Comment # 3 on bug 917221 from John Leys

(In reply to Takashi Iwai from comment #1)
> My wild guess is the nouveau driver breakage.  We've got many bug reports
> regarding S3/S4 with nouveau, unfortunately.
> 
> Could you try the newer kernels in OBS Kernel:stable repo?

I installed the latest OBS stable kernel, but with no success.
# uname -r
3.19.0-1.g8a7d5f9-desktop

The symptoms are exactly as before.  I will keep this kernel a bit longer to
see if the problem happens less frequently with this kernel, but my guess is
that it makes no difference.  I only installed the minimal set of packages
required to install the new kernel, so did not update the libdrm_nouveau
package.