From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754608AbdGUQvR (ORCPT ); Fri, 21 Jul 2017 12:51:17 -0400 Received: from mga14.intel.com ([192.55.52.115]:31957 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753792AbdGUQvO (ORCPT ); Fri, 21 Jul 2017 12:51:14 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,391,1496127600"; d="scan'208";a="1198037791" Subject: Re: [PATCH] dmaengine: ioatdma: Fix error handling path in 'ioat_dma_self_test()' To: Vinod Koul Cc: "wharms@bfs.de" , Christophe JAILLET , "Williams, Dan J" , "dmaengine@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "kernel-janitors@vger.kernel.org" References: <20170719221648.30253-1-christophe.jaillet@wanadoo.fr> <59705A93.2090305@bfs.de> <20170721075754.GP3053@localhost> From: Dave Jiang Message-ID: Date: Fri, 21 Jul 2017 09:50:46 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170721075754.GP3053@localhost> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/21/2017 12:57 AM, Vinod Koul wrote: > On Thu, Jul 20, 2017 at 09:56:45AM -0700, Dave Jiang wrote: >> >> >> On 07/20/2017 12:24 AM, walter harms wrote: >>> >>> >>> Am 20.07.2017 00:16, schrieb Christophe JAILLET: >>>> If the 'memcmp' fails, free allocated resources as done in all other >>>> error handling paths. >>>> >>>> Signed-off-by: Christophe JAILLET >>>> --- >>>> Please review carefully, this patch looks "too obvious" to me! >>>> --- >>>> drivers/dma/ioat/init.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c >>>> index ed8ed1192775..948fc1f8fb5c 100644 >>>> --- a/drivers/dma/ioat/init.c >>>> +++ b/drivers/dma/ioat/init.c >>>> @@ -390,7 +390,7 @@ static int ioat_dma_self_test(struct ioatdma_device *ioat_dma) >>>> if (memcmp(src, dest, IOAT_TEST_SIZE)) { >>>> dev_err(dev, "Self-test copy failed compare, disabling\n"); >>>> err = -ENODEV; >>>> - goto free_resources; >>>> + goto unmap_dma; >>>> } >>>> >>>> unmap_dma: >>> >>> ^^^^^^^^^^ >>> >>> >>> is the goto needed at all ? >> >> It's not. However, it may be better to stay there if we happen to add >> additional code after the if block later on and guard against mistakes. >> At least IMO. > > Then lets remove it please, there is no place for dead code, if we need it > people can add it as part of the changes they introduce.. > I have no strong opinion in this Christophe. I have seen mistakes and bugs introduced because of these special optimizations. I've said my piece and Vinod is for removing it so I'll defer to him.