Re: [Intel-wired-lan] [PATCH 2/3] e1000e: Make mei_me active when e1000e is in use

[Sasha Neftin]

On 7/14/2021 12:52, Kai-Heng Feng wrote:
> On Wed, Jul 14, 2021 at 5:06 PM Ruinskiy, Dima <dima.ruinskiy@xxxxxxxxx> wrote:
> > On 14/07/2021 9:28, Kai-Heng Feng wrote:
> > > > I do not know how MEI driver affect 1Gbe driver - so, I would suggest to
> > > > involve our CSME engineer (alexander.usyskin@xxxxxxxxx) and try to
> > > > investigate this problem.
> > > > Does this problem observed on Dell systems? As I heard no reproduction
> > > > on Intel's RVP platform.
> > > > Another question: does disable mei_me runpm solve your problem?
> > >
> > > Yes, disabling runpm on mei_me can workaround the issue, and that's
> > > essentially what this patch does by adding DL_FLAG_PM_RUNTIME |
> > > DL_FLAG_RPM_ACTIVE flag.
> > >
> > > Kai-Heng
> > Hi, Kai-Heng,
> >
> > If the goal of the patch is to essentially disable runpm on mei_me, then
> > why is the patch touching code in the e1000e driver?
>
> We can put the workaround in e1000e, mei_me or as PCI quirk.
> But since the bug itself manifests in e1000e, I think it's more
> appropriate to put it here.
>
> To be more specific, it doesn't disable runtime suspend on mei_me, it
> makes mei_me the power supplier of e1000e.
> So when e1000e can be runtime suspended (i.e. no link partner), mei_me
> can also get runtime suspended too.
> > I agree with Sasha Neftin; it seems like the wrong location, and the
> > wrong way to do it, even if it currently works. We need to understand
> > what causes runpm of mei_me to adversely affect LAN Rx, and for this we
> > need the involvement of mei_me owners.
>
> I think it's the right location, however I totally agree with your
> other arguments.
> There are many users already affected by this bug, so if a proper fix
> isn't available for now, the temporary workaround can help here.
Hello Kai-Heng,
The temporary workaround without root cause is vague. Please, let's work 
with the manageability FW engineer (alexander.usyskin@xxxxxxxxx) and 
understand the root cause.
Also, here is interfere with runpm flow of CSME - we must their inputs.
sasha
> Kai-Heng
>
> > --Dima
> > ---------------------------------------------------------------------
> > Intel Israel (74) Limited
> >
> > This e-mail and any attachments may contain confidential material for
> > the sole use of the intended recipient(s). Any review or distribution
> > by others is strictly prohibited. If you are not the intended
> > recipient, please contact the sender and delete all copies.