Re: Resume from suspend broken in 3.15. (bisected)

From: Ken Moffat
Date: Wed May 28 2014 - 19:49:38 EST


On Wed, May 28, 2014 at 06:25:21PM +0100, Ken Moffat wrote:
> Hi Daniel,
>

[ correcting details, confirming that reverting this does fix the
problem, adding Cc:s ]

> I've only started full testing of 3.15 on one of my machines now
> that -rc7 has been released (this one had two issues in the radeon
> code, second was fixed in rc7). Unfortunately, suspend to RAM
> (pm-suspend), or rather the wake-up, is broken on this box [ my
> other two boxes are fine in rc7 ].
>
> Bisection identified one of your commits -
>
> commit 25f397a429dfa43f22c278d0119a60a343aa568f
> Author: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Date: Fri Jul 19 18:57:11 2013 +0200
>
> drm/crtc-helper: explicit DPMS on after modeset
>
> Atm the crtc helper implementation of set_config has really
> inconsisten semantics: If just an fb update is good enough, dpms state
> will be left as-is, but if we do a full modeset we force everything to
> dpms on.
>
> This change has already been applied to the i915 modeset code in
>
> ('git show' stops at that point)

update : I've no idea what was going on there, nor for the problem
with attempting to revert it. I've now gone back into git,
extracted the full commit to a file with 'git show', and then used
git apply -R to revert it from 3.15-rc7. That version wakes up from
suspend to RAM, 3.15-rc7 itself did not.

Maybe I was still in git log when I thought I was on the command
line. Anyway, snipping git's view of my failed attempt to revert
it, and adding Dan and Alex who were CC'd on the commit.

>
> The processor is an AMD A4 APU. The symptoms after this commit are
> that pm-suspend works (I invoke it from my keyboard's sleep key),
> i.e. the power LED on the case goes out and the monitor goes black
> and reports no signal. When I press a key to resume, the power LED
> comes on but the screen stays black. Magic-SysRQ does not work and
> I have to use the case switch to reboot. That results in filesystem
> errors which fsck fixes and warns about (probably, just a sign of
> unclean shutdown).
>
> The only thing in the log are a couple of messages from EXT4 at the
> end of putting the box to sleep -
> May 28 16:19:02 bluesbreaker kernel: [ 39.440859] EXT4-fs (sda10): re-mounted. Opts: commit=0
> May 28 16:19:02 bluesbreaker kernel: [ 39.592318] EXT4-fs (sda13): re-mounted. Opts: commit=0
> May 28 16:20:05 bluesbreaker syslogd 1.5.0: restart.
>
> What can I do to help debug this ?
>
Äen
--
Nanny Ogg usually went to bed early. After all, she was an old lady.
Sometimes she went to bed as early as 6 a.m.
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