1 files changed, 56 insertions, 13 deletions

diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index cc0a789f09ae..bc6950a5740f 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -293,14 +293,22 @@ static int dvb_frontend_get_event(struct dvb_frontend *fe,
 	}
 
 	if (events->eventw == events->eventr) {
-		int ret;
+		struct wait_queue_entry wait;
+		int ret = 0;
 
 		if (flags & O_NONBLOCK)
 			return -EWOULDBLOCK;
 
-		ret = wait_event_interruptible(events->wait_queue,
-					       dvb_frontend_test_event(fepriv, events));
-
+		init_waitqueue_entry(&wait, current);
+		add_wait_queue(&events->wait_queue, &wait);
+		while (!dvb_frontend_test_event(fepriv, events)) {
+			wait_woken(&wait, TASK_INTERRUPTIBLE, 0);
+			if (signal_pending(current)) {
+				ret = -ERESTARTSYS;
+				break;
+			}
+		}
+		remove_wait_queue(&events->wait_queue, &wait);
 		if (ret < 0)
 			return ret;
 	}
@@ -809,15 +817,26 @@ static void dvb_frontend_stop(struct dvb_frontend *fe)
 
 	dev_dbg(fe->dvb->device, "%s:\n", __func__);
 
+	mutex_lock(&fe->remove_mutex);
+
 	if (fe->exit != DVB_FE_DEVICE_REMOVED)
 		fe->exit = DVB_FE_NORMAL_EXIT;
 	mb();
 
-	if (!fepriv->thread)
+	if (!fepriv->thread) {
+		mutex_unlock(&fe->remove_mutex);
 		return;
+	}
 
 	kthread_stop(fepriv->thread);
 
+	mutex_unlock(&fe->remove_mutex);
+
+	if (fepriv->dvbdev->users < -1) {
+		wait_event(fepriv->dvbdev->wait_queue,
+			   fepriv->dvbdev->users == -1);
+	}
+
 	sema_init(&fepriv->sem, 1);
 	fepriv->state = FESTATE_IDLE;
 
@@ -2761,9 +2780,13 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
 	struct dvb_adapter *adapter = fe->dvb;
 	int ret;
 
+	mutex_lock(&fe->remove_mutex);
+
 	dev_dbg(fe->dvb->device, "%s:\n", __func__);
-	if (fe->exit == DVB_FE_DEVICE_REMOVED)
-		return -ENODEV;
+	if (fe->exit == DVB_FE_DEVICE_REMOVED) {
+		ret = -ENODEV;
+		goto err_remove_mutex;
+	}
 
 	if (adapter->mfe_shared == 2) {
 		mutex_lock(&adapter->mfe_lock);
@@ -2771,7 +2794,8 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
 			if (adapter->mfe_dvbdev &&
 			    !adapter->mfe_dvbdev->writers) {
 				mutex_unlock(&adapter->mfe_lock);
-				return -EBUSY;
+				ret = -EBUSY;
+				goto err_remove_mutex;
 			}
 			adapter->mfe_dvbdev = dvbdev;
 		}
@@ -2794,8 +2818,10 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
 			while (mferetry-- && (mfedev->users != -1 ||
 					      mfepriv->thread)) {
 				if (msleep_interruptible(500)) {
-					if (signal_pending(current))
-						return -EINTR;
+					if (signal_pending(current)) {
+						ret = -EINTR;
+						goto err_remove_mutex;
+					}
 				}
 			}
 
@@ -2807,7 +2833,8 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
 				if (mfedev->users != -1 ||
 				    mfepriv->thread) {
 					mutex_unlock(&adapter->mfe_lock);
-					return -EBUSY;
+					ret = -EBUSY;
+					goto err_remove_mutex;
 				}
 				adapter->mfe_dvbdev = dvbdev;
 			}
@@ -2866,6 +2893,8 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
 
 	if (adapter->mfe_shared)
 		mutex_unlock(&adapter->mfe_lock);
+
+	mutex_unlock(&fe->remove_mutex);
 	return ret;
 
 err3:
@@ -2887,6 +2916,9 @@ err1:
 err0:
 	if (adapter->mfe_shared)
 		mutex_unlock(&adapter->mfe_lock);
+
+err_remove_mutex:
+	mutex_unlock(&fe->remove_mutex);
 	return ret;
 }
 
@@ -2897,6 +2929,8 @@ static int dvb_frontend_release(struct inode *inode, struct file *file)
 	struct dvb_frontend_private *fepriv = fe->frontend_priv;
 	int ret;
 
+	mutex_lock(&fe->remove_mutex);
+
 	dev_dbg(fe->dvb->device, "%s:\n", __func__);
 
 	if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
@@ -2918,10 +2952,18 @@ static int dvb_frontend_release(struct inode *inode, struct file *file)
 		}
 		mutex_unlock(&fe->dvb->mdev_lock);
 #endif
-		if (fe->exit != DVB_FE_NO_EXIT)
-			wake_up(&dvbdev->wait_queue);
 		if (fe->ops.ts_bus_ctrl)
 			fe->ops.ts_bus_ctrl(fe, 0);
+
+		if (fe->exit != DVB_FE_NO_EXIT) {
+			mutex_unlock(&fe->remove_mutex);
+			wake_up(&dvbdev->wait_queue);
+		} else {
+			mutex_unlock(&fe->remove_mutex);
+		}
+
+	} else {
+		mutex_unlock(&fe->remove_mutex);
 	}
 
 	dvb_frontend_put(fe);
@@ -3022,6 +3064,7 @@ int dvb_register_frontend(struct dvb_adapter *dvb,
 	fepriv = fe->frontend_priv;
 
 	kref_init(&fe->refcount);
+	mutex_init(&fe->remove_mutex);
 
 	/*
 	 * After initialization, there need to be two references: one