diff --git a/[refs] b/[refs]
index afe244d92a9a..fcf143a68fb3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fac533c2505b39faf30492cd3f0844c0da51c75c
+refs/heads/master: 5214b729e1c2dc3af8f55e6c4c548844c3bea0f5
diff --git a/trunk/fs/afs/cell.c b/trunk/fs/afs/cell.c
index 970d38f30565..788865df1bc9 100644
--- a/trunk/fs/afs/cell.c
+++ b/trunk/fs/afs/cell.c
@@ -127,14 +127,20 @@ struct afs_cell *afs_cell_create(const char *name, char *vllist)
 
 	_enter("%s,%s", name, vllist);
 
+	down_write(&afs_cells_sem);
+	read_lock(&afs_cells_lock);
+	list_for_each_entry(cell, &afs_cells, link) {
+		if (strcasecmp(cell->name, name) == 0)
+			goto duplicate_name;
+	}
+	read_unlock(&afs_cells_lock);
+
 	cell = afs_cell_alloc(name, vllist);
 	if (IS_ERR(cell)) {
 		_leave(" = %ld", PTR_ERR(cell));
 		return cell;
 	}
 
-	down_write(&afs_cells_sem);
-
 	/* add a proc directory for this cell */
 	ret = afs_proc_cell_setup(cell);
 	if (ret < 0)
@@ -167,6 +173,11 @@ struct afs_cell *afs_cell_create(const char *name, char *vllist)
 	kfree(cell);
 	_leave(" = %d", ret);
 	return ERR_PTR(ret);
+
+duplicate_name:
+	read_unlock(&afs_cells_lock);
+	up_write(&afs_cells_sem);
+	return ERR_PTR(-EEXIST);
 }
 
 /*