From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:37956) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QWRIJ-0005YP-GV for qemu-devel@nongnu.org; Tue, 14 Jun 2011 06:56:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QWRIF-0002IF-4M for qemu-devel@nongnu.org; Tue, 14 Jun 2011 06:56:27 -0400 Received: from thoth.sbs.de ([192.35.17.2]:25118) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QWRIE-0002F9-HA for qemu-devel@nongnu.org; Tue, 14 Jun 2011 06:56:22 -0400 Message-ID: <4DF73E52.8090004@siemens.com> Date: Tue, 14 Jun 2011 12:56:18 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <4DF32FC6.3040607@web.de> <4DF4F3CB.1070408@redhat.com> <4DF6FD6D.6020109@web.de> <4DF73CFF.3070403@redhat.com> In-Reply-To: <4DF73CFF.3070403@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH] Reset system before loadvm List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Avi Kivity Cc: qemu-devel , Luiz Capitulino On 2011-06-14 12:50, Avi Kivity wrote: > On 06/14/2011 09:19 AM, Jan Kiszka wrote: >> On 2011-06-12 19:13, Avi Kivity wrote: >> > On 06/11/2011 12:05 PM, Jan Kiszka wrote: >> >> From: Jan Kiszka >> >> >> >> In case we load the vmstate during incoming migration, we start >> from a >> >> clean, default machine state as we went through system reset >> before. But >> >> if we load from a snapshot, the machine can be in any state. That can >> >> cause troubles if loading an older image which does not carry all >> state >> >> information the executing QEMU requires. Almost no device takes >> care of >> >> this scenario. >> >> >> >> However, fixing this is trivial. We just need to issue a system reset >> >> during loadvm as well. >> > >> >> + qemu_system_reset(); >> >> ret = qemu_loadvm_state(f); >> >> >> >> qemu_fclose(f); >> > >> > Should we suppress the reset event sent out on the monitor? After >> all, >> > it's the result of an internal implementation choice, not something >> the >> > user or the guest did. >> >> We already issue this pattern during -loadvm or -incoming - or is the >> monitor not yet connected at this point? > > I believe it is not. But regardless, we shouldn't add more incorrect > behaviour. It depends on how the reset event is defined in QMP. As I see it, there is nothing stated about reset reasons or sources. So emitting information about the actually happening reset can't be incorrect. Just like emitting the information about the VM stop/start around loadvm. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux