Re: [PATCH v5 0/3] Add support for the RAPL MSRs series

[Paolo Bonzini <pbonzini@redhat.com>]

On Wed, Apr 17, 2024 at 7:58 PM Daniel P. Berrangé <berrange@redhat.com> wrote:
> > > However, one question remains unanswered pointing the issue with the
> > > location of "/var/local/run/qemu-vmsr-helper.sock", created by
> > > compute_default_paths(). QEMU is not allowed to reach the socket here.
> >
> > If I understand correctly the question, that is expected. This is a
> > privileged functionality and therefore it requires manual intervention
> > to change the owner of the socket and allow QEMU to access it.
>
> In the systemd case, it will set the owner and mode, but in the
> non-system case, I wonder if it worth making this helper program
> have "--socket-owner" and "--socket-mode" args, so it can create
> the socket with the right mode/owner immediately, rather than
> expecting the admin to manuall chmod+chown after start the
> helper

I think a better idea would be to contribute them to
systemd-socket-activate, and just launch the helper that way. It's
mostly a testing tool, but tbh if you're not using systemd you're on
your own. If you write an init script for example, that would be the
place where you put the chmod/chown.

Paolo