recent 2.6.26 kernel hangs at suspend

recent 2.6.26 kernel hangs at suspend

[Jeff Chua]

I can simulate this and it's definitely a bug, but I could only bisect
up to a point and the kernel would not boot after tat.

The bug is that my X60s notebook would not suspend-to-ram on the 2nd try.

Boot up -> suspend to ram -> ok -> resume -> suspend to ram -> hang!

The hang would only happen while in X.

If I don't enter X, it'll not hang on suspend to ram.

I tried git bisect but can only get to this commit
4a27214d7be31e122db4102166f49ec15958e8e9.

The next commit b82287587ef9917afbea5fcbf7aa63424b6f3719 would not boot.

How can I get pass the "bad" commit. I've tried "skip" or "next", but
still won't boot.

And it doesn't seem like it's X as 2.6.25 kernel can suspend and
resume many times in X without problem.

Here's how I bisected ...

git-bisect start
# bad: [b8291ad07a7f3b5b990900f0001198ac23ba893e] Linux 2.6.26-rc3
git-bisect bad b8291ad07a7f3b5b990900f0001198ac23ba893e
# good: [4b119e21d0c66c22e8ca03df05d9de623d0eb50f] Linux 2.6.25
git-bisect good 4b119e21d0c66c22e8ca03df05d9de623d0eb50f
# good: [c328d54cd4ad120d76284e46dcca6c6cf996154a] Merge
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb
git-bisect good c328d54cd4ad120d76284e46dcca6c6cf996154a
# bad: [25a025863e024f6b86b48137b10b4960c50351b0] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
git-bisect bad 25a025863e024f6b86b48137b10b4960c50351b0
# bad: [62d9f0dbc92d7e398fde53fc6021338393522e68] KVM: add ioctls to
save/store mpstate
git-bisect bad 62d9f0dbc92d7e398fde53fc6021338393522e68
# good: [ce1d5b23a8d1e19866ab82bdec0dc41fde5273d8] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
git-bisect good ce1d5b23a8d1e19866ab82bdec0dc41fde5273d8
# good: [a2826190aa157a1d29bef70ca81f8b51a9b36d29] IDE: Coding Style
fixes to drivers/ide/pci/it8213.c
git-bisect good a2826190aa157a1d29bef70ca81f8b51a9b36d29
# bad: [9b79ed952bd7344d40152f8a560ad8a0d93f3886] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-generic-bitops-v3
git-bisect bad 9b79ed952bd7344d40152f8a560ad8a0d93f3886
# bad: [4a27214d7be31e122db4102166f49ec15958e8e9] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-fixes
git-bisect bad 4a27214d7be31e122db4102166f49ec15958e8e9
# bad: [b82287587ef9917afbea5fcbf7aa63424b6f3719] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-misc
git-bisect bad b82287587ef9917afbea5fcbf7aa63424b6f3719


Thanks,
Jeff.

Re: recent 2.6.26 kernel hangs at suspend

[Linus Torvalds]

On Mon, 19 May 2008, Jeff Chua wrote:
> 
> How can I get pass the "bad" commit. I've tried "skip" or "next", but
> still won't boot.

Try

	git bisect visualize

and pick any commit that is active (avoiding the endpoints) and looks like 
a good candidate to test. Then do "git reset --hard <that-commit>" and try 
again..

Of course, when there are two overlapping bugs, and the other hides the 
bug you are trying to chase down, there *will* be cases where bisect 
simply doesn't work, if you are unlucky. Bisecting is wonderful, but it's 
not going so solve world hunger, or even be able to help with _all_ 
problems.

			Linus

Re: recent 2.6.26 kernel hangs at suspend

[Jeff Chua]

On Mon, May 19, 2008 at 11:26 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
>        git bisect visualize
>
> and pick any commit that is active (avoiding the endpoints) and looks like
> a good candidate to test. Then do "git reset --hard <that-commit>" and try

Trying that now.

Thanks,
Jeff.

Re: recent 2.6.26 kernel hangs at suspend

[Len Brown]

On Monday 19 May 2008, Jeff Chua wrote:
> I can simulate this and it's definitely a bug, but I could only bisect
> up to a point and the kernel would not boot after tat.
> 
> The bug is that my X60s notebook would not suspend-to-ram on the 2nd try.
>
> Boot up -> suspend to ram -> ok -> resume -> suspend to ram -> hang!
> 
> The hang would only happen while in X.

Does this notebook have intel graphics?
If yes, does anything change with the i915 driver loaded vs not loaded?

-Len

Re: recent 2.6.26 kernel hangs at suspend

[Jeff Chua]

On Tue, May 20, 2008 at 2:38 AM, Len Brown <lenb@kernel.org> wrote:
> On Monday 19 May 2008, Jeff Chua wrote:

> Does this notebook have intel graphics?

Yes.

(II) intel(0): Integrated Graphics Chipset: Intel(R) 945GM

> If yes, does anything change with the i915 driver loaded vs not loaded?

I'll try that. Currently, everything compliled into kernel.

Thanks,
Jeff.

Re: recent 2.6.26 kernel hangs at suspend

[Len Brown]

On Monday 19 May 2008, Jeff Chua wrote:
> On Tue, May 20, 2008 at 2:38 AM, Len Brown <lenb@kernel.org> wrote:
> > On Monday 19 May 2008, Jeff Chua wrote:
> 
> > Does this notebook have intel graphics?
> 
> Yes.
> 
> (II) intel(0): Integrated Graphics Chipset: Intel(R) 945GM
> 
> > If yes, does anything change with the i915 driver loaded vs not loaded?
> 
> I'll try that. Currently, everything compliled into kernel.


Another thing to check out is if VT switching is working.
On the Toshiba U305, which also has Intel graphics, it broke
and made suspend/resume look broken:

http://bugzilla.kernel.org/show_bug.cgi?id=10620

Re: recent 2.6.26 kernel hangs at suspend

[Pavel Machek]

Hi!

> I can simulate this and it's definitely a bug, but I could only bisect
> up to a point and the kernel would not boot after tat.
> 
> The bug is that my X60s notebook would not suspend-to-ram on the 2nd try.
> 
> Boot up -> suspend to ram -> ok -> resume -> suspend to ram -> hang!
> 
> The hang would only happen while in X.
> 
> If I don't enter X, it'll not hang on suspend to ram.

Ok, so we have X in the mix.

Can you try if it happens if you disable Intel framebuffer driver?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: recent 2.6.26 kernel hangs at suspend

[Jeff Chua]

On Tue, May 20, 2008 at 3:48 PM, Pavel Machek <pavel@suse.cz> wrote:

>> If I don't enter X, it'll not hang on suspend to ram.
>
> Ok, so we have X in the mix.
>
> Can you try if it happens if you disable Intel framebuffer driver?

The whole problem went away after the latest git pull.

Looks like the commit below fixes the problem of failing on 2nd suspense.

I've tested whole day and it's suspending-resuming after many cycles.

Sorry, couldn't get to email whole day. Traveling. Slow train.

Thank you all for your help!!!
Jeff.


commit 860da5e578c25d1ab4528c0d1ad13f9969e3490f
Merge: 1bf9947... e948e99...
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon May 19 13:30:40 2008 -0700

    Merge branch 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/
airlied/drm-2.6

    * 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm
-2.6:
      drm/i915: save and restore dsparb and d_state registers.
      drm/i915: fix off by one in VGA save/restore of AR & CR regs.
      drm: disable tasklets not IRQs when taking the drm lock spinlock
      Revert "drm/vbl rework: rework how the drm deals with vblank."