Re: [regression] Touchpad is not working after suspend to RAM since kernel 5.14 (fwd from b.k.o bug 214667) #forregzbot

[Thorsten Leemhuis <regressions@leemhuis.info>]

On 20.01.22 09:17, Thorsten Leemhuis wrote:
> On 28.12.21 08:29, Thorsten Leemhuis wrote:
>> Hi, this is your Linux kernel regression tracker speaking.
>>
>> Forwarding a regression reported by Christian Casteyde (CCed) in
>> bugzilla.kernel.org which apparently has fallen through the cracks.
>>
>> https://bugzilla.kernel.org/show_bug.cgi?id=214667
>>
>> A few quotes from comments in the ticket:
> 
> A quote from https://bugzilla.kernel.org/show_bug.cgi?id=214667#c13
> 
> ```
>> I confirm reverting this commit on kernel 5.15.14 fixes the issue:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=498d0ddc6ae931e4e79a57c56b6dd4576aa435b6
> ```
> So for the record update the culprit in regzbot:
> 
> #regzbot introduced 498d0ddc6ae931e4

#regzbot invalid: Reporter stated after debugging with developer: as far
as the suspend failure on my laptop is concerned, this is another bug
and not a regression.

https://bugzilla.kernel.org/show_bug.cgi?id=214667#c26

"""
I'm quite convinced the original commit is right.
IMHO, what is missing is correct handling of suspend failure (whatever
the cause): if something is disabled before going to suspend, it must be
restored if suspend fails.
I don't know if the suspend framework makes that error handling easy,
but it makes sense to rollback any action started in the suspend process
if a step prevents this process from completing.
As far as the suspend failure on my laptop is concerned, this is another
bug and not a regression.
"""

Ciao, Thorsten (wearing his 'Linux kernel regression tracker' hat)

P.S.: As a Linux kernel regression tracker I'm getting a lot of reports
on my table. I can only look briefly into most of them. Unfortunately
therefore I sometimes will get things wrong or miss something important.
I hope that's not the case here; if you think it is, don't hesitate to
tell me about it in a public reply, that's in everyone's interest.

BTW, I have no personal interest in this issue, which is tracked using
regzbot, my Linux kernel regression tracking bot
(https://linux-regtracking.leemhuis.info/regzbot/). I'm only posting
this mail to get things rolling again and hence don't need to be CC on
all further activities wrt to this regression.



> TWIMC: this mail is primarily send for documentation purposes and for
> regzbot, my Linux kernel regression tracking bot. These mails usually
> contain '#forregzbot' in the subject, to make them easy to spot and filter.
> 
>>> Since Kernel 5.14 (probably 5.14-rc5 indeed) the touchpad does not
>>> work anymore after resume from suspend to RAM. Was working with 5.13
>>> kernel.
>>>
>>> I've bisected the bug, first bad commit is: 
>>> b3e29642548258c7cd2cb3326a776fff84cd6b69 is the first bad commit
>>>
>>> SC[33mcommit b3e29642548258c7cd2cb3326a776fff84cd6b69ESC[m Merge:
>>> 8f4ef88 498d0dd Author: Jiri Kosina <jkosina@suse.cz> Date:   Wed Jun
>>> 30 09:15:15 2021 +0200
>>>
>>> Merge branch 'for-5.14/multitouch' into for-linus
>>>
>>> - patch series that ensures that hid-multitouch driver disables touch
>>> and button-press reporting on hid-mt devices during suspend when the
>>> device is not configured as a wakeup-source, from Hans de Goede
>>>
>>> Seem to be related with the observed behaviour.
>>
>> Yes, that's a merge, but it contains code changes, maybe something went
>> wrong there.
>>
>>> Update with kernel 5.15-rc7
>>>
>>> Still present. However, I noticed dmesg ouput interesting messages
>>> telling there is a transfer from the ELAN touchpad while suspended,
>>> it failed to suspend, then failed to resume. The interesting thing is
>>> if I try to suspend a second time, at resume the touchpad manages to
>>> resume. Appending dmesg output for reference.
>>
>>
>>> The problem is still present in 5.16-rc7, but indeed it got worse
>>> (and indeed is now critical). a) After the first "suspend" tentative
>>> (closing the lid), the laptop doesn't suspend (only the screen is
>>> blanked) b) When I reopen the lid, the touchpad stays disabled c)
>>> When I try to suspend a second time (closing the lid), the system
>>> totally freeze (without any info in dmesg) and I need to reset it
>>> totally. I'll open a separate bug report for this one, when bisected,
>>> and will try to post it to the suspend maintainer together with the
>>> mailing list (I'm not accustomed to mailing lists).
>>
>> FWIW, Christian did this here:
>> https://lore.kernel.org/all/256689953.114854578.1640622738334.JavaMail.root@zimbra40-e7.priv.proxad.net/
>>
>>> FYI, if I remember well, reverting this single commit fixed the issue
>>> and the diff was making sense (try to disable the touchpad before
>>> going to sleep to prevent unexpected event from it while
>>> suspending... if I understood well the code).
>>
>> To be sure this issue doesn't again fall through the cracks unnoticed,
>> I'm adding it to regzbot, my Linux kernel regression tracking bot:
>>
>> #regzbot introduced b3e29642548258c7cd2cb3326a776fff84cd6b69ESC
>> #regzbot title hid: touchpad is not working after suspend to RAM
>> #regzbot from: Christian Casteyde <casteyde.christian@free.fr>
>> #regzbot ignore-activity
>>
>> Reminder: when fixing the issue, please add a 'Link:' tag with the URL
>> to the report (the parent of this mail) using the kernel.org redirector,
>> as explained in 'Documentation/process/submitting-patches.rst'. Regzbot
>> then will automatically mark the regression as resolved once the fix
>> lands in the appropriate tree. For more details about regzbot see footer.
>>
>> Sending this to everyone that got the initial report, to make all aware
>> of the tracking. I also hope that messages like this motivate people to
>> directly get at least the regression mailing list and ideally even
>> regzbot involved when dealing with regressions, as messages like this
>> wouldn't be needed then.
>>
>> Don't worry, I'll send further messages wrt to this regression just to
>> the lists (with a tag in the subject so people can filter them away), as
>> long as they are intended just for regzbot. With a bit of luck no such
>> messages will be needed anyway.
>>
>>
>>
>> Ciao, Thorsten (wearing his 'Linux kernel regression tracker' hat).
>>
>> P.S.: As a Linux kernel regression tracker I'm getting a lot of reports
>> on my table. I can only look briefly into most of them. Unfortunately
>> therefore I sometimes will get things wrong or miss something important.
>> I hope that's not the case here; if you think it is, don't hesitate to
>> tell me about it in a public reply. That's in everyone's interest, as
>> what I wrote above might be misleading to everyone reading this; any
>> suggestion I gave thus might sent someone reading this down the wrong
>> rabbit hole, which none of us wants.
>>
>> BTW, I have no personal interest in this issue, which is tracked using
>> regzbot, my Linux kernel regression tracking bot
>> (https://linux-regtracking.leemhuis.info/regzbot/). I'm only posting
>> this mail to get things rolling again and hence don't need to be CC on
>> all further activities wrt to this regression.
>>
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>>
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