Re: [kvm-devel] [PATCH 0/4] paravirt clock patches

[Marcelo T. <mto...@re...>]

On Wed, May 07, 2008 at 08:45:12PM +0200, Gerd Hoffmann wrote:
> Ok folks, here is the band aid fix for testing from the odd bugs
> department.  Goes on top of the four patches of this series.  A real,
> clean solution is TBD.  Tomorrow I hope (some urgent private problems
> are in the queue too ...).
> 
> Problem is the per-cpu area for cpu 0 has two locations in memory, one
> before and one after pda initialization.  kvmclock registers the first
> due to being initialized quite early, and the paravirt clock for cpu 0
> stops seeing updates once the pda setup is done.  Which makes the TSC
> effectively the base for timekeeping (instead of using the TSC for
> millisecond delta adjustments only).  Secondary CPUs work as intended.
> 
> This obviously screws up timekeeping on SMP guests, especially on hosts
> with unstable TSC.
> 
> happy testing,

Gerd,

SMP guests can boot and seem stable. Thanks!