Comment # 6 on bug 917221 from John Leys

(In reply to Takashi Iwai from comment #4)
> Then for identifying whether it's a nouveau issue, just boot with nomodeset,
> and do S4 and S3.  The graphics won't work, so you can do with vga=none, and
> check the remote login whether suspend/resume works.  If the same problem
> shows, the problem is in another place.
> 
> In anyway, please give hwinfo output.

I tried with vga=none and nomodeset in the default grub2 entry.  The result was
a video mode that was not correct (my monitor is 1920x1080 but the video mode
was 1280x1024)  But there was video, so it may be that i did not achieve what
you had wanted, since the nouveau driver was still installed and active.  The
resume still failed and now it is looking like more of a random failure, i.e.
unrelated to time since hibernation.  Initially, it looked like this resolved
the problem, but after a few tries, the problem reoccurred.

With the vga=none, however, there was no splash screen and what was displayed
during resume that failed was the same as the first few lines of the boot log:
       Started Show Plymouth Boot Screen.
[ OK ] Reached target Paths.
[ OK ] Reached target Basic System.
[ OK ] Found device ST2000DM001-1ER1.
[ OK ] Found device ST2000DM001-1ER1.
[ OK ] Found device /dev/disk/by-uuid/1ee0c6d1-4bc1-41ff-9827-951d337c181c.
[ OK ] Started dracut initqueue hook.
       Starting dracut pre-mount hook...
[ OK ] Reached target Remote File Systems (Pre).
[ OK ] Reached target Remote File Systems.

It was not possible to log in remotely, nor even ping the machine.

In looking around, it seems that there have been problems with having grub2 on
BTRFS because of the file structure of BTRFS, see
https://bugzilla.opensuse.org/show_bug.cgi?id=856391, and i wonder if this
could be related to my problem.