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Date: Wed, 2 Jan 2013 11:26:43 +0000
From: Andrew Cooper <andrew.cooper3@citrix.com>
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To: "Eric W. Biederman" <ebiederm@xmission.com>
CC: "x86@kernel.org" <x86@kernel.org>,
        "konrad.wilk@oracle.com" <konrad.wilk@oracle.com>,
        Daniel Kiper <daniel.kiper@oracle.com>,
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Subject: Re: [Xen-devel] [PATCH v3 00/11] xen: Initial kexec/kdump implementation
References: <1356574740-6806-1-git-send-email-daniel.kiper@oracle.com> <50DBC856.6030208@zytor.com> <791b4922-078f-4adc-b3f3-0651f2266147@email.android.com> <50DC58C4.3000307@citrix.com> <874nj7qsor.fsf@xmission.com>
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On 27/12/12 18:02, Eric W. Biederman wrote:
> Andrew Cooper<andrew.cooper3@citrix.com>  writes:
>
>> On 27/12/2012 07:53, Eric W. Biederman wrote:
>>> The syscall ABI still has the wrong semantics.
>>>
>>> Aka totally unmaintainable and umergeable.
>>>
>>> The concept of domU support is also strange.  What does domU support even mean, when the dom0 support is loading a kernel to pick up Xen when Xen falls over.
>> There are two requirements pulling at this patch series, but I agree
>> that we need to clarify them.
> It probably make sense to split them apart a little even.
>
>

Thinking about this split, there might be a way to simply it even more.

/sbin/kexec can load the "Xen" crash kernel itself by issuing hypercalls 
using /dev/xen/privcmd.  This would remove the need for the dom0 kernel 
to distinguish between loading a crash kernel for itself and loading a 
kernel for Xen.

Or is this just a silly idea complicating the matter?

~Andrew