mei: bus: stop wait for read during cl state transition
authorTomas Winkler <tomas.winkler@intel.com>
Mon, 2 Sep 2013 10:29:46 +0000 (13:29 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 26 Sep 2013 20:56:53 +0000 (13:56 -0700)
Bus layer omitted check for client state transition while waiting
for read completion
The client state transition may occur for example as result
of firmware initiated reset

Add mei_cl_is_transitioning wrapper to reduce the code
repetition.:

Cc: <stable@vger.kernel.org> # 3.9+
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/misc/mei/bus.c
drivers/misc/mei/client.h
drivers/misc/mei/main.c

index 6d0282c..cd2033c 100644 (file)
@@ -297,10 +297,13 @@ int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 
        if (cl->reading_state != MEI_READ_COMPLETE &&
            !waitqueue_active(&cl->rx_wait)) {
+
                mutex_unlock(&dev->device_lock);
 
                if (wait_event_interruptible(cl->rx_wait,
-                               (MEI_READ_COMPLETE == cl->reading_state))) {
+                               cl->reading_state == MEI_READ_COMPLETE  ||
+                               mei_cl_is_transitioning(cl))) {
+
                        if (signal_pending(current))
                                return -EINTR;
                        return -ERESTARTSYS;
index 9eb031e..892cc42 100644 (file)
@@ -90,6 +90,12 @@ static inline bool mei_cl_is_connected(struct mei_cl *cl)
                cl->dev->dev_state == MEI_DEV_ENABLED &&
                cl->state == MEI_FILE_CONNECTED);
 }
+static inline bool mei_cl_is_transitioning(struct mei_cl *cl)
+{
+       return (MEI_FILE_INITIALIZING == cl->state ||
+               MEI_FILE_DISCONNECTED == cl->state ||
+               MEI_FILE_DISCONNECTING == cl->state);
+}
 
 bool mei_cl_is_other_connecting(struct mei_cl *cl);
 int mei_cl_disconnect(struct mei_cl *cl);
index 173ff09..cabeddd 100644 (file)
@@ -249,19 +249,16 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
                mutex_unlock(&dev->device_lock);
 
                if (wait_event_interruptible(cl->rx_wait,
-                       (MEI_READ_COMPLETE == cl->reading_state ||
-                        MEI_FILE_INITIALIZING == cl->state ||
-                        MEI_FILE_DISCONNECTED == cl->state ||
-                        MEI_FILE_DISCONNECTING == cl->state))) {
+                               MEI_READ_COMPLETE == cl->reading_state ||
+                               mei_cl_is_transitioning(cl))) {
+
                        if (signal_pending(current))
                                return -EINTR;
                        return -ERESTARTSYS;
                }
 
                mutex_lock(&dev->device_lock);
-               if (MEI_FILE_INITIALIZING == cl->state ||
-                   MEI_FILE_DISCONNECTED == cl->state ||
-                   MEI_FILE_DISCONNECTING == cl->state) {
+               if (mei_cl_is_transitioning(cl)) {
                        rets = -EBUSY;
                        goto out;
                }