[OpenAFS] some older openafs-client versions have started failing

[Benjamin Kaduk]

On Thu, 14 Jul 2016, Chad William Seys wrote:

> Hi Ben,
>
> The Scientific Linux clients are using patched (by Redhat) 2.6.32 and the
> Debian clients are using patched (by Debian) 3.2.78 and 3.16.7 .
>
> Do you suspect that a recent security patch, applied to all three kernels,
> could have broken the older AFS clients?

It has been known to happen.  (In particular, the "Linux kernel changes to
support interrupting splice operations." that Jeffrey mentions has been
heavily backported, since it is supposed to make some "hung" processes
more interruptible.  Not quite a security issue, but it made it into a lot
of distro kernels.)

> I could certainly test this idea if it appears promising.  I guess I'd start
> with the server's kernel though: One data point that argues against it being

I share Jeffrey's skepticism that the server's kernel version is relevant.

> the client's kernel is that for the Scientific Linux box I booted up an
> machine which had not been updated for a long time (kernel dated Mar 22, 2016)
> and compiled openafs 1.6.15 (not functional) and 1.6.16 (functional).

Just to be clear: those 1.6.15 and 1.6.16 were from-source builds of the
stock OpenAFS releases?

-Ben