssid *req_ssid);
int mwifiex_cancel_hs(struct mwifiex_private *priv, int cmd_type);
diff --git a/drivers/net/wireless/mwifiex/scan.c b/drivers/net/wireless/mwifiex/scan.c
index bb60c2754a97..d215b4d3c51b 100644
--- a/drivers/net/wireless/mwifiex/scan.c
+++ b/drivers/net/wireless/mwifiex/scan.c
@@ -1388,10 +1388,13 @@ int mwifiex_scan_networks(struct mwifiex_private *priv,
list_del(&cmd_node->list);
spin_unlock_irqrestore(&adapter->scan_pending_q_lock,
flags);
- adapter->cmd_queued = cmd_node;
mwifiex_insert_cmd_to_pending_q(adapter, cmd_node,
true);
queue_work(adapter->workqueue, &adapter->main_work);
+
+ /* Perform internal scan synchronously */
+ if (!priv->scan_request)
+ mwifiex_wait_queue_complete(adapter, cmd_node);
} else {
spin_unlock_irqrestore(&adapter->scan_pending_q_lock,
flags);
@@ -1946,9 +1949,6 @@ int mwifiex_request_scan(struct mwifiex_private *priv,
/* Normal scan */
ret = mwifiex_scan_networks(priv, NULL);
- if (!ret)
- ret = mwifiex_wait_queue_complete(priv->adapter);
-
up(&priv->async_sem);
return ret;
diff --git a/drivers/net/wireless/mwifiex/sta_ioctl.c b/drivers/net/wireless/mwifiex/sta_ioctl.c
index 9f33c92c90f5..13100f8de3db 100644
--- a/drivers/net/wireless/mwifiex/sta_ioctl.c
+++ b/drivers/net/wireless/mwifiex/sta_ioctl.c
@@ -54,16 +54,10 @@ int mwifiex_copy_mcast_addr(struct mwifiex_multicast_list *mlist,
* This function waits on a cmd wait queue. It also cancels the pending
* request after waking up, in case of errors.
*/
-int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter)
+int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter,
+ struct cmd_ctrl_node *cmd_queued)
{
int status;
- struct cmd_ctrl_node *cmd_queued;
-
- if (!adapter->cmd_queued)
- return 0;
-
- cmd_queued = adapter->cmd_queued;
- adapter->cmd_queued = NULL;
dev_dbg(adapter->dev, "cmd pending\n");
atomic_inc(&adapter->cmd_pending);