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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 372FCC2BA83 for ; Thu, 13 Feb 2020 14:33:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 156B320873 for ; Thu, 13 Feb 2020 14:33:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727455AbgBMOd2 (ORCPT ); Thu, 13 Feb 2020 09:33:28 -0500 Received: from lhrrgout.huawei.com ([185.176.76.210]:2423 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727511AbgBMOd2 (ORCPT ); Thu, 13 Feb 2020 09:33:28 -0500 Received: from lhreml704-cah.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id 839855F30B63786EFC09; Thu, 13 Feb 2020 14:33:26 +0000 (GMT) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by lhreml704-cah.china.huawei.com (10.201.108.45) with Microsoft SMTP Server (TLS) id 14.3.408.0; Thu, 13 Feb 2020 14:33:26 +0000 Received: from [127.0.0.1] (10.202.226.45) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Thu, 13 Feb 2020 14:33:26 +0000 Subject: Re: About PPTT find_acpi_cpu_topology_package() To: Sudeep Holla CC: Jeremy Linton , "Guohanjun (Hanjun Guo)" , ACPI Devel Maling List , "liuqi (BA)" , wanghuiqiang , "wangxiongfeng (C)" References: <7a888a84-d4c5-2b49-05f3-29876d49cae6@huawei.com> <20200212115945.GA36981@bogus> <20200212135551.GB36981@bogus> <1a04ddf8-4903-2986-a94e-c070dc2c2160@huawei.com> <3c15a54a-18ac-265e-c16c-272577b9dead@arm.com> <20200213140006.GB31787@bogus> From: John Garry Message-ID: <76c2c4fa-3466-171b-3538-9a7374f4baae@huawei.com> Date: Thu, 13 Feb 2020 14:33:25 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: <20200213140006.GB31787@bogus> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.226.45] X-ClientProxiedBy: lhreml720-chm.china.huawei.com (10.201.108.71) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On 13/02/2020 14:00, Sudeep Holla wrote: > On Thu, Feb 13, 2020 at 11:52:09AM +0000, John Garry wrote: > > [...] > Hi Sudeep, >> >> As for when it's not set, it's unclear. My understanding is that the ACPI >> processor id should still be used as the non-leaf node identifier, but it >> would not match a UID for a processor container (as it may not exist). >> > > I can't infer anything that matches your understanding from the spec in > this regard. If it's not set, then it is left to OSPM. > ACPI Processor ID valid just means that there is an associated processor container entry which has a UID which matches the ACPI Processor ID for this node. I can't see anything to say that if the ACPI Processor ID valid flag is unset then the ACPI processor ID itself is not still a valid identifier. As such, it's implied that it is still valid. But the spec should be clarified here. >> The kernel does have behave according to this. >> > > According to what in the specification ? That's just based on my interpretation, above. That being, the ACPI Processor ID is always valid, independent of whether ACPI Processor ID valid flag is set. > >> So how I am misinterpreting this? >> > > May be you are not, it is just ambiguous in the spec, worth checking and > fixing if it is an issue. Absolutely agree on all of this. > I reiterate we don't want to generate anything > in the OS for this purpose. I'm ok with that. Cheers, John