On Tue, 21 Oct 2014, Thomas Shao wrote: > > I still do not have a consistent argument from you WHY you need to abuse > > do_adjtimex() to do that host - guest synchronization in the first place. > > > > I need a function to gradually slew guest time. do_adjtimex() provides all the > functionality. Also I could not find any other exposed func to do this. I'd like to > hear any feedback from you for this. As Richard and others told you already, there are various options: 1) Use NTP on that private network, which does not involve any kernel changes at all. Your argument, that this is hard for IT-Admins to set up is just ridiculous. If an IT-Admin is not able to set that up, then he should better stay away from setting up a guest in the first place, really. 2) As pointed out already by others PPS/PTP might be a proper solution for this. All it takes is a pair of timestamps (host/guest) injected into the proper subsystem and a controlling daemon on the guest side. That would also avoid the problem of running NTPd and your kernel side poor mans NTPd at the same time. That pseudo NTP thing is just hilarious, really. You take the host time stamp in timesync_onchannelcallback() and schedule work. From the work queue you correlate the host time stamp to the current time of the guest. So you correlate time stamps which can be an arbitrary time apart. Brilliant solution that, really. Thanks, tglx _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
