Bug#711853: insserv: Design bug: rcN.d unstable and not, maintainable

[Alessandro Vesely]

On Thu 18/Apr/2019 12:43:24 +0200 Ian Jackson wrote:
> Dmitry Bogatov writes:
>> 
>> As far as I know, "A depends B, B depends A" situation is called
>> RC-critical bug.
> 
> If shipped by Debian but it can perhaps arise due to old packages,
> ad-hoc packages, etc.  I agree that it's wrong but ISTM that it is
> better not to break things if we don't need to.
> 
> But I think the current behaviour of insserv in this situation is to
> bomb out completely and refuse to operate, isn't it ?  So it already
> fails to disturb the existing symlinks ?


At least, that's what happens at mine.  I had to write a quick script to
overcome that, http://www.tana.it/sw/fix-init/.


> As for "stable sort":
> 
> So IMO if someone wants to send a patch which improves the algorithm
> so that it preserves more of the existing link ordering, when
> right now it doesn't care, we ought to consider it.  (We'd want to
> be sure it didn't have any meaningfully different behaviour in
> "normal" configurations.)


Rather than a patch, I'd consider an alternative executable.  The link above
displays a man page for the script.  I'm not advocating that script, as it has
many defects.  However, I like its man page and its options.  I don't think
sparse patches to insserv can result in similar behavior.


> Note that the existing scheme parallelises things when the
> dependencies permit, and we should not take a patch which fails to
> parallelise things just because the existing links aren't parallel.


Here's a point I had never considered.  Perhaps, that's because I tend to boot
very sparingly --even on laptops, since suspend works well enough.  I accept
parallelism can be a very important point for several people.  An instance of
diversity?


Best
Ale
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