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From: Juan Quintela <quintela@redhat.com>
In-Reply-To: <1400095810-27684-18-git-send-email-ehabkost@redhat.com> (Eduardo
	Habkost's message of "Wed, 14 May 2014 16:30:09 -0300")
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	<1400095810-27684-18-git-send-email-ehabkost@redhat.com>
Date: Thu, 15 May 2014 14:17:11 +0200
Message-ID: <87y4y38ce0.fsf@elfo.mitica>
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Subject: Re: [Qemu-devel] [PATCH RESEND v4 17/18] target-i386: block
	migration and savevm if invariant tsc is exposed
Reply-To: quintela@redhat.com
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To: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Andreas =?utf-8?Q?F=C3=A4rber?= <afaerber@suse.de>

Eduardo Habkost <ehabkost@redhat.com> wrote:
> From: Marcelo Tosatti <mtosatti@redhat.com>
>
> Invariant TSC documentation mentions that "invariant TSC will run at a
> constant rate in all ACPI P-, C-. and T-states".
>
> This is not the case if migration to a host with different TSC frequency
> is allowed, or if savevm is performed. So block migration/savevm.
>
> Cc: Juan Quintela <quintela@redhat.com>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

Reviewed-by: Juan Quintela <quintela@redhat.com>

I don't have a better suggestion.  Really we could allow migration to
identical machines, but I assume that there is not a way to read the tsc
frequency?
(Althought reading the model name/numbers could be enough?)

I.e. Add a subsection that includes the cpu model name, or whatever we
can have to identify the host cpu?

Later, Juan.