VGA resume & thaw (wake up from S3 & S4) broken - kernel(nouveau) exclusively

[poma]

On 13.09.2014 23:46, Ilia Mirkin wrote:
> On Sat, Sep 13, 2014 at 5:25 PM, poma <pomidorabelisima at gmail.com> wrote:
>> On 13.09.2014 22:58, Ilia Mirkin wrote:
>>> On Sat, Sep 13, 2014 at 4:52 PM, poma <pomidorabelisima at gmail.com> wrote:
>>>> On 13.09.2014 07:02, poma wrote:
>>>>> On 13.09.2014 06:57, poma wrote:
>>>>>>
>>>>>> Actually I have nothing to show cause logs are all OK.
>>>>>> Haha, it seems to me that the bugs become intelligent.
>>>>>>
>>>>>> 3.15.10-201.fc20.x86_64
>>>>>> 3.16.2-200.fc20.x86_64
>>>>>> 3.17.0-0.rc4.git3.2.fc22.1.x86_64
>>>>>>  nouveau  [     DRM] suspending display...
>>>>>>  nouveau  [     DRM] unpinning framebuffer(s)...
>>>>>>  nouveau  [     DRM] evicting buffers...
>>>>>>  nouveau  [     DRM] waiting for kernel channels to go idle...
>>>>>>  nouveau  [     DRM] suspending client object trees...
>>>>>>  nouveau  [     DRM] suspending kernel object tree...
>>>>>> ...
>>>>>>  nouveau  [     DRM] re-enabling device...
>>>>>>  nouveau  [     DRM] resuming kernel object tree...
>>>>>>  nouveau  [   VBIOS][0000:02:00.0] running init tables
>>>>>>  nouveau  [  PTHERM][0000:02:00.0] fan management: automatic
>>>>>>  nouveau  [     CLK][0000:02:00.0] --: core 566 MHz shader 1400 MHz memory 399 MHz
>>>>>>  nouveau  [     DRM] resuming client object trees...
>>>>>>  nouveau  [     DRM] resuming display...
>>>>>>  nouveau 0000:02:00.0: no hotplug settings from platform
>>>>>>  nouveau 0000:02:00.0: no hotplug settings from platform
>>>>>>
>>>>>> Logs(dmesg) are literally identical.
>>>>>>
>>>>>> 3.15.10-201.fc20.x86_64 - nouveau(fb) resume & thaw PASSED, and that's all what works.
>>>>>>         Kernels >= 3.16 - nouveau(fb) resume & thaw BROKEN
>>>>>>             ALL Kernels - vesa(fb)    resume & thaw BROKEN.
>>>>>>
>>>>>>
>>>>>
>>>>> Excusez-moi,
>>>>> BROKEN == The display remains OFF.
>>>>>
>>>>
>>>> More precisely stated it looks like this:
>>>>
>>>> - Last kernel with working resume/thaw
>>>>   http://koji.fedoraproject.org/koji/buildinfo?buildID=538208
>>>>   kernel-3.16.0-0.rc0.git9.1.fc21
>>>>   2014-06-13
>>>>
>>>> - First kernel with broken resume/thaw
>>>>   kernel-3.16.0-0.rc0.git10.1.fc21
>>>>   http://koji.fedoraproject.org/koji/buildinfo?buildID=538244
>>>>   http://pkgs.fedoraproject.org/repo/pkgs/kernel/patch-3.15-git10.xz/f98fb42e79c966f8e139e27b61d933e0/patch-3.15-git10.xz
>>>>   2014-06-13
>>>>
>>>> The only difference in dmesg between working and broken kernel module with drm.debug=14 is
>>>>  [drm:drm_helper_hpd_irq_event] [CONNECTOR:18:DVI-I-1] status updated from connected to connected
>>>>  [drm:drm_helper_hpd_irq_event] [CONNECTOR:18:DVI-I-1] status updated from connected to connected
>>>>
>>>> - git commit probably introduced breakage
>>>>   drm/nouveau/disp: add internal representaion of output paths and connectors
>>>>   https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm?id=7a014a
>>>>   https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/drivers/gpu/drm/nouveau?id=7a014a
>>>>   2014-06-11
>>>
>>> Do you have any special reason to believe this to be the culprit
>>> (besides the fact that it has something to do with hpd)? Can you do an
>>> actual bisect to confirm?
>>>
>>> Thanks,
>>>
>>>   -ilia
>>
>> "hpd" what?
> 
> hpd = hotplug detect
> 
>> First Fedora Kernel with broken video resume/thaw aka FFKWBVRT i.e. kernel-3.16.0-0.rc0.git10.1.fc21
>> comes with 'patch-3.15-git10.xz' which closely resembles "git/commit/drivers/gpu/drm/nouveau?id=7a014a".
>> Simple as that.
> 
> I see. So no reason to believe that it's not e.g. 20014cb or 377b1f1
> or any one of the other patches pulled in by merge commit bc1dfff04a?
> 
>> Why are you asking me that bisect formality, man is it not enough that I tested two dozen kernels.
> 
> Doing a bisect would involve half as many kernels... Knowing the exact
> commit that breaks things is a fairly useful debug tactic, and
> drastically increases the chances that a problem gets fixed. Not sure
> why you're referring to it as a formality.
> 
> git bisect start v3.16-rc1 v3.15 -- drivers/gpu/drm/nouveau
> 
> (Pro tip: use a config tailored to your machine rather than a distro
> config if you want to spend 5 min/compile instead of 1 hour/compile)
> 
> Or you can wait and hope that someone else will have the same problem
> and works out the commit that causes it.
> 
> Or you can see if it has already been fixed in the latest kernels. Or
> try the experimental repo at
> http://cgit.freedesktop.org/~darktama/nouveau/ (a bit of a pain to
> build, unfortunately, you need some unknown kernel version to build
> against, usually ~latest works).
> 
> Good luck,
> 
>   -ilia
> 

Man, I am not a kernel developer, I do not understand what you're saying.
I did the best I could and spent a lot of time besides.
If that's not enough, so be it.
Thank you very much.


poma