1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/staging/frontier/alphatrack.c b/drivers/staging/frontier/alphatrack.c
index 15aed87fe1bb..e2f82f0dbad8 100644
--- a/drivers/staging/frontier/alphatrack.c
+++ b/drivers/staging/frontier/alphatrack.c
@@ -41,6 +41,7 @@
 #include <linux/mutex.h>
 
 #include <linux/uaccess.h>
+#include <linux/smp_lock.h>
 #include <linux/input.h>
 #include <linux/usb.h>
 #include <linux/poll.h>
@@ -325,6 +326,7 @@ static int usb_alphatrack_open(struct inode *inode, struct file *file)
 	int retval = 0;
 	struct usb_interface *interface;
 
+	lock_kernel();
 	nonseekable_open(inode, file);
 	subminor = iminor(inode);
 
@@ -394,6 +396,7 @@ unlock_exit:
 
 unlock_disconnect_exit:
 	mutex_unlock(&disconnect_mutex);
+	unlock_kernel();
 
 	return retval;
 }