On 05/19/2014 09:36 PM, Tony Lindgren wrote:
* Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> [140519 11:07]:
On 05/19/2014 07:51 PM, Tony Lindgren wrote:
* Santosh Shilimkar <santosh.shilimkar@xxxxxx> [140519 10:35]:
On Monday 19 May 2014 01:23 PM, Tony Lindgren wrote:
* Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> [140519 09:46]:
On 05/16/2014 11:29 PM, Tony Lindgren wrote:
And just to recap, this problem can be reproduced with current
Linux next with omap2plus_defconfig with CONFIG_CPU_IDLE enabled. The
system should hang during the boot at some point.
I can take the time to investigate a bit more but not right now. What is
your deadline before committing the reverts ?
Well we do have several automated build and boot systems failing
because of this with multi_v7_defconfig. And users are complaining,
see this report from Tobias Jakobi:
https://bugzilla.kernel.org/show_bug.cgi?id=75421
It seems that doing the revert is not enough based on the
page above.
Thats not true. The above link used the half patch and not the
updated patch. Updated patch worked for Alex also. As you can
see they saw RCU stalls and they go away after the updated patch.
Can you please point them to try out the updated patch ?
OK good point. I added a link to the updated patch in
bugzilla.
I'd prefer we'd fix this issue properly for sure, it seems that
we're not quite understanding what's going on. And this might
hit other platforms too when they start implementing deeper
PM idle states in the mainline kernel.
I am certain that the updated patch fixed the regression
for sure. The issue is really not generic enough since its related
an OMAP ROM errata which needs that special handling of
interrupt re-trigger etc. You don't need that for other platforms
so they are not likely get affected.
OK makes sense to me considering the ROM code. Daniel, are you OK
with that or do you still want to investigate further?
For the moment I am a bit short in time for some other tasks. So feel free
to apply the revert and I will look for a proper fix when I will have time.
Added Tobias to Cc. At the bugzilla link Tobias is saying
he used the right patch from Santosh to test and it still
fails.
So apparently Santosh, Kevin and Alex say they are not facing the issue
anymore with the revert. But Tobias is still facing this issue.
There is this simple program [1] which usually makes cpuidle to hang the
system more quickly when there is a problem somewhere. May be worth to
check with it.
Hope that helps.
-- Daniel
[1]
https://git.linaro.org/power/pm-qa.git/blob/HEAD:/cpuidle/cpuidle_killer.c
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
