Re: Debugging Thinkpad T430s occasional suspend failure.

From: Dave Jones
Date: Tue Feb 12 2013 - 19:41:13 EST


On Tue, Feb 12, 2013 at 04:26:22PM -0800, Hugh Dickins wrote:
> On Tue, 12 Feb 2013, Dave Jones wrote:
>
> > My Thinkpad T430s suspend/resumes fine most of the time. But every so often
> > (like one in ten times or so), as soon as I suspend, I get a black screen,
> > and a blinking power button.
> >
> > (Note: Not the capslock lights like when we panic, this laptop 'conveniently
> > doesn't have those. This is the light surrounding the power button, which afaik
> > isn't even OS controlled, so maybe we're dying somewhere in SMI/BIOS land?)
>
> Me too on T420s, except that is blessed with a blinking CapsLk.
>
> It's so erratic (though I think I see more failures than you do: I'd say
> a quick resume never fails, but an overnight resume fails half the time):
> I'm afraid I didn't have the patience to embark on pm_trace at all.

Sounds like yours successfully suspends all the time though ?
For me, as soon as I shut the lid, the moon light starts flashing indicating failure.

That said, we saw that I was failing on the resume path after a failed suspend,
so it could still be the same problem.

> I did try to bisect it during the -rc5 week. I'm not sure, but I have
> no record of seeing it on -rc1 or -rc2, but definitely saw it on -rc3.
> So I tried bisecting between -rc2 and -rc3, persisting for a day if it
> looked good; but the bisection didn't seem to be converging anywhere
> likely when -rc6 came out, and I switched to see if -rc6 solved it.
>
> I had no problem with -rc6; but with -rc7 it happens more than ever.
> Though still not on "quick" resumes, the kind you want to do when
> bisecting.

so I can hit this pretty quickly with this..

while [ 1 ];
do
rtcwake -s 5 -m no ; pm-suspend
done

Which should make it bisectable at least..

> Sharing these anecdotes in case they match or diverge from your
> experience and others, and might help towards finding the cause.
> Not-to-be-trusted bisection log appended: of course the bads are
> reliable, but perhaps none of the goods.

I didn't have this laptop pre 3.8rc, so I've not had a 'good' reference,
pretty sure I saw it during rc1 though, so I might have to go back further
a version or two.

Dave

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