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From: Juan Quintela <quintela@redhat.com>
In-Reply-To: <1271797792-24571-5-git-send-email-lcapitulino@redhat.com> (Luiz
	Capitulino's message of "Tue, 20 Apr 2010 18:09:34 -0300")
References: <1271797792-24571-1-git-send-email-lcapitulino@redhat.com>
	<1271797792-24571-5-git-send-email-lcapitulino@redhat.com>
Date: Tue, 20 Apr 2010 23:28:23 +0200
Message-ID: <m3mxwx3jbc.fsf@trasno.mitica>
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Subject: [Qemu-devel] Re: [PATCH 04/22] savevm: do_loadvm(): Always resume
	the VM
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To: Luiz Capitulino <lcapitulino@redhat.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com

Luiz Capitulino <lcapitulino@redhat.com> wrote:
> do_loadvm(), which implements the 'loadvm' Monitor command, pauses
> the emulation to load the saved VM, however it will only resume
> it if the loading succeeds.
>
> In other words, if the user issues 'loadvm' and it fails, the
> end result will be an error message and a paused VM.
>
> This seems an undesirable side effect to me because, most of the
> time, if a Monitor command fails the best thing we can do is to
> leave the VM as it were before the command was executed.
>
> FIXME: This will try to run a potentially corrupted image, the
>        solution is to split load_vmstate() in two and only keep
>        the VM paused if qemu_loadvm_state() fails.

Any of the other errors in loadvm also requires you to not load the
state.

> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

Nack.

This can cause disk corruption.  You tried to load a vm image, failed
the load somehow (notice the somehow) and you try to run it anyways.
That is a recipe for disaster.  If load_vmstate() fails -> you don't run.

Current code is a mess, but don't do things worse.

Later, Juan.