From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id CE6A96B028C for ; Mon, 26 Sep 2016 20:19:32 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id 21so419385336pfy.3 for ; Mon, 26 Sep 2016 17:19:32 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com. [148.163.156.1]) by mx.google.com with ESMTPS id d132si27519674pfg.218.2016.09.26.17.19.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Sep 2016 17:19:32 -0700 (PDT) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8R0IsqU112036 for ; Mon, 26 Sep 2016 20:19:31 -0400 Received: from e32.co.us.ibm.com (e32.co.us.ibm.com [32.97.110.150]) by mx0a-001b2d01.pphosted.com with ESMTP id 25q5ms62pr-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 26 Sep 2016 20:19:31 -0400 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 26 Sep 2016 18:19:30 -0600 Date: Mon, 26 Sep 2016 19:19:19 -0500 From: Reza Arbab Subject: Re: [PATCH v3 5/5] mm: enable CONFIG_MOVABLE_NODE on powerpc References: <1474828616-16608-1-git-send-email-arbab@linux.vnet.ibm.com> <1474828616-16608-6-git-send-email-arbab@linux.vnet.ibm.com> <1474924541.2857.258.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <1474924541.2857.258.camel@kernel.crashing.org> Message-Id: <20160927001919.sriijnhnu3c2jkck@arbab-laptop> Sender: owner-linux-mm@kvack.org List-ID: To: Benjamin Herrenschmidt Cc: Michael Ellerman , Paul Mackerras , Rob Herring , Frank Rowand , Jonathan Corbet , Andrew Morton , Bharata B Rao , Nathan Fontenot , Stewart Smith , Alistair Popple , Balbir Singh , "Aneesh Kumar K.V" , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, linux-mm@kvack.org On Tue, Sep 27, 2016 at 07:15:41AM +1000, Benjamin Herrenschmidt wrote: >What is that business with a command line argument ? Do that mean that >we'll need some magic command line argument to properly handle LPC memory >on CAPI devices or GPUs ? If yes that's bad ... kernel arguments should >be a last resort. Well, movable_node is just a boolean, meaning "allow nodes which contain only movable memory". It's _not_ like "movable_node=10,13-15,17", if that's what you were thinking. >We should have all the information we need from the device-tree. > >Note also that we shouldn't need to create those nodes at boot time, >we need to add the ability to create the whole thing at runtime, we may know >that there's an NPU with an LPC window in the system but we won't know if it's >used until it is and for CAPI we just simply don't know until some PCI device >gets turned into CAPI mode and starts claiming LPC memory... Yes, this is what is planned for, if I'm understanding you correctly. In the dt, the PCI device node has a phandle pointing to the memory node. The memory node describes the window into which we can hotplug at runtime. -- Reza Arbab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org