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Date: Tue, 18 Dec 2007 18:25:58 -0500
From: Vivek Goyal <vgoyal@redhat.com>
Subject: Re: [PATCH 0/8] kexec build system updates, to allow cross-kexec()ing
Message-ID: <20071218232558.GA14092@redhat.com>
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To: Jeremy Kerr <jk@ozlabs.org>
Cc: kexec@lists.infradead.org

On Tue, Dec 18, 2007 at 05:47:55PM +0900, Jeremy Kerr wrote:
> Hi all,
> 
> This series of patches is aimed at simplifying the kexec build system,
> mainly in order to make cross-compilation much easier.
> 
> As well as cross-compiling, this makes it possible to separate the
> 'host' architecture (ie, the arch of the kexec binary built), and the
> 'target' architecture (ie, the arch of the kernel that we're kexecing).
> We can specify these with the standard --host and --target arguments
> to configure.
> 

Hi Jermey,

I got a stupid question.

- What's the advantage of building a 32bit binary for powerpc64 bit
  platforms? IOW, why do you need to build 32bit purgatory? Can't we
  launch 32bit kernel from 64bit purgatory?

> This allows us to kexec a powerpc64 kernel from a powerpc userspace.
> x86{,_64} users might find this handy too, but I don't have hardware
> to test.

I think x86 it already happens. I think I can launch 64bit kernel from
a 32bit kexec.

Thanks
Vivek

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