Re: Debugging Thinkpad T430s occasional suspend failure.

[Hugh Dickins <hughd@google.com>]

On Tue, 12 Feb 2013, Dave Jones wrote:
> 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 ?

So far as I can tell.

> For me, as soon as I shut the lid, the moon light starts flashing indicating failure.

My moon light shines steadily.

> 
> 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..

Thanks, I'll give that a try this evening.

> 
>  > 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