* Re: Possible ACPI bug/regression in i2c-i801 [plain text]
2022-01-30 21:33 Possible ACPI bug/regression in i2c-i801 [plain text] Kim Nilsson
@ 2022-01-31 6:33 ` Thorsten Leemhuis
2022-02-01 15:56 ` Possible ACPI bug/regression in i2c-i801 Jean Delvare
1 sibling, 0 replies; 3+ messages in thread
From: Thorsten Leemhuis @ 2022-01-31 6:33 UTC (permalink / raw)
To: Kim Nilsson, jdelvare
Cc: linux-i2c, regressions@lists.linux.dev, stable@vger.kernel.org,
Greg KH
[TLDR: I'm adding this regression to regzbot, the Linux kernel
regression tracking bot; most text you find below is compiled from a few
templates paragraphs some of you might have seen already.]
Hi, this is your Linux kernel regression tracker speaking.
Adding the regression mailing list to the list of recipients, as it
should be in the loop for all regressions, as explained here:
https://www.kernel.org/doc/html/latest/admin-guide/reporting-issues.html
CCing Greg and Stable as well, as it's a stable regression.
On 30.01.22 22:33, Kim Nilsson wrote:
>
> I've recently been doing some suspend/resume testing related to an
> s2idle bug in amdgpu
> (https://gitlab.freedesktop.org/drm/amd/-/issues/1879) and I've come
> across some problems with C-states.
>
> After resuming from s2idle, Pkg(HW) will no longer enter any state C2 or
> deeper. Suspending to s3 would not trigger this issue on 5.16.2, but
> after trying out 5.16.4 I'm facing a similar problem where Pkg(HW) will
> rarely if ever go deeper than C3. Now, the reason I am contacting you is
> because I was playing around today and found that unloading i2c-i801
> seems to fix the issue.
Thanks for the report.
To be sure this issue doesn't fall through the cracks unnoticed, I'm
adding it to regzbot, my Linux kernel regression tracking bot:
#regzbot ^introduced v5.16.2..v5.16.4
#regzbot title i2c: Possible ACPI bug/regression in i2c-i801 [plain text]
#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.
> # CPU: Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz
> # GPU: Intel Corporation WhiskeyLake-U GT2 [UHD Graphics 620], Advanced
> Micro Devices, Inc. [AMD/ATI] Lexa XT [Radeon PRO WX 3100]
> # 00:15.0 Serial bus controller: Intel Corporation Cannon Point-LP
> Serial IO I2C Controller #0 (rev 30)
> # 00:15.1 Serial bus controller: Intel Corporation Cannon Point-LP
> Serial IO I2C Controller #1 (rev 300:19.0 Serial bus controller: Intel
> Corporation Cannon Point-LP Serial IO I2C Host Controller (rev 30)
>
>
> dmesg output when loading the module after an unload:
>
> [ 1002.961091] i801_smbus 0000:00:1f.4: SPD Write Disable is set
> [ 1002.961171] i801_smbus 0000:00:1f.4: SMBus using PCI interrupt
> [ 1002.961321] iTCO_wdt iTCO_wdt: unable to reset NO_REBOOT flag, device
> disabled by hardware/BIOS
> [ 1002.975399] i801_smbus 0000:00:1f.4: Accelerometer lis3lv02d is
> present on SMBus but its address is unknown, skipping registration
> [ 1002.975406] i2c i2c-10: 2/2 memory slots populated (from DMI)
> [ 1002.976713] ee1004 10-0050: 512 byte EE1004-compliant SPD EEPROM,
> read-only
> [ 1002.976808] i2c i2c-10: Successfully instantiated SPD at 0x50
>
>
> This is my first LKML bug report, so I could use some guidance in how to
> provide more information.
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.
---
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
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: Possible ACPI bug/regression in i2c-i801
2022-01-30 21:33 Possible ACPI bug/regression in i2c-i801 [plain text] Kim Nilsson
2022-01-31 6:33 ` Thorsten Leemhuis
@ 2022-02-01 15:56 ` Jean Delvare
1 sibling, 0 replies; 3+ messages in thread
From: Jean Delvare @ 2022-02-01 15:56 UTC (permalink / raw)
To: Kim Nilsson; +Cc: linux-i2c
Hi Kim,
On Sun, 30 Jan 2022 22:33:43 +0100, Kim Nilsson wrote:
> I've recently been doing some suspend/resume testing related to an
> s2idle bug in amdgpu
> (https://gitlab.freedesktop.org/drm/amd/-/issues/1879) and I've come
> across some problems with C-states.
Preliminary remark: having read this bug report and the long list of
kernel parameters you need to make it somewhat work, it seems that your
system is having a lot more problems than just i2c-i801 hypothetically
breaking ACPI. Kernel command line parameters are meant as ways to
workaround or debug issues, you shouldn't need them for regular
operation (in most cases). So for each command line parameter you need
to pass, you should report to the respective kernel development list
with enough details to have the problem investigated and fixed. It is
likely that the solution which will make it no longer mandatory to pass
the command line parameter will actually make the situation not the
same, but better than what you have now.
> After resuming from s2idle, Pkg(HW) will no longer enter any state C2 or
> deeper. Suspending to s3 would not trigger this issue on 5.16.2, but
> after trying out 5.16.4 I'm facing a similar problem where Pkg(HW) will
> rarely if ever go deeper than C3. Now, the reason I am contacting you is
> because I was playing around today and found that unloading i2c-i801
> seems to fix the issue.
I'm no expert in power management, but to be honest I can't make much
sense from the paragraph above.
1* How do you "resume from s2idle"? My understanding is that s2idle aka
S0 is just the normal power state where the kernel tries to let the
hardware go to low power run-time mode when possible. You would get in
and out of that state all the time when using the laptop. So please
explain what you mean exactly.
Also my understanding is that s2idle is not really related to ACPI.
2* What does "Pkg(HW)" mean?
3* How do you check the C states?
4* Which issue exactly does unloading i2c-i801 fix? The s2idle one, the
S3 one, both?
5* On which kernel did you try unloading the i2c-i801 module with the
results above? Can you reproduce this behavior with other kernel
versions?
6* You claim this is a regression, which implies this has worked at
some point in the past. Which kernel did you test where having the
i2c-i801 module loaded or not made no difference ?
7* Are you actually using the i2c-i801 module for anything?
As a summary, we will need a lot more details in order to be able to
investigate your report. Specifically, we need accurate data about what
you tested and what were the results, and enough data point to actually
draw conclusions. Something along the lines of: "I do <this> on kernel
<x.y.z> with boot parameters <foo> <bar>, and <that> happens. If I do
the same on kernel <x.a.b> with the same parameters, <something else>
happens. Ideally you would narrow it to just one single change (kernel
version, boot parameter, i2c-i801 being loaded or not...) so that we
have somewhere to start investigating.
> # CPU: Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz
> # GPU: Intel Corporation WhiskeyLake-U GT2 [UHD Graphics 620], Advanced
> Micro Devices, Inc. [AMD/ATI] Lexa XT [Radeon PRO WX 3100]
> # 00:15.0 Serial bus controller: Intel Corporation Cannon Point-LP
> Serial IO I2C Controller #0 (rev 30)
> # 00:15.1 Serial bus controller: Intel Corporation Cannon Point-LP
> Serial IO I2C Controller #1 (rev 300:19.0 Serial bus controller: Intel
> Corporation Cannon Point-LP Serial IO I2C Host Controller (rev 30)
The line above is clearly corrupted.
When reporting PCI device information, please use option -nn of lspci,
so that the device IDs are included. This makes it easier to
investigate.
Either way, none of the devices listed are driven by i2c-i801. The
device you are looking for would be named "Cannon Point-LP SMBus
Controller".
> dmesg output when loading the module after an unload:
>
> [ 1002.961091] i801_smbus 0000:00:1f.4: SPD Write Disable is set
> [ 1002.961171] i801_smbus 0000:00:1f.4: SMBus using PCI interrupt
> [ 1002.961321] iTCO_wdt iTCO_wdt: unable to reset NO_REBOOT flag, device
> disabled by hardware/BIOS
> [ 1002.975399] i801_smbus 0000:00:1f.4: Accelerometer lis3lv02d is
> present on SMBus but its address is unknown, skipping registration
> [ 1002.975406] i2c i2c-10: 2/2 memory slots populated (from DMI)
> [ 1002.976713] ee1004 10-0050: 512 byte EE1004-compliant SPD EEPROM,
> read-only
> [ 1002.976808] i2c i2c-10: Successfully instantiated SPD at 0x50
Is this complete? The last 2 lines should repeat for the second memory
slot. Anyway, none of these message show any ACPI-related problem.
--
Jean Delvare
SUSE L3 Support
^ permalink raw reply [flat|nested] 3+ messages in thread