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

From: Hans de Goede
Date: Mon Jan 10 2022 - 09:58:22 EST


Hi,

On 1/10/22 14:00, Jiri Kosina wrote:
> On Tue, 28 Dec 2021, 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

Thanks, I will respond to this in the bugzilla ticket.

Regards,

Hans




>>
>> A few quotes from comments in the ticket:
>>
>>> 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@xxxxxxx> 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.
>
> CCing Hans, as that merge commit brought his series "disable touch and
> button-press during suspend" series.
>
> It's strange though that bisection points to a merge commit and not a
> commit in that series.
>
>>
>>> 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@xxxxxxxxxxxxxxxxxxxxxxxxxxx/
>>
>>> 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@xxxxxxx>
>> #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.
>>
>> ---
>> Additional information about regzbot:
>>
>> If you want to know more about regzbot, check out its web-interface, the
>> getting start guide, and/or the references documentation:
>>
>> https://linux-regtracking.leemhuis.info/regzbot/
>> https://gitlab.com/knurd42/regzbot/-/blob/main/docs/getting_started.md
>> https://gitlab.com/knurd42/regzbot/-/blob/main/docs/reference.md
>>
>> The last two documents will explain how you can interact with regzbot
>> yourself if your want to.
>>
>> Hint for reporters: when reporting a regression it's in your interest to
>> tell #regzbot about it in the report, as that will ensure the regression
>> gets on the radar of regzbot and the regression tracker. That's in your
>> interest, as they will make sure the report won't fall through the
>> cracks unnoticed.
>>
>> Hint for developers: you normally don't need to care about regzbot once
>> it's involved. Fix the issue as you normally would, just remember to
>> include a 'Link:' tag to the report in the commit message, as explained
>> in Documentation/process/submitting-patches.rst
>> That aspect was recently was made more explicit in commit 1f57bd42b77c:
>> https://git.kernel.org/linus/1f57bd42b77c
>>
>