diff --git a/sound/sound_core.c b/sound/sound_core.c
index 46daca1..dcfc1d5 100644
--- a/sound/sound_core.c
+++ b/sound/sound_core.c
@@ -37,6 +37,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/fs.h>
@@ -464,6 +465,8 @@
 	struct sound_unit *s;
 	const struct file_operations *new_fops = NULL;
 
+	lock_kernel ();
+
 	chain=unit&0x0F;
 	if(chain==4 || chain==5)	/* dsp/audio/dsp16 */
 	{
@@ -511,9 +514,11 @@
 			file->f_op = fops_get(old_fops);
 		}
 		fops_put(old_fops);
+		unlock_kernel();
 		return err;
 	}
 	spin_unlock(&sound_loader_lock);
+	unlock_kernel();
 	return -ENODEV;
 }