Re: [dpdk-dev] [PATCH v3 0/2] IOPL related fixes

[David Marchand <david.marchand@redhat.com>]

On Sun, Nov 25, 2018 at 11:42 AM Thomas Monjalon <thomas@monjalon.net>
wrote:

> 23/11/2018 23:29, Thomas Monjalon:
> > 23/11/2018 21:07, Kevin Traynor:
> > > On 11/23/2018 04:25 PM, Maxime Coquelin wrote:
> > > > On 11/23/18 4:53 PM, Ilya Maximets wrote:
> > > >> On 23.11.2018 18:41, Maxime Coquelin wrote:
> > > >>> On 11/23/18 4:39 PM, Ilya Maximets wrote:
> > > >>>> Patches primary targeted to fix OVS unit test failures with
> > > >>>> DPDK 18.11 due to following error:
> > > >>>>       'IOPL call failed - cannot use virtio PMD'.
> > > >>>
> > > >>> You mention v18.11, do you mean this is a regression?
> > > >>
> > > >> Kind of. But not really a bug. It's just a message that shows up
> > > >> every time you starting the app as a non-root user.
> > > >>
> > > >> The message itself was introduced long time ago, but it wasn't
> > > >> printed for unclear reasons. It's probably some change in logging
> > > >> subsystem uncovered it.
> > > >>
> > > >> I just checked and found that message appears starting from v18.02.
> > > >> But OVS stuck with 17.11 LTS where this message exists, but not
> > > >> printed for some reason. That's why this wasn't an issue previously.
> > > >
> > > > Thanks for the clarification.
> > > > In that case, we may want it in v18.11 LTS, but I think it can wait
> or
> > > > v18.11.1.
> > >
> > > It would be better if it can be in 18.11. Upstream OVS will point at a
> > > release tarball, and at present an 18.11.1 release is not due until
> > > mid-January. If it's too late for 18.11, alternatively we could do an
> > > earlier 18.11.1 release.
> >
> > I won't take any risk at this stage.
> > The memory of the headaches we had in the past with iopl is too much
> strong.
> > The real change of this patch is to register the PMD even without
> successful iopl.
> > I would like to be sure it won't cause any regression.
>
> After more thinking, I decide to take the risk.
> Take it as a gift to OVS :-)
>

Just for the record, this log is visible by default since 18.02 with commit:
0062818856c3 ("net/virtio: implement dynamic logging")

So probably worth backporting in 18.08 at least.

-- 
David Marchand