Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752045AbdCAJUB (ORCPT ); Wed, 1 Mar 2017 04:20:01 -0500 Received: from mail-wr0-f196.google.com ([209.85.128.196]:35652 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751560AbdCAJT5 (ORCPT ); Wed, 1 Mar 2017 04:19:57 -0500 Date: Wed, 1 Mar 2017 10:10:07 +0100 From: Ingo Molnar To: Dou Liyang Cc: tglx@linutronix.de, hpa@zytor.com, bp@alien8.de, wanpeng.li@hotmail.com, nicstange@gmail.com, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/acpi: Fix a warning message in logical CPU IDs allocation Message-ID: <20170301091007.GB23669@gmail.com> References: <1488261052-25753-1-git-send-email-douly.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1488261052-25753-1-git-send-email-douly.fnst@cn.fujitsu.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2887 Lines: 78 * Dou Liyang wrote: > Current warning message regarded the "nr_cpu_ids - 1" as the limit > number of the CPUs. It may be confused us, for example: > we have two CPUs, nr_cpu_ids = 2, but the warning message may > indicate that we just have 1 CPU, which likes that: > Only 1 processors supported.Processor 2/0x2 and the rest > are ignored. > > Fix the warning message, replace "nr_cpu_ids - 1" with "nr_cpu_ids". > And the warning message can be like that: > APIC: NR_CPUS/possible_cpus limit of 2 reached. Processor 2/0x2 > and the rest are ignored. > > Signed-off-by: Dou Liyang The patch is correct, but the title is wrong (it's 'apic', not 'acpi'), plus the changelog is unreadable. Furthermore the changelog does not declare the changing of the return code to -EINVAL ... I fixed all that in the commit below, but please be more careful in the future. Thanks, Ingo =======================> >From bb3f0a52630c84807fca9bdd76ac2f5dcec82689 Mon Sep 17 00:00:00 2001 From: Dou Liyang Date: Tue, 28 Feb 2017 13:50:52 +0800 Subject: [PATCH] x86/apic: Fix a warning message in logical CPU IDs allocation The current warning message in allocate_logical_cpuid() is somewhat confusing: Only 1 processors supported.Processor 2/0x2 and the rest are ignored. As it might imply that there's only one CPU in the system - while what we ran into here is a kernel limitation. Fix the warning message to clarify all that: APIC: NR_CPUS/possible_cpus limit of 2 reached. Processor 2/0x2 and the rest are ignored. ( Also update the error return from -1 to -EINVAL, which is the more canonical return value. ) Signed-off-by: Dou Liyang Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bp@alien8.de Cc: nicstange@gmail.com Cc: wanpeng.li@hotmail.com Link: http://lkml.kernel.org/r/1488261052-25753-1-git-send-email-douly.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic/apic.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 4261b3282ad9..11088b86e5c7 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -2062,10 +2062,10 @@ static int allocate_logical_cpuid(int apicid) /* Allocate a new cpuid. */ if (nr_logical_cpuids >= nr_cpu_ids) { - WARN_ONCE(1, "Only %d processors supported." + WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %i reached. " "Processor %d/0x%x and the rest are ignored.\n", - nr_cpu_ids - 1, nr_logical_cpuids, apicid); - return -1; + nr_cpu_ids, nr_logical_cpuids, apicid); + return -EINVAL; } cpuid_to_apicid[nr_logical_cpuids] = apicid;