diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 4a1b9e74..05d5ef1 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -9,7 +9,7 @@
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include <linux/skbuff.h>
 #include "aoe.h"
 
@@ -37,6 +37,7 @@
 	char *msg;
 };
 
+static DEFINE_MUTEX(aoechr_mutex);
 static struct ErrMsg emsgs[NMSG];
 static int emsgs_head_idx, emsgs_tail_idx;
 static struct completion emsgs_comp;
@@ -183,16 +184,16 @@
 {
 	int n, i;
 
-	lock_kernel();
+	mutex_lock(&aoechr_mutex);
 	n = iminor(inode);
 	filp->private_data = (void *) (unsigned long) n;
 
 	for (i = 0; i < ARRAY_SIZE(chardevs); ++i)
 		if (chardevs[i].minor == n) {
-			unlock_kernel();
+			mutex_unlock(&aoechr_mutex);
 			return 0;
 		}
-	unlock_kernel();
+	mutex_unlock(&aoechr_mutex);
 	return -EINVAL;
 }