Return-path: Received: from mail-ie0-f174.google.com ([209.85.223.174]:47934 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754544Ab2IHCDr (ORCPT ); Fri, 7 Sep 2012 22:03:47 -0400 Received: by ieje11 with SMTP id e11so210449iej.19 for ; Fri, 07 Sep 2012 19:03:47 -0700 (PDT) Message-ID: <504AA77F.2010906@lwfinger.net> (sfid-20120908_040352_235354_7DA6B6CD) Date: Fri, 07 Sep 2012 21:03:43 -0500 From: Larry Finger MIME-Version: 1.0 To: Wei Yongjun CC: lauro.venancio@openbossa.org, aloisio.almeida@openbossa.org, sameo@linux.intel.com, yongjun_wei@trendmicro.com.cn, linux-wireless@vger.kernel.org Subject: Re: [PATCH v2] NFC: pn544_hci: move the dereference below the NULL test References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 09/07/2012 08:53 PM, Wei Yongjun wrote: > From: Wei Yongjun > > The dereference should be moved below the NULL test. > > spatch with a semantic match is used to found this. > (http://coccinelle.lip6.fr/) > > Signed-off-by: Wei Yongjun > --- > drivers/nfc/pn544_hci.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/nfc/pn544_hci.c b/drivers/nfc/pn544_hci.c > index aa71807..7b20f2d 100644 > --- a/drivers/nfc/pn544_hci.c > +++ b/drivers/nfc/pn544_hci.c > @@ -341,13 +341,14 @@ flush: > static irqreturn_t pn544_hci_irq_thread_fn(int irq, void *dev_id) > { > struct pn544_hci_info *info = dev_id; > - struct i2c_client *client = info->i2c_dev; > + struct i2c_client *client; > struct sk_buff *skb = NULL; > int r; > > BUG_ON(!info); > BUG_ON(irq != info->i2c_dev->irq); > > + client = info->i2c_dev; As long as you are reworking this section, doesn't BUG_ON seem a little harsh? I do not think the kernel should ever be crashed because a non-essential driver is messed up. As the patch would be a totally different change, it should be a new submission, but I think each of these conditions should trigger a WARN_ON_ONCE, and return IRQ_NONE when they occur. Larry > dev_dbg(&client->dev, "IRQ\n"); > > if (info->hard_fault != 0) > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >