Red Hat Bugzilla – Bug 1103245
libvirt reset rtc interrupt backlog after guest-set-time
Last modified: 2015-03-05 02:36:57 EST
libvirt should execute QMP's rtc_reset_reinjection command after executing guest-set-time guest agent command. This is necessary to avoid the problem described in the rtc_reset_reinjection patchset: http://www.mail-archive.com/qemu-devel@nongnu.org/msg236435.html
Patch proposed upstream: https://www.redhat.com/archives/libvir-list/2014-August/msg00576.html
Moving to POST: commit b606bbb416e264466a3f5af62a13163e432d0f49 Author: Michal Privoznik <mprivozn@redhat.com> AuthorDate: Wed Aug 13 14:28:24 2014 +0200 Commit: Michal Privoznik <mprivozn@redhat.com> CommitDate: Wed Aug 20 14:20:05 2014 +0200 qemu: Issue rtc-reset-reinjection command after guest-set-time 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@redhat.com> v1.2.7-184-gb606bbb
Try to set guest time with qemu-ga with libvirt-1.2.7-2, didn't see any event or logs about rtc_reset_reinjection in libvirt log, even set the log_level =1 in /etc/libvirt/libvirtd.log, so this bug reproduced. And after update the libvirt to the latest one libvirt-1.2.8-5.el7, i could catch the log that libvirt execute QMP's rtc_reset_reinjection command after executing guest-set-time guest agent command. so this bug can be markd verified. the following was the verify steps pkginfo libvirt-1.2.8-5.el7.x86_64 steps 1.Prepare a guest with qemu-ga installed 2.Setting logs for libvirt #cat /etc/libvirt/libvirtd.log log_level = 1 log_outputs="1:file:/var/log/libvirt/libvirtd.log" #service libvirtd restart 3.Set the time to the guest with the qemu-ga #virsh domtime rhel6 --time 12345 4.check the logs, could see the log that libvirt have executed QMP's rtc_reset_reinjection command after excuing guest-set-time guest agent command #cat /var/log/libvirt/libvirtd.log -- 2014-10-13 08:01:33.259+0000: 10545: debug : qemuAgentCommand:1104 : Send command '{"execute":"guest-set-time","arguments":{"time":90121345000000000}}' for write, seconds = -2 -- -- 2014-10-13 07:46:16.575+0000: 6314: debug : virJSONValueToString:1303 : result={"execute":"rtc-reset-reinjection","id":"libvirt-10"} 2014-10-13 07:46:16.575+0000: 6314: debug : qemuMonitorJSONCommandWithFd:286 : Send command '{"execute":"rtc-reset-reinjection","id":"libvirt-10"}' for write with FD -1 2014-10-13 07:46:16.575+0000: 6314: debug : qemuMonitorSend:976 : QEMU_MONITOR_SEND_MSG: mon=0x7f6f280079e0 msg={"execute":"rtc-reset-reinjection","id":"libvirt-10"}^M fd=-1 2014-10-13 07:46:16.575+0000: 6310: debug : qemuMonitorIOWrite:507 : QEMU_MONITOR_IO_WRITE: mon=0x7f6f280079e0 buf={"execute":"rtc-reset-reinjection","id":"libvirt-10"}^M len=55 ret=55 errno=11
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHSA-2015-0323.html