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Date: Fri, 22 Feb 2013 11:54:52 +0000
From: David Vrabel <david.vrabel@citrix.com>
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Subject: Re: [Xen-devel] [PATCH 5/8] kexec: extend hypercall with improved
 load/unload ops
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To: Jan Beulich <JBeulich@suse.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>, "kexec@lists.infradead.org" <kexec@lists.infradead.org>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>

On 22/02/13 08:42, Jan Beulich wrote:
>>>> On 21.02.13 at 18:48, David Vrabel <david.vrabel@citrix.com> wrote:
>> Crash images are copied directly into the crash region on load.
>> Default images are copied into Xen heap pages and a list of source and
>> destination machine addresses is created.  This is list is used in
>> kexec_reloc() to relocate the image to its destination.
> 
> Did you carefully consider the implications of using Xen heap pages
> here as opposed to domain heap ones? On huge systems, this may
> prevent kexec from working, as you're not just trying to allocate a
> handful of pages. IOW, is the less complex code really worth the
> increased likelihood of a failure here?

I wouldn't say carefully considered... I thought about using dom heap
briefly and took the lazy route.

I take your point though and will change it to use the dom heap.  Is
there a way to verify that all the map/unmaps are correctly done and it
isn't just working by chance?  Some sort of debug option?

David

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