From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932829AbaGPL2O (ORCPT ); Wed, 16 Jul 2014 07:28:14 -0400 Received: from service87.mimecast.com ([91.220.42.44]:51380 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932720AbaGPL2M convert rfc822-to-8bit (ORCPT ); Wed, 16 Jul 2014 07:28:12 -0400 Message-ID: <53C661CB.7040306@arm.com> Date: Wed, 16 Jul 2014 12:28:11 +0100 From: Sudeep Holla User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Alex Shi , "linux@arm.linux.org.uk" CC: Sudeep Holla , Pawel Moll , "nico@linaro.org" , "viresh.kumar@linaro.org" , "rafael.j.wysocki@intel.com" , "linux-kernel@vger.kernel.org" , "mark.brown@linaro.org" , "tixy@linaro.org" Subject: Re: [PATCH] vexpress/spc: fix a build warning on array bounds References: <1405509716-19591-1-git-send-email-alex.shi@linaro.org> In-Reply-To: <1405509716-19591-1-git-send-email-alex.shi@linaro.org> X-OriginalArrivalTime: 16 Jul 2014 11:28:09.0832 (UTC) FILETIME=[05921E80:01CFA0E9] X-MC-Unique: 114071612281007001 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Alex, On 16/07/14 12:21, Alex Shi wrote: > With ARCH_VEXPRESS_SPC option, kernel build has the following > warning: > > arch/arm/mach-vexpress/spc.c: In function ‘ve_spc_clk_init’: > arch/arm/mach-vexpress/spc.c:431:38: warning: array subscript is below array bounds [-Warray-bounds] > struct ve_spc_opp *opps = info->opps[cluster]; > ^ > since 'cluster' maybe '-1' in UP system. This patch does a active > checking to fix this issue. > Good catch, looks fine to me. Acked-by: Sudeep Holla > Signed-off-by: Alex Shi > --- > arch/arm/mach-vexpress/spc.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-vexpress/spc.c b/arch/arm/mach-vexpress/spc.c > index c26ef5b..4833544 100644 > --- a/arch/arm/mach-vexpress/spc.c > +++ b/arch/arm/mach-vexpress/spc.c > @@ -426,9 +426,15 @@ static int ve_spc_populate_opps(uint32_t cluster) > > static int ve_init_opp_table(struct device *cpu_dev) > { > - int cluster = topology_physical_package_id(cpu_dev->id); > - int idx, ret = 0, max_opp = info->num_opps[cluster]; > - struct ve_spc_opp *opps = info->opps[cluster]; > + int cluster; > + int idx, ret = 0, max_opp; > + struct ve_spc_opp *opps; > + > + cluster = topology_physical_package_id(cpu_dev->id); > + cluster = cluster < 0 ? 0 : cluster; > + > + max_opp = info->num_opps[cluster]; > + opps = info->opps[cluster]; > > for (idx = 0; idx < max_opp; idx++, opps++) { > ret = dev_pm_opp_add(cpu_dev, opps->freq * 1000, opps->u_volt); > @@ -537,6 +543,8 @@ static struct clk *ve_spc_clk_register(struct device *cpu_dev) > spc->hw.init = &init; > spc->cluster = topology_physical_package_id(cpu_dev->id); > > + spc->cluster = spc->cluster < 0 ? 0 : spc->cluster; > + > init.name = dev_name(cpu_dev); > init.ops = &clk_spc_ops; > init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE; >