Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751588AbaLQWf0 (ORCPT ); Wed, 17 Dec 2014 17:35:26 -0500 Received: from arroyo.ext.ti.com ([192.94.94.40]:49907 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751325AbaLQWfY (ORCPT ); Wed, 17 Dec 2014 17:35:24 -0500 Message-ID: <54920529.4080007@ti.com> Date: Wed, 17 Dec 2014 17:35:21 -0500 From: Murali Karicheri User-Agent: Mozilla/5.0 (X11; Linux i686; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Bjorn Helgaas CC: "linux-pci@vger.kernel.org" , Christopher Li , "linux-kernel@vger.kernel.org" Subject: Re: How to fix CHECK warning: testing a 'safe expression' ? References: <54907884.2040502@ti.com> <5491ACE6.4070108@ti.com> In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/17/2014 01:49 PM, Bjorn Helgaas wrote: > [+cc Christopher, linux-kernel (this doesn't sound like a PCI-specific > question)] > > On Wed, Dec 17, 2014 at 9:18 AM, Murali Karicheri wrote: >> I am trying to address CHECK warnings in my driver and wondering how to >> resolve 'warning: testing a 'safe expression' which appears when using >> IS_ERR_OR_NULL(foo) >> >> where foo is defined as >> >> struct foo_type *foo; >> >> The foo get assigned only NULL or ERR_PTR(error code). So I believe the >> usage is correct. But then how do I make the CHECK happy of its usage? >> >> I have tried a grep to check on the current usage of IS_ERR_OR_NULL() and >> found 276 of them causes this warning in the v3.18 version of the kernel >> that I am using >> >> $ grep -r "warning: testing a 'safe expression" * | wc -l >> 276 >> >> Can someone help me undestand what this means and how to fix the same? >> >> I run folling for CHECK >> >> make C=2 CF="-D__CHECK_ENDIAN__" CHECK=sparse > > If you can share your actual code or point to it in the tree, you > might get more specific help. > > Bjorn For example I get CHECK drivers/pci/host/pci-keystone.c include/linux/err.h:40:16: warning: testing a 'safe expression' Actually it is for IS_ERR_OR_NULL() call in the file which is the only one call in the file. -- Murali Karicheri Linux Kernel, Texas Instruments -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/