From 3f58ea07551e7090ed5f3079d9b9d375f0e3f6b0 Mon Sep 17 00:00:00 2001
From: Jonathan Corbet <corbet@lwn.net>
Date: Thu, 15 May 2008 10:10:37 -0600
Subject: [PATCH] --- yaml --- r: 100275 b: refs/heads/master c:
 6071239ef1947914892601e36785c7b1cf8b7dd4 h: refs/heads/master i:   100273:
 58d519f39214809cc10aff210261d431f44dc4d6   100271:
 42ae260b14a59bb5d26dc303c6ef96dfcbfd487f v: v3

---
 [refs]                      |  2 +-
 trunk/drivers/mtd/mtdchar.c | 22 ++++++++++++++++------
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 83587f578b8f..2e6ae4ff1075 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ea2959a2972410f15155a015df74ce77ac79f8b8
+refs/heads/master: 6071239ef1947914892601e36785c7b1cf8b7dd4
diff --git a/trunk/drivers/mtd/mtdchar.c b/trunk/drivers/mtd/mtdchar.c
index 5d3ac512ce16..129d429cd2da 100644
--- a/trunk/drivers/mtd/mtdchar.c
+++ b/trunk/drivers/mtd/mtdchar.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/smp_lock.h>
 
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/compatmac.h>
@@ -86,6 +87,7 @@ static int mtd_open(struct inode *inode, struct file *file)
 {
 	int minor = iminor(inode);
 	int devnum = minor >> 1;
+	int ret = 0;
 	struct mtd_info *mtd;
 	struct mtd_file_info *mfi;
 
@@ -98,31 +100,39 @@ static int mtd_open(struct inode *inode, struct file *file)
 	if ((file->f_mode & 2) && (minor & 1))
 		return -EACCES;
 
+	lock_kernel();
 	mtd = get_mtd_device(NULL, devnum);
 
-	if (IS_ERR(mtd))
-		return PTR_ERR(mtd);
+	if (IS_ERR(mtd)) {
+		ret = PTR_ERR(mtd);
+		goto out;
+	}
 
 	if (MTD_ABSENT == mtd->type) {
 		put_mtd_device(mtd);
-		return -ENODEV;
+		ret = -ENODEV;
+		goto out;
 	}
 
 	/* You can't open it RW if it's not a writeable device */
 	if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
 		put_mtd_device(mtd);
-		return -EACCES;
+		ret = -EACCES;
+		goto out;
 	}
 
 	mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 	if (!mfi) {
 		put_mtd_device(mtd);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto out;
 	}
 	mfi->mtd = mtd;
 	file->private_data = mfi;
 
-	return 0;
+out:
+	unlock_kernel();
+	return ret;
 } /* mtd_open */
 
 /*====================================================================*/