From patchwork Tue Dec 11 21:49:17 2012
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Subject: RTC: enable lost_tick_policy=slew as default
Date: Tue, 11 Dec 2012 11:49:17 -0000
From: Marcelo Tosatti <mtosatti@redhat.com>
X-Patchwork-Id: 205310
Message-Id: <20121211214916.GA3871@amt.cnet>
To: Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org

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(),
 };