From mboxrd@z Thu Jan 1 00:00:00 1970 From: Baoquan He Subject: Re: [POC] Extend "movable_node" to "movable_node=nn@ss" and add the interface in /sys to show the value Date: Wed, 11 Oct 2017 16:42:15 +0800 Message-ID: <20171011084215.GB9142@x1> References: <20171011022827.GD13296@localhost.localdomain> <20171011075513.GA9142@x1> <20171011082319.GA15263@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx1.redhat.com ([209.132.183.28]:36920 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756608AbdJKImV (ORCPT ); Wed, 11 Oct 2017 04:42:21 -0400 Content-Disposition: inline In-Reply-To: <20171011082319.GA15263@localhost.localdomain> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Chao Fan Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-acpi@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, keescook@chromium.org, arnd@arndb.de, dyoung@redhat.com, dave.jiang@intel.com, lv.zheng@intel.com, rjw@rjwysocki.net, yasu.isimatu@gmail.com, caoj.fnst@cn.fujitsu.com, lizhijian@cn.fujitsu.com Hi dear Fan San, On 10/11/17 at 04:23pm, Chao Fan wrote: > On Wed, Oct 11, 2017 at 03:55:13PM +0800, Baoquan He wrote: > >Hi Fan San, > >> 1. Get and parse the srat table before kernel extracted, then mark the memory > >> region in movable node which should be avoided in kaslr. > >> I have send the patch: > >> https://www.spinics.net/lists/kernel/msg2595546.html > >> But the change is large and then here is the second method. > >> > >> 2. Extend the movable_node to movable_node=nn@ss, in which nn means > >> the size of memory in immovable node, and ss means the start position of > >> this memory region. > >> But it brings another question, it may be a little difficult for a normal > >> user to specify the nn and ss. Because it's hard for a user to know the value > >> of the memory in immovable node. > >> So I wonder if it's good to add a interface in /sys, like: > >> # cat /sys/device/system/memory/immovable_node > > > Hi Baoquan, > > Thanks for your reply, > > >You can post patch. By the way, can the existing > >/sys/devices/system/memory/memoryX/removable be used instead? > > I ever search the interfaces of /sys/devices/system/memory/, and noticed > this "removable", it does be able to help us judge it's removable or not. > But we should also get the information of the memory length and start position > by other interface. If there is a interface that show the nn and ss, we > can use them and change grub directly. > And there are more "memoryX" in one node. In my machine, I can see > memory0(linked to /sys/devices/system/memory/memory0) - memory7 in > /sys/devices/system/node/node0. And total memory38 for 4 nodes. I think > it's a little heavy to handle every memoryX. > But in SRAT table, one node has one or two memory regions. So I thinks > it's more straight and easy to use. How do you think about it? I am fine, I just mention it. Then please show your code envelopped in well formatted patch. Thanks Baoquan > > > >> nn@ss > >> nn@ss > >> ... > >> to show the two value. > >> When srat table is parsed in acpi_parse_memory_affinity, fill the value > >> and user can get and use them. > >> > >> If anyone has a better method, please let me know. > >> Any comments will be welcome. > >> > >> Thanks, > >> Chao Fan > >> > >> > > > > > >