V4L/DVB (4995): Vivi: fix kthread_run() error check

The return value of kthread_run() should be checked by IS_ERR().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/vivi.c b/drivers/media/video/vivi.c
index 3cead24..bacb311 100644
--- a/drivers/media/video/vivi.c
+++ b/drivers/media/video/vivi.c
@@ -535,9 +535,9 @@
 
 	dma_q->kthread = kthread_run(vivi_thread, dma_q, "vivi");
 
-	if (dma_q->kthread == NULL) {
+	if (IS_ERR(dma_q->kthread)) {
 		printk(KERN_ERR "vivi: kernel_thread() failed\n");
-		return -EINVAL;
+		return PTR_ERR(dma_q->kthread);
 	}
 	dprintk(1,"returning from %s\n",__FUNCTION__);
 	return 0;