From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758581Ab3LFO5O (ORCPT ); Fri, 6 Dec 2013 09:57:14 -0500 Received: from g5t0006.atlanta.hp.com ([15.192.0.43]:17167 "EHLO g5t0006.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756540Ab3LFO5M (ORCPT ); Fri, 6 Dec 2013 09:57:12 -0500 Message-ID: <1386341536.1791.283.camel@misato.fc.hp.com> Subject: Re: [PATCH] mm, x86: Skip NUMA_NO_NODE while parsing SLIT From: Toshi Kani To: Yasuaki Ishimatsu Cc: akpm@linux-foundation.org, mingo@kernel.org, hpa@zytor.com, tglx@linutronix.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org Date: Fri, 06 Dec 2013 07:52:16 -0700 In-Reply-To: <52A17B83.8060601@jp.fujitsu.com> References: <1386191348-4696-1-git-send-email-toshi.kani@hp.com> <52A054A0.6060108@jp.fujitsu.com> <1386256309.1791.253.camel@misato.fc.hp.com> <52A17B83.8060601@jp.fujitsu.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.8.5 (3.8.5-2.fc19) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2013-12-06 at 16:23 +0900, Yasuaki Ishimatsu wrote: > (2013/12/06 0:11), Toshi Kani wrote: > > On Thu, 2013-12-05 at 19:25 +0900, Yasuaki Ishimatsu wrote: > >> (2013/12/05 6:09), Toshi Kani wrote: > >>> When ACPI SLIT table has an I/O locality (i.e. a locality unique > >>> to an I/O device), numa_set_distance() emits the warning message > >>> below. > >>> > >>> NUMA: Warning: node ids are out of bound, from=-1 to=-1 distance=10 > >>> > >>> acpi_numa_slit_init() calls numa_set_distance() with pxm_to_node(), > >>> which assumes that all localities have been parsed with SRAT previously. > >>> SRAT does not list I/O localities, where as SLIT lists all localities > >> > >>> including I/Os. Hence, pxm_to_node() returns NUMA_NO_NODE (-1) for > >>> an I/O locality. I/O localities are not supported and are ignored > >>> today, but emitting such warning message leads unnecessary confusion. > >> > >> In this case, the warning message should not be shown. But if SLIT table > >> is really broken, the message should be shown. Your patch seems to not care > >> for second case. > > > > In the second case, I assume you are worrying about the case of SLIT > > table with bad locality numbers. Since SLIT is a matrix of the number > > of localities, it is only possible by making the table bigger than > > necessary. Such excessive localities are safe to ignore (as they are > > ignored today) and regular users have nothing to concern about them. > > The warning message in this case may be helpful for platform vendors to > > test their firmware, but they have plenty of other methods to verify > > their SLIT table. > > I understood it. So, > > Reviewed-by : Yasuaki Ishimatsu Great. Thanks Yasuaki! -Toshi