From 6be2298a482f4078f90c11b021210a1ed176112a Mon Sep 17 00:00:00 2001
From: Jonathan Corbet <corbet@lwn.net>
Date: Thu, 15 May 2008 12:22:06 -0600
Subject: [PATCH] --- yaml --- r: 100289 b: refs/heads/master c:
 eb09d3d4ee09b25876db549b6d5221610216e105 h: refs/heads/master i:   100287:
 4c3e5c4ea9938fde7eb120ee67b454e1c0cb0b3a v: v3

---
 [refs]                  |  2 +-
 trunk/drivers/scsi/sg.c | 16 +++++++++++++---
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 3bb9e9b458b1..60a3c96b09b3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 04f4ac9d1bb8a9103609ce8e927f8e98826ce339
+refs/heads/master: eb09d3d4ee09b25876db549b6d5221610216e105
diff --git a/trunk/drivers/scsi/sg.c b/trunk/drivers/scsi/sg.c
index c9d7f721b9e2..4284625ed035 100644
--- a/trunk/drivers/scsi/sg.c
+++ b/trunk/drivers/scsi/sg.c
@@ -49,6 +49,7 @@ static int sg_version_num = 30534;	/* 2 digits for each component */
 #include <linux/delay.h>
 #include <linux/scatterlist.h>
 #include <linux/blktrace_api.h>
+#include <linux/smp_lock.h>
 
 #include "scsi.h"
 #include <scsi/scsi_dbg.h>
@@ -227,19 +228,26 @@ sg_open(struct inode *inode, struct file *filp)
 	int res;
 	int retval;
 
+	lock_kernel();
 	nonseekable_open(inode, filp);
 	SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 	sdp = sg_get_dev(dev);
-	if ((!sdp) || (!sdp->device))
+	if ((!sdp) || (!sdp->device)) {
+		unlock_kernel();
 		return -ENXIO;
-	if (sdp->detached)
+	}
+	if (sdp->detached) {
+		unlock_kernel();
 		return -ENODEV;
+	}
 
 	/* This driver's module count bumped by fops_get in <linux/fs.h> */
 	/* Prevent the device driver from vanishing while we sleep */
 	retval = scsi_device_get(sdp->device);
-	if (retval)
+	if (retval) {
+		unlock_kernel();
 		return retval;
+	}
 
 	if (!((flags & O_NONBLOCK) ||
 	      scsi_block_when_processing_errors(sdp->device))) {
@@ -295,10 +303,12 @@ sg_open(struct inode *inode, struct file *filp)
 		retval = -ENOMEM;
 		goto error_out;
 	}
+	unlock_kernel();
 	return 0;
 
       error_out:
 	scsi_device_put(sdp->device);
+	unlock_kernel();
 	return retval;
 }