Re: [patch 00/11] x86/vdso: Cleanups, simmplifications and CLOCK_TAI support

From: Thomas Gleixner
Date: Wed Oct 03 2018 - 11:10:19 EST


On Wed, 3 Oct 2018, Andy Lutomirski wrote:
> > On Oct 3, 2018, at 5:01 AM, Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:
> > Not all Hyper-V hosts support reenlightenment notifications (and, if I'm
> > not mistaken, you need to enable nesting for the VM to get the feature -
> > and most VMs don't have this) so I think we'll have to keep Hyper-V
> > vclock for the time being.
> >
> But this does suggest that the correct way to pass a clock through to an
> L2 guest where L0 is HV is to make L1 use the âtscâ clock and L2 use
> kvmclock (or something newer and better). This would require adding
> support for atomic frequency changes all the way through the timekeeping
> and arch code.
>
> John, tglx, would that be okay or crazy?

Not sure what you mean. I think I lost you somewhere on the way.

Thanks,

tglx