Bug 7408

Summary:	T60 stops triggering any ACPI events
Product:	Drivers	Reporter:	mst (mst)
Component:	Platform	Assignee:	acpi_acpica-core (acpi_acpica-core)
Status:	CLOSED PATCH_ALREADY_AVAILABLE
Severity:	normal	CC:	acpi-bugzilla
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6.19-rc3	Subsystem:
Regression:	---	Bisected commit-id:
Attachments:	Here's my .config for 2.6.19 Here's the config for 2.6.18.1 that works well patch to ibm_acpi.c

Description mst 2006-10-24 11:50:08 UTC

Most recent kernel where this bug did not occur:2.6.18.1 + patch
http://lkml.org/lkml/2006/7/20/56

Distribution:kubuntu 6.06 LTS
Hardware Environment: T60 with intel graphics. See
                      http://www.thinkwiki.org/wiki/Hardware_Specifications
                      BIOS at default setting - disk running in ahci mode
                      (this is why I need a patch for 2.6.18).
Software Environment:
Not sure what to put here. Seems to happen both with and without X running.
Problem Description:

after I do a full kernel compile, my T60 stops triggering any ACPI events:
tail -f /var/log/acpid does not show anything, even on Fn/F4 which is supposed
to be always enabled.  Restarting the acpid doesn't do anything either - ACPI
starts working again, for a while, only after reboot.

Works fine in 2.6.18 ( + this patch http://lkml.org/lkml/2006/7/20/56).


Steps to reproduce:
cd tmp
git clone -s ~/scm/linux-2.6
cd linux-2.6

make oldconfig
make -j 4

no new ACPI events reported after this.

Comment 1 mst 2006-10-24 11:52:19 UTC

Created attachment 9338 [details]
Here's my .config for 2.6.19

I attached the .config for 2.6.19-rc3 with which I see the problem

Comment 2 mst 2006-10-24 11:53:36 UTC

Created attachment 9339 [details]
Here's the config for 2.6.18.1 that works well

I attached the .config for 2.6.18 (that works well) for reference

Comment 3 Martin Lorenz 2006-10-25 00:06:28 UTC

I see on my X60s too but triggered by suspend-to-ram/resume. kernel compiling
did not yet show this behaviour (but I diden't really check for I usually reboot
rather quickly after compiling/installing a new kernel)

the problem is there since the first post 2.6.18 version that I compiled a few
weeks ago.

currently I run 2.6.18 with some patches, which suspends/resumes fine.

Comment 4 mst 2006-10-25 23:52:29 UTC

Yes, I see this too if I do not enable
IB thinkpad laptop extras under PM/ACPI -
in that case, kernel compile does not trigger the bug,
but suspend/resume does.

Comment 5 Len Brown 2006-10-29 20:11:02 UTC

> Yes, I see this too if I do not enable
> IB thinkpad laptop extras under PM/ACPI -
> in that case, kernel compile does not trigger the bug

So the "no ACPI events after kernel build" regression
happens only if ibm_acpi is loaded?

> but suspend/resume does.

So ACPI events used to work in 2.6.18 after suspend/resume,
but do not work after suspend/resume in 2.6.19 -- and
this is true not matter if ibm_acpi is loaded or not?

Comment 6 mst 2006-10-30 05:27:49 UTC

> > Yes, I see this too if I do not enable
> > IB thinkpad laptop extras under PM/ACPI -
> > in that case, kernel compile does not trigger the bug
> 
> So the "no ACPI events after kernel build" regression
> happens only if ibm_acpi is loaded?

Yes, it seems so.

> > but suspend/resume does.
> 
> So ACPI events used to work in 2.6.18 after suspend/resume,
> but do not work after suspend/resume in 2.6.19 -- and
> this is true not matter if ibm_acpi is loaded or not?

This is true if ibm_acpi is not loaded. I did not test this with
ibm_acpi loaded.

Comment 7 Len Brown 2006-11-02 23:53:40 UTC

Created attachment 9401 [details]
patch to ibm_acpi.c

There has been only 1 small patch to ibm_acpi.c between 2.6.18.1
and now.  If you patch -Rp1 this commit, you'll be backing that
driver down to the version that worked in 2.6.18,
and the 2.6.19 run-time issue with ibm_acpi should go away -- yes?

However, it isn't clear that this simple patch to clear the experimental
flag could be the root of the run-time errors; and maybe we need to
re-confirm the assertion that the run-time (not the suspend-time) failure...
1. does not happen in 2.6.18 with ibm_acpi loaded
2. does not happen in 2.6.19 with ibm_acpi unloaded
3. only happens in 2.6.19 with ibm_acpi loaded

Comment 8 mst 2006-11-05 05:21:26 UTC

OK, it seems Linus has zeroed in on the bug:
http://lkml.org/lkml/2006/11/1/84

I am running f9dadfa71bc594df09044da61d1c72701121d802
and no issues yet in several days of use.