From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman)
Subject: Re: [PATCH 0/2] kvm: disable virtualization on kdump
Date: Mon, 27 Oct 2008 08:05:50 -0700
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Cc: Andrew Morton <akpm-3NddpPZAyC0@public.gmane.org>, Eduardo Habkost <ehabkost-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
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	Vivek Goyal <vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: Avi Kivity <avi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
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In-Reply-To: <49058645.9010005-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> (Avi Kivity's message of "Mon, 27
	Oct 2008 11:13:41 +0200")
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Avi Kivity <avi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> writes:

> There's no way to query whether vmx is enabled or disabled, AFAICT.  So we have
> to execute vmxoff and ignore possible #UDs.
>
> If we trust the exception handlers, there's no problem.  Otherwise we need to
> replace the current #UD handler with an iret (perhaps switching temporarily to
> another IDT).

Ugh.  We already change the IDT on that code path so that
may be a way to go.

> The general kexec path also wants this fixed.

It looks like someone hooked the reboot notifier which should
be called on the normal kexec path.

Eric