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Date: Wed, 21 Aug 2013 16:37:56 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] vl: allow "cont" from panicked state
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org, pkrempa@redhat.com, marcel.a@redhat.com, libvir-list@redhat.com, hutao@cn.fujitsu.com, qemu-stable@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>, rhod@redhat.com, kraxel@redhat.com, anthony@codemonkey.ws, Laszlo Ersek <lersek@redhat.com>, afaerber@suse.de

Il 21/08/2013 16:30, Michael S. Tsirkin ha scritto:
>> I think the same reasoning went behind the PANICKED state, and for most
>> cases it's going to be disastrous to put the guest to run again,
> 
> Why will it? It will most likely just call halt a bit later.

I agree.

>> but I can understand that this is up user/mngt to decide this, not QEMU.
> 
> I don't have a problem with this patch as such, so
> 
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> 
> though I'm still not really sure why do we
> want to block guest immediately on panic.
> Why not let it call halt a bit later?

To make sure the panic is detected, and action taken, in the host even
if management has crashed at the time.  For example, even if you have
reboot-on-panic active, management has time to take a core dump of the
paused guest _before_ the reboot.

Paolo