Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932689AbbERTpu (ORCPT ); Mon, 18 May 2015 15:45:50 -0400 Received: from mail.skyhub.de ([78.46.96.112]:36627 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932114AbbERTpq (ORCPT ); Mon, 18 May 2015 15:45:46 -0400 Date: Mon, 18 May 2015 21:45:38 +0200 From: Borislav Petkov To: Prarit Bhargava Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Andy Lutomirski , Denys Vlasenko , Dave Hansen , Peter P Waskiewicz Jr , Igor Mammedov , Fenghua Yu Subject: Re: [PATCH] x86, cpuinfo fix cpu_data(0) x86_model_id field truncation Message-ID: <20150518194538.GD23618@pd.tnic> References: <1431973260-24617-1-git-send-email-prarit@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1431973260-24617-1-git-send-email-prarit@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1856 Lines: 48 On Mon, May 18, 2015 at 02:21:00PM -0400, Prarit Bhargava wrote: > When comparing 'model name' fields in /proc/cpuinfo it was noticed that > a simple test comparing the model name fields was failing. After some > simple investigation it was noticed that, in fact, the model name fields > are different for each processor. Processor 0's model name field had > white space removed, while the other processors did not. > > Another way of seeing this behaviour is to convert spaces into underscores > in the output of /proc/cpuinfo, > > [thetango@prarit ~]# grep "^model name" /proc/cpuinfo | uniq -c | sed 's/\ /_/g' > ______1_model_name :_AMD_Opteron(TM)_Processor_6272 > _____63_model_name :_AMD_Opteron(TM)_Processor_6272_________________ > > which shows two different model name fields even though they should be the > same. > > This occurs because the kernel calls strim() on cpu 0's x86_model_id field I'd actually prefer this much simpler patch: --- diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index e7d8c7608471..d215e9b26567 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -67,7 +67,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) c->x86_vendor_id[0] ? c->x86_vendor_id : "unknown", c->x86, c->x86_model, - c->x86_model_id[0] ? c->x86_model_id : "unknown"); + c->x86_model_id[0] ? strim(c->x86_model_id) : "unknown"); if (c->x86_mask || c->cpuid_level >= 0) seq_printf(m, "stepping\t: %d\n", c->x86_mask); --- -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- 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/