Re: [tboot-devel] TBOOT 1.8.3 fails to resume from S3

[Ross P. <ros...@gm...>]

On 09/10/2015 03:35 PM, Ross Philipson wrote:
> I have been working on moving our project from TBOOT 1.7.0 to 1.8.3. I
> have discovered that while our 1.7.0 version of TBOOT resumes from S3
> just fine, 1.8.3 does not.
>
> The most common symptom seems to be a hang just after TBOOT enters SMX
> mode. The hang happens at different places so I don't think it is one
> specific thing that TBOOT is doing to cause the hang. The hang can be
> short (on the order of seconds) or longs (several minutes). Then
> suddenly the platform will "unhang". It looks like the platform restarts
> quickly and goes right back in to TBOOT but it is a little hard to tell
> exactly what happens right around this point. We see this on every
> system we have tried it on.
>
> I have backed all our patches out and I still see the problem with a
> clean 1.8.3 code base. I have also tried using TBOOT with a Debian
> Jessie install and I get similar problems there. I have been comparing
> the code between the version and have so far not found anything that
> makes a difference.
>
> Any help in this matter is appreciated.
> Thanks

I spent some time tracking this down today. If I build without these two 
patches, I no longer get a hang on resume from S3:

http://hg.code.sf.net/p/tboot/code/rev/9040e000ccc4
http://hg.code.sf.net/p/tboot/code/rev/78713e04bdd9

I have not identified the exact cause yet but I wanted to get these 
results posted to the list.

Thanks

-- 
Ross Philipson