From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6424FC43613 for ; Mon, 24 Jun 2019 20:25:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35A1E20663 for ; Mon, 24 Jun 2019 20:25:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728163AbfFXUZu (ORCPT ); Mon, 24 Jun 2019 16:25:50 -0400 Received: from mga04.intel.com ([192.55.52.120]:25196 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726393AbfFXUZt (ORCPT ); Mon, 24 Jun 2019 16:25:49 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Jun 2019 13:25:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,413,1557212400"; d="scan'208";a="336613306" Received: from tthayer-hp-z620.an.intel.com (HELO [10.122.105.146]) ([10.122.105.146]) by orsmga005.jf.intel.com with ESMTP; 24 Jun 2019 13:25:48 -0700 Reply-To: thor.thayer@linux.intel.com Subject: Re: [PATCH] EDAC/altera: Silence an endian warning To: Dan Carpenter Cc: Borislav Petkov , Mauro Carvalho Chehab , James Morse , linux-edac@vger.kernel.org, kernel-janitors@vger.kernel.org References: <20190624134717.GA1754@mwanda> From: Thor Thayer Message-ID: <2baa5124-f0b0-a33e-256b-6a17867862c9@linux.intel.com> Date: Mon, 24 Jun 2019 15:27:55 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.1 MIME-Version: 1.0 In-Reply-To: <20190624134717.GA1754@mwanda> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org Hi Dan, On 6/24/19 8:47 AM, Dan Carpenter wrote: > Smatch complains that we're casting a u32 pointer to unsigned long. > > drivers/edac/altera_edac.c:1878 altr_edac_a10_irq_handler() > warn: passing casted pointer '&irq_status' to 'find_first_bit()' > > This code wouldn't work on a 64 bit big endian system because we would > read past the end of &irq_status. > > Fixes: 13ab8448d2c9 ("EDAC, altera: Add ECC Manager IRQ controller support") > Signed-off-by: Dan Carpenter > --- > Static analysis obviously and I don't know this subsystem at all. > Probably we're never going to run this on a 64 bit big endian system... > Feel free to ignore this if you want. > > drivers/edac/altera_edac.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c > index c2e693e34d43..bf024ec0116c 100644 > --- a/drivers/edac/altera_edac.c > +++ b/drivers/edac/altera_edac.c > @@ -1866,6 +1866,7 @@ static void altr_edac_a10_irq_handler(struct irq_desc *desc) > struct altr_arria10_edac *edac = irq_desc_get_handler_data(desc); > struct irq_chip *chip = irq_desc_get_chip(desc); > int irq = irq_desc_get_irq(desc); > + unsigned long bits; > > dberr = (irq == edac->db_irq) ? 1 : 0; > sm_offset = dberr ? A10_SYSMGR_ECC_INTSTAT_DERR_OFST : > @@ -1875,7 +1876,8 @@ static void altr_edac_a10_irq_handler(struct irq_desc *desc) > > regmap_read(edac->ecc_mgr_map, sm_offset, &irq_status); > > - for_each_set_bit(bit, (unsigned long *)&irq_status, 32) { > + bits = irq_status; > + for_each_set_bit(bit, &bits, 32) { > irq = irq_linear_revmap(edac->domain, dberr * 32 + bit); > if (irq) > generic_handle_irq(irq); > You are correct that we shouldn't use this on a 64 bit machine but this is a good fix. Thank you! Reviewed-by: Thor Thayer