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

From: Greg Kroah-Hartman
Date: Fri Jan 13 2017 - 08:00:20 EST


On Wed, Jan 11, 2017 at 03:26:06PM +0100, Paul Menzel wrote:
> 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 itâs 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.

I can duplicate this on my laptop here as well :(

Did you get anywhere with your bisection?

thanks,

greg k-h