Red Hat Bugzilla – Bug 592033
race condition in pvclock wallclock calculation
Last modified: 2013-01-09 17:34:35 EST
+++ This bug was initially created as a clone of Bug #592021 +++
The hypervisor code for wallclock setting in pvclock is subject to race, since the version variable is static, and thus, shared among all guests.
This means that theoretically, one guest can mess up with the others view of version, causing it to be different among reads, which can lead to a livelock.
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux major release. Product Management has requested further
review of this request by Red Hat Engineering, for potential inclusion in a Red
Hat Enterprise Linux Major release. This request is not yet committed for
Patch(es) available on kernel-2.6.32-31.el6
Verify this bug with kernel-2.6.32-63.el6 as following:
1. sync time on host
ntpdate -b clock.redhat.com
2. Run 4 rhel6 guest on host with option
-no-kvm-pit-reinjection -rtc base=utc,clock=host,driftfix=slew
3.check time info on each guest
ntpdate -q clock.redhat.com
There is no huge time drift happens on each guest.
So I think this bug has been fixed. change status to verified.
Red Hat Enterprise Linux 6.0 is now available and should resolve
the problem described in this bug report. This report is therefore being closed
with a resolution of CURRENTRELEASE. You may reopen this bug report if the
solution does not work for you.