Re: [char-misc for 4.10-rc4 V2] mei: bus: enable OS version only for SPT and newer

[Paul Menzel]

Dear Tomas,


On 01/11/17 15:12, Winkler, Tomas wrote:

> > > On 01/11/17 10:24, Winkler, Tomas wrote:
> > > > > On Wed, Jan 11, 2017 at 01:27:21AM +0200, Tomas Winkler wrote:
> > > > > > On older platforms the command should be just ignored by the
> > > > > > firmware but some older platforms misbehave so it's safer to send
> > > > > > the command only if required.
> > > > >
> > > > > Thanks! This fixes suspend-to-ram for me (on a Thinkpad x201s).
> > > >
> > > > What about Dell XPS13?
> > >
> > > With Linus' master branch from today, and Greg's char-misc-linus
> > > merged
> > > (Merge: 807b93e995d1 546cf3ef9c92), the regression is still there.
> >
> > Hmm, this should work on KBL....
> >
> > > I am now building a Linux kernel image with the two commits touching
> > > `bus- fixup.c` reverted.
> >
> > Thanks for the effort.
> >
> > > Do you want me to open a separate bug report for that, or continue
> > > debugging in the existing report [1], which is currently marked as resolved?
> >
> > Let's get some more data, shouldn't take long time.
> > > Do you have Kaby Lake devices sitting around for testing?
> >
> > We will of course try to reproduce the issue locally.
>
> Paul, currently we cannot reproduce this issue on Kaby Lake platforms on our side,

It looks like it’s a different issue. Reverting the two commits touching 
`bus-fixup.c`, did not help.

> we would be great for more debug data from your side.
> You can get more info by enabling  mode debug logs
>
> echo -n 'module mei +lfp' > /sys/kernel/debug/dynamic_debug/control
> echo -n 'module mei_me +lfp' > /sys/kernel/debug/dynamic_debug/control

I am currently bisecting to find the culprit. 13 steps will take some 
time though.

Tomas, I believe Intel’s “ACPI department” got access to a Dell XPS13.


Kind regards,

Paul