On Wed, Sep 10, 2008 at 07:18:43PM -0300, Glauber Costa wrote: > On Wed, Sep 10, 2008 at 05:58:42PM -0300, Marcelo Tosatti wrote: > > > > VMX initializes the TSC offset for each vcpu at different times, and > > also reinitializes it for vcpus other than 0 on APIC SIPI message. > > > > This bug causes the TSC's to appear unsynchronized in the guest, even if > > the host is good. > > > > Older Linux kernels don't handle the situation very well, so > > gettimeofday is likely to go backwards in time: > > > > http://www.mail-archive.com/kvm@vger.kernel.org/msg02955.html > > http://sourceforge.net/tracker/index.php?func=detail&aid=2025534&group_id=180599&atid=893831 > > > > Fix it by initializating the offset of each vcpu relative to vm creation > > time, and moving it from vmx_vcpu_reset to vmx_vcpu_setup, out of the > > APIC MP init path. > > How does it work if # vcpu > # pcpus? I remember that when I tried it, the > big biting dog were > cases in which all cpus tried to sync, but they naturally put the value "0" > in different points of time > (for obvious reasons), and would still appear unsynchronized to the guests.
Seems to work fine. All vcpus now put the value "0" relative to VM creation. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
