[OpenAFS-devel] afsd & libafs module version checking??

[Jeffrey Hutzelman]

On Saturday, December 10, 2005 10:51:05 AM -0800 Russ Allbery 
<rra@stanford.edu> wrote:

> Horst Birthelmer <horst@riback.net> writes:
>> On Dec 10, 2005, at 5:13 AM, Troy Benjegerdes wrote:
>
>>> Is there a good way we can put a version string in both afsd and the
>>> kernel module, and spit out a warning if they are mismatched?
>
>> I heard this many times in the past ;-)
>
>> It's just nobody did it yet.
>
> You also don't want the checking to be too tight, since it makes upgrades
> when you're using OS packages more difficult if the versions have to match
> exactly and normally it works fine.  Usually the kernel module is in its
> own separate package, and since you want to be able to have multiple
> kernel modules for different kernels installed at the same time, it's a
> bit tricky to ship afsd in the same package as the kernel module.
>
> Ideally, the interface should be backward-compatible, since it's not like
> we change the parameters often, but that may be too much work.

In all of the recent cases I know of where there have been incompatible 
changes in the afsd/libafs interface, backward compatibility would not have 
been difficult.  That it wasn't done was the result of unfortunate 
misjudgement, rather than any particular technical difficulty.

-- Jeff