From: Julia Lawall <julia@diku.dk>
Date: Sun, 19 Jul 2009 06:13:04 +0000 (+0000)
Subject: drivers/net: Move a dereference below a NULL test
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0021195c40326ac4702faf28c32accd91b331641;p=linux-beck.git

drivers/net: Move a dereference below a NULL test

If the NULL test is necessary, then the dereferences should be moved below
the NULL test.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
expression E,E1;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
  ... when != E=E1
      when != i
  BUG_ON (E == NULL||...);
+ i = E->fld;
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/ibm_newemac/rgmii.c b/drivers/net/ibm_newemac/rgmii.c
index 1d5379de6900..8d76cb89dbd6 100644
--- a/drivers/net/ibm_newemac/rgmii.c
+++ b/drivers/net/ibm_newemac/rgmii.c
@@ -188,11 +188,12 @@ void rgmii_put_mdio(struct of_device *ofdev, int input)
 void rgmii_detach(struct of_device *ofdev, int input)
 {
 	struct rgmii_instance *dev = dev_get_drvdata(&ofdev->dev);
-	struct rgmii_regs __iomem *p = dev->base;
-
-	mutex_lock(&dev->lock);
+	struct rgmii_regs __iomem *p;
 
 	BUG_ON(!dev || dev->users == 0);
+	p = dev->base;
+
+	mutex_lock(&dev->lock);
 
 	RGMII_DBG(dev, "detach(%d)" NL, input);