From: Jonathan Corbet <corbet@lwn.net>
Date: Fri, 16 May 2008 19:50:20 +0000 (-0600)
Subject: xilinx icap: BKL pushdown
X-Git-Tag: v2.6.27-rc1~1103^2~105
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f4943db14f5071ecbf7ca76722e59a2fd22bda4d;p=linux-2.6

xilinx icap: BKL pushdown

Add explicit lock_kernel() calls to hwicap_open() even though the existing
locking looks adequate.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
---

diff --git a/drivers/char/xilinx_hwicap/xilinx_hwicap.c b/drivers/char/xilinx_hwicap/xilinx_hwicap.c
index 3edf1fc129..1e1b81e57c 100644
--- a/drivers/char/xilinx_hwicap/xilinx_hwicap.c
+++ b/drivers/char/xilinx_hwicap/xilinx_hwicap.c
@@ -85,6 +85,7 @@
 #include <linux/poll.h>
 #include <linux/proc_fs.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <linux/sysctl.h>
 #include <linux/version.h>
 #include <linux/fs.h>
@@ -504,11 +505,12 @@ static int hwicap_open(struct inode *inode, struct file *file)
 	struct hwicap_drvdata *drvdata;
 	int status;
 
+	lock_kernel();
 	drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
 
 	status = mutex_lock_interruptible(&drvdata->sem);
 	if (status)
-		return status;
+		goto out;
 
 	if (drvdata->is_open) {
 		status = -EBUSY;
@@ -528,6 +530,8 @@ static int hwicap_open(struct inode *inode, struct file *file)
 
  error:
 	mutex_unlock(&drvdata->sem);
+ out:
+	unlock_kernel();
 	return status;
 }