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Subject: Re: [Xen-devel] [PATCH v3 00/11] xen: Initial kexec/kdump
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From: Ian Campbell <Ian.Campbell@citrix.com>
To: Andrew Cooper <andrew.cooper3@citrix.com>
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On Mon, 2013-01-07 at 10:46 +0000, Andrew Cooper wrote:

> Given that /sbin/kexec creates a binary blob in memory, surely the most 
> simple thing is to get it to suitably mlock() the region and give a list 
> of VAs to the hypervisor.

More than likely. The DOMID_KEXEC thing was just a radon musing ;-)

> This way, Xen can properly take care of what it does with information 
> and where.  For example, at the moment, allowing dom0 to choose where 
> gets overwritten in the Xen crash area is a recipe for disaster if a 
> crash occurs midway through loading/reloading the crash kernel.

That's true. I think there is a double buffering scheme in the current
thing and we should preserve that in any new implementation.

Ian.