Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030298AbWHDDAN (ORCPT ); Thu, 3 Aug 2006 23:00:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030301AbWHDDAN (ORCPT ); Thu, 3 Aug 2006 23:00:13 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:42164 "EHLO e33.co.us.ibm.com") by vger.kernel.org with ESMTP id S1030298AbWHDDAL (ORCPT ); Thu, 3 Aug 2006 23:00:11 -0400 Subject: Re: [PATCH] memory hotadd fixes [4/5] avoid check in acpi From: keith mannthey Reply-To: kmannth@us.ibm.com To: KAMEZAWA Hiroyuki Cc: lkml , lhms-devel , y-goto@jp.fujitsu.com, andrew In-Reply-To: <20060804111550.ab30fc15.kamezawa.hiroyu@jp.fujitsu.com> References: <20060803123604.0f909208.kamezawa.hiroyu@jp.fujitsu.com> <1154650396.5925.49.camel@keithlap> <20060804094443.c6f09de6.kamezawa.hiroyu@jp.fujitsu.com> <1154656472.5925.71.camel@keithlap> <20060804111550.ab30fc15.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain Organization: Linux Technology Center IBM Date: Thu, 03 Aug 2006 20:00:08 -0700 Message-Id: <1154660408.5925.79.camel@keithlap> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-4) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2447 Lines: 66 On Fri, 2006-08-04 at 11:15 +0900, KAMEZAWA Hiroyuki wrote: > On Thu, 03 Aug 2006 18:54:32 -0700 > keith mannthey wrote: > > > > Hmm..Okay. I'll try some check patch today. please review it. > > > Maybe moving ioresouce collision check in early stage of add_memory() is good ? > > Yea. I am working a a full patch set for but my sparsemem and reserve > > add-based paths. It creates a valid_memory_add_range call at the start > > of add_memory. I should be posting the set in the next few hours. > > > Ah..ok. but I wrote my own patch...and testing it now.. Sure that is fine. > > > > Note: > > > I remove pfn_valid() here because pfn_valid() just says section exists or > > > not. When adding seveal small memory chunks in one section, Only the first > > > small chunk can be added. > > Hmm... I thought memory add areas needed to be section aligned for the arch? > > > There are requests for memory-hot-add should allow to hot-add not-aligned memory. > Then, I wrote ioresouce collision check patch (before..but had bug..) > With ioresouce collistion check, alignments are not required at *add*. > (onlining is just for *offlined section*, now) > > > What protecting is there for calling add_memory on an already present > > memory range? > > > For example, considering ia64, which has 1Gbytes section... Maybe 1gb sections is too large? > hot add following region. > == > (A) 0xc0000000 - 0xd7ffffff (section 3) > (B) 0xe0000000 - 0xffffffff (section 3) > == > (A) and (B) will go to the same section, but there is a memory hole between > (A) and (B). Considering memory (B) appears after (A) in DSDT. > > After add_memory() against (A) is called, section 3 is ready. > Then, pfn_valid(0xe0000000) and pfn_valid(0xffffffff) returns true because > they are in section 3. > So, checking pfn_valid() for (B) will returns true and memory (B) cannot be > added. ioresouce collision check will help this situation. With iommus out there throwing aliment all off way the flexability is good. My question is this. Assuming 0-0xbfffffff is present. What keeps 0xa0000000 to 0xa1000000 from being re-onlined by a bad call to add_memory? Thanks, Keith - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/