From mboxrd@z Thu Jan  1 00:00:00 1970
From: Toshi Kani <toshi.kani@hp.com>
Subject: Re: [PATCH] x86, acpi memory hotplug, add parameter to disable
 memory hotplug
Date: Tue, 14 Jan 2014 08:31:22 -0700
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To: Vivek Goyal <vgoyal@redhat.com>
Cc: Prarit Bhargava <prarit@redhat.com>, Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>, KOSAKI Motohiro <kosaki.motohiro@gmail.com>, LKML <linux-kernel@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, the arch/x86 maintainers <x86@kernel.org>, Len Brown <lenb@kernel.org>, "Rafael J. Wysocki" <rjw@rjwysocki.net>, Linn Crosetto <linn@hp.com>, Pekka Enberg <penberg@kernel.org>, Yinghai Lu <yinghai@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, Tang Chen <tangchen@cn.fujitsu.com>, Wen Congyang <wency@cn.fujitsu.com>, Dave Young <dyoung@redhat.com>, linux-acpi@vger.kernel.org, "linux-mm@kvack.org" <linux-mm@kvack.org>

On Tue, 2014-01-14 at 10:26 -0500, Vivek Goyal wrote:
> 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.

Fine by me.  Thanks for modifying /etc/sysconfig/kdump file. 
-Toshi