From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:37419)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1TihvD-0003SX-Eg
	for qemu-devel@nongnu.org; Wed, 12 Dec 2012 03:44:13 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1Tihv7-0000vs-KT
	for qemu-devel@nongnu.org; Wed, 12 Dec 2012 03:44:07 -0500
Received: from mail-ea0-f173.google.com ([209.85.215.173]:41571)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1Tihv7-0000vo-Ca
	for qemu-devel@nongnu.org; Wed, 12 Dec 2012 03:44:01 -0500
Received: by mail-ea0-f173.google.com with SMTP id i13so131630eaa.4
	for <qemu-devel@nongnu.org>; Wed, 12 Dec 2012 00:44:00 -0800 (PST)
Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
Message-ID: <50C843CE.3030902@redhat.com>
Date: Wed, 12 Dec 2012 09:43:58 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
MIME-Version: 1.0
References: <20121211214916.GA3871@amt.cnet>
In-Reply-To: <20121211214916.GA3871@amt.cnet>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH] RTC: enable lost_tick_policy=slew as
	default
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org

Il 11/12/2012 22:49, Marcelo Tosatti ha scritto:
> 
> RTC interrupt reinjection has no known negative effect. Lack of 
> RTC interrupt reinjection, though, has negative effects: time drift
> for Windows guests which use it as a timer source. 
> 
> Based on that, enable lost_tick_policy=slew option as default.
> 
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> 
> diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c
> index c79fca7..c9e007d 100644
> --- a/hw/mc146818rtc.c
> +++ b/hw/mc146818rtc.c
> @@ -884,7 +884,7 @@ ISADevice *rtc_init(ISABus *bus, int base_year, qemu_irq intercept_irq)
>  static Property mc146818rtc_properties[] = {
>      DEFINE_PROP_INT32("base_year", RTCState, base_year, 1980),
>      DEFINE_PROP_LOSTTICKPOLICY("lost_tick_policy", RTCState,
> -                               lost_tick_policy, LOST_TICK_DISCARD),
> +                               lost_tick_policy, LOST_TICK_SLEW),
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> 
> 
> 

This needs versioning for old machine types, though.

Paolo