From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Message-ID: <18476.1203.459931.530585@cargo.ozlabs.ibm.com> Date: Thu, 15 May 2008 19:38:59 +1000 From: Paul Mackerras To: benh@kernel.crashing.org Subject: Re: PS3: Fix memory hotplug In-Reply-To: <1210834125.8297.80.camel@pasglop> References: <4829C07A.4040407@am.sony.com> <1210834125.8297.80.camel@pasglop> Cc: "linuxppc-dev@ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Benjamin Herrenschmidt writes: > When you do an lmb_add you should probably also do an lmb_analyze to > update the total memory count etc... > > That leads to some interesting issues such as the LMB stuff wasn't > really meant to be dynamically modified after boot, and thus the kernel > has no locks in there. That can be an issue... > > Paul, any thoughts here ? Should we add a lock ? That would mean being > careful as the LMB stuff can be called very early, and spinlock wants > things like PACA and possibly lockdep to be around.. Either that, or we give in and use iomem_resource to track where system RAM is, as well as the other things in the physical address space, like other architectures do... Paul.