> > > > is it (new userland + old kernel) expected to work?  i don't think so.
> > > 
> > > In this case it's not "new userland", it's a software from a newer pkgsrc
> > > built on an older system.
> > 
> > sorry, i don't understand your point.
> > xentools is an userland application.
> > any userland applications which rely on something new in kernel are not
> > expected to work with older kernel.
> > whether it's in basesrc or not is not related.
> 
> It is, because pkgsrc softwares are expected to build and run on older
> systems.

do you mean, we need to keep xentools in pkgsrc to use old version of
IOCTL_PRIVCMD_INITDOMAIN_EVTCHN?

> > > The upgrade path for the /kern mmap issue is:
> > > update pkgsrc and rebuild xentools20
> > > update kernel
> > > reboot
> > > if something goes wrong with the new kenrel you can still go back to the
> > > old one.
> > 
> > you can go back to the old xentools, can't you?
> 
> Once you have updated pkgsrc and installed the new tools, it's not as easy
> as rebooting on an older kernel.

i think you can boot domain0 with old kernel and install old xentools.

YAMAMOTO Takashi