linux-kernel - Re: [PATCH v13 1/8] save/load cpu runstate

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 05 Mar 2013 09:24:24 +0100
From:	Paolo Bonzini <pbonzini@...hat.com>
To:	Hu Tao <hutao@...fujitsu.com>
CC:	kvm list <kvm@...r.kernel.org>, qemu-devel <qemu-devel@...gnu.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"Daniel P. Berrange" <berrange@...hat.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Jan Kiszka <jan.kiszka@...mens.com>,
	Gleb Natapov <gleb@...hat.com>,
	Blue Swirl <blauwirbel@...il.com>,
	Eric Blake <eblake@...hat.com>,
	Andrew Jones <drjones@...hat.com>,
	Marcelo Tosatti <mtosatti@...hat.com>,
	Sasha Levin <levinsasha928@...il.com>,
	Luiz Capitulino <lcapitulino@...hat.com>,
	Anthony Liguori <aliguori@...ibm.com>,
	Markus Armbruster <armbru@...hat.com>,
	Stefan Hajnoczi <stefanha@...hat.com>,
	Juan Quintela <quintela@...hat.com>,
	Orit Wasserman <owasserm@...hat.com>,
	Kevin Wolf <kwolf@...hat.com>,
	Wen Congyang <wency@...fujitsu.com>,
	"Michael S. Tsirkin" <mst@...hat.com>,
	Alexander Graf <agraf@...e.de>,
	Alex Williamson <alex.williamson@...hat.com>,
	Peter Maydell <peter.maydell@...aro.org>
Subject: Re: [PATCH v13 1/8] save/load cpu runstate

Il 05/03/2013 03:33, Hu Tao ha scritto:
> On Mon, Mar 04, 2013 at 10:30:48AM +0100, Paolo Bonzini wrote:
>> Il 28/02/2013 13:13, Hu Tao ha scritto:
>>> This patch enables preservation of cpu runstate during save/load vm.
>>> So when a vm is restored from snapshot, the cpu runstate is restored,
>>> too.
>>
>> I don't think this feature is worth breaking backwards migration
>> compatibility.  It is usually handled at a higher-level (management,
>> like libvirt).
> 
> If guest panic happens during migration, runstate will still be running
> on destination host without this patch. But, it does be a problem to break
> backwards migration compatibility.

Yes, but the source management (libvirt for example) will have the
occasion to observe the change and cancel the migration or forward the
information on the wire.  There are already similar reasons why libvirt
always starts guests with -S.

Paolo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/