diff --git a/[refs] b/[refs]
index 6cb0def566fd..217ca3a149ca 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cddf63d99d0d145f18b293c3d0de4af7dab2a922
+refs/heads/master: 28fbbf491368c9491461ca492e13862da1b49180
diff --git a/trunk/drivers/sbus/char/jsflash.c b/trunk/drivers/sbus/char/jsflash.c
index 4b7079fdc10c..2bec9ccc0293 100644
--- a/trunk/drivers/sbus/char/jsflash.c
+++ b/trunk/drivers/sbus/char/jsflash.c
@@ -27,6 +27,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/smp_lock.h>
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/miscdevice.h>
@@ -417,11 +418,17 @@ static int jsf_mmap(struct file * file, struct vm_area_struct * vma)
 
 static int jsf_open(struct inode * inode, struct file * filp)
 {
-
-	if (jsf0.base == 0) return -ENXIO;
-	if (test_and_set_bit(0, (void *)&jsf0.busy) != 0)
+	lock_kernel();
+	if (jsf0.base == 0) {
+		unlock_kernel();
+		return -ENXIO;
+	}
+	if (test_and_set_bit(0, (void *)&jsf0.busy) != 0) {
+		unlock_kernel();
 		return -EBUSY;
+	}
 
+	unlock_kernel();
 	return 0;	/* XXX What security? */
 }