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

[Greg Kroah-Hartman]

On Sun, Jan 15, 2017 at 07:19:03AM +0000, Winkler, Tomas wrote:
> > Subject: Re: [char-misc for 4.10-rc4 V2] mei: bus: enable OS version only for SPT
> > and newer
> > 
> > On Sat, Jan 14, 2017 at 08:27:31PM +0100, Paul Menzel wrote:
> > > Dear Greg,
> > >
> > >
> > > On 2017-01-13 14:00, Greg Kroah-Hartman wrote:
> > > > On Wed, Jan 11, 2017 at 03:26:06PM +0100, Paul Menzel wrote:
> > >
> > > > > 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 :(
> > >
> > > Which system do you have?
> > 
> > A Dell XPS13, don't know what cpu type it is, here's the output of one cpu from
> > /proc/cpuinfo
> > 
> > processor	: 3
> > vendor_id	: GenuineIntel
> > cpu family	: 6
> > model		: 78
> > model name	: Intel(R) Core(TM) i7-6560U CPU @ 2.20GHz
> > stepping	: 3
> > microcode	: 0x8a
> > cpu MHz		: 712.207
> > cache size	: 4096 KB
> > physical id	: 0
> > siblings	: 4
> > core id		: 1
> > cpu cores	: 2
> > apicid		: 3
> > initial apicid	: 3
> > fpu		: yes
> > fpu_exception	: yes
> > cpuid level	: 22
> > wp		: yes
> > flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca
> > cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx
> > pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl
> > xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor
> > ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic
> > movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm
> > 3dnowprefetch epb intel_pt tpr_shadow vnmi flexpriority ept vpid fsgsbase
> > tsc_adjust bmi1 avx2 smep bmi2 erms invpcid mpx rdseed adx smap clflushopt
> > xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify
> > hwp_act_window hwp_epp
> > bugs		:
> > bogomips	: 4419.34
> > clflush size	: 64
> > cache_alignment	: 64
> > address sizes	: 39 bits physical, 48 bits virtual
> > power management:
> > 
> > > > Did you get anywhere with your bisection?
> > >
> > > Sorry, I replied to a different message with my status.
> > >
> > > Please see my status below. Iâll have access to the machine on Monday
> > again.
> > >
> > > ```
> > > $ git bisect log
> > > git bisect start
> > > # good: [69973b830859bc6529a7a0468ba0d80ee5117826] Linux 4.9 git
> > > bisect good 69973b830859bc6529a7a0468ba0d80ee5117826
> > > # good: [69973b830859bc6529a7a0468ba0d80ee5117826] Linux 4.9 git
> > > bisect good 69973b830859bc6529a7a0468ba0d80ee5117826
> > > # bad: [a121103c922847ba5010819a3f250f1f7fc84ab8] Linux 4.10-ârc3 git
> > > bisect bad a121103c922847ba5010819a3f250f1f7fc84ab8
> > > # bad: [72cca7baf4fba777b8ab770b902cf2e08941773f] Merge tag
> > > 'staging-4.10-rc1' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
> > > git bisect bad 72cca7baf4fba777b8ab770b902cf2e08941773f
> > > # good: [b8d2798f32785398fcd1c48ea80c0c6c5ab88537] Merge tag 'clk-for-
> > linus'
> > > of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
> > > git bisect good b8d2798f32785398fcd1c48ea80c0c6c5ab88537
> > > # good: [9439b3710df688d853eb6cb4851256f2c92b1797] Merge tag 'drm-
> > for-v4.10'
> > > of git://people.freedesktop.org/~airlied/linux
> > > git bisect good 9439b3710df688d853eb6cb4851256f2c92b1797
> > > ```
> > >
> > 
> > You are close!  I'll try bisection tomorrow if I have some spare time.
> > 
> > thanks,
> 
> Greg,  is that same Laptop mode as Paul's, you've experience the issue on?

It's the same model name, but as this model has been shipped with many
different CPU versions over the years, I'm not sure if it is the exact
same one.

thanks,

greg k-h