Bug#890950: initramfs-tools: Resuming from hibernated swapfile fails

[<Mario.Limonciello@dell.com>]

Thanks, I appreciate your feedback.  
Some more comments nested below.
> >
> > 1) It requires that uswpswp is installed (to provide /bin/resume)[...]

> 
> No, it runs /bin/resume which is installed by klibc-utils.  (uswsusp
> installs its resume implementation as /sbin/resume.  That's what the
> comment is about.)

Ah thanks - this wasn't clear.  I wasn't seeing /bin/resume on a standard
system and that's because it's in /usr/lib/klibc/bin/resume on a standard
system and copied to initramfs.

> 
> > 2) It doesn't properly detect offsets
> 
> So far as I can see, the kernel has never really supported an offset
> being passed through /sys/power/resume.  However:
> 
> 1. The kernel parses the resume_offset parameter, and uses that for
> every resume request.
> 2. The implementation of /sys/power/resume is not very strict, and
> ignores the trailing ":offset".
> 
> This second feature was briefly broken between Linux 4.1-rc1 and 4.1-
> rc3, but otherwise still seems to work.  So I don't see what your
> change is fixing.
> 
> However I do think that either:
> 
> 1. The kernel should add real support for setting the resume offset
> after boot.
> 2. klibc should stop writing the unused offset parameter.

If you don't mind, I'm going to follow up with an updated patch
that drops klibc /bin/resume writing the unused parameter.

Also there was a few other aspects of my patch that I think are relevant
that I'll make sure are still present when I follow up.

1) using Plymouth if present to indicate resuming
2) Detection of swapfile via blkid (the current "auto") stuff doesn't work
otherwise.