From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f42.google.com (mail-qa0-f42.google.com [209.85.216.42]) by kanga.kvack.org (Postfix) with ESMTP id F21C56B0031 for ; Tue, 14 Jan 2014 10:26:41 -0500 (EST) Received: by mail-qa0-f42.google.com with SMTP id k4so5283215qaq.29 for ; Tue, 14 Jan 2014 07:26:41 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTP id t7si1042270qar.171.2014.01.14.07.26.40 for ; Tue, 14 Jan 2014 07:26:41 -0800 (PST) Date: Tue, 14 Jan 2014 10:26:27 -0500 From: Vivek Goyal Subject: Re: [PATCH] x86, acpi memory hotplug, add parameter to disable memory hotplug Message-ID: <20140114152627.GD3096@redhat.com> References: <1389650161-13292-1-git-send-email-prarit@redhat.com> <52D47999.5080905@redhat.com> <52D48EC4.5070400@jp.fujitsu.com> <1389663689.1792.268.camel@misato.fc.hp.com> <52D519EB.3040709@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52D519EB.3040709@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Prarit Bhargava Cc: Toshi Kani , Yasuaki Ishimatsu , KOSAKI Motohiro , LKML , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , the arch/x86 maintainers , Len Brown , "Rafael J. Wysocki" , Linn Crosetto , Pekka Enberg , Yinghai Lu , Andrew Morton , Tang Chen , Wen Congyang , Dave Young , linux-acpi@vger.kernel.org, "linux-mm@kvack.org" On Tue, Jan 14, 2014 at 06:05:15AM -0500, Prarit Bhargava wrote: [..] > >>> As mentioned, self-NAK. I have seen a system that I needed to specify > >>> memmap=exactmap & had hotplug memory. I will only keep the acpi_no_memhotplug > >>> option in the next version of the patch. > >> > >> > >> Your following first patch is simply and makes sense. > >> > >> http://marc.info/?l=linux-acpi&m=138922019607796&w=2 > >> > > > > In this option, it also requires changing kexec-tools to specify the new > > option for kdump. It won't be simpler. > > It will be simpler for the kernel and those of us who have to debug busted e820 > maps ;) > > Unfortunately I may not be able to give you the automatic disable. I did > contemplate adding a !is_kdump_kernel() to the ACPI memory hotplug init call, > but it seems like that is unacceptable as well. I think everybody agrees that there has to be a stand alone command line option to disable memory hotplug. Whether to tie it into memmap=exactmap and mem=X is the contentious bit. So I would suggest that just post a patch to disable memory hotplut using a command line and later more patches can go in if people strongly feel the need to tie it into memmap=exactmap. In the mean time, we will modify /etc/sysconfig/kdump to pass acpi_no_memhotplug so that user does not have to worry about passing this parameter and kexec-tools will not have to be modified either. Thanks Vivek -- 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