On 08/20/2014 02:10 AM, Michal Privoznik wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=1103245
An advice appeared there on the qemu-devel list [1]. When a domain is
suspended and then resumed guest kernel is not aware of this. So we've
introduced virDomainSetTime API that resets the time within guest
using qemu-ga. On the other hand, qemu itself is trying to make RTC
beat faster to catch the difference. But if we don't tell qemu that
guest's time was reset via the other method, both mechanisms are
applied resulting in again wrong guest time. In order to avoid summing
both corrections we need to tell qemu that it should not use the RTC
injection if the guest time is set via guest agent.
1:
http://www.mail-archive.com/qemu-devel@nongnu.org/msg236435.html
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
Notes:
diff to v2:
-introduced capability to test if qemu supports the monitor command
ACK.
+
+/**
+ * qemuMonitorRTCResetReinjection:
+ * @mon: Pointer to the monitor
+ *
+ * Issue rtc-reset-reinjection command.
+ * This should be used in cases where guest time is restored via
+ * guest agent so RTC injection is not needed (in fact it will
s/agent/agent,/
s/will/would/
+ * confuse guest's RTC).
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library
http://libvirt.org