Comment # 27 on bug 1051465 from Franck Bui

(In reply to Thomas Blume from comment #26)
> Upstream seems to prefer less string mangling in the rules and to favour
> using shell scripts instead (see comment#22).
> I would follow them in this case.

I'm not sure upstream claims that but I really prefer have the oneline shell
command embedded in the rule file. It doesn't really make sense to carry a
shell script that has a single command.

> 
> > ID_SERIAL or whatever that needs to be used, is supposed to be retrieved
> > from sysfs by using the "$attr{xxx}" syntax.
> 
> Yes, that's what the rule is doing.
>  
> > Please note that we should make sure to not pollute the environment that is
> > already setup by the upstream rules. Therefore setting ID_SERIAL or ID_MODEL
> > in 61-xxx is not a good idea.
> 
> Agreed, but can we be sure that the upstream rules always run before the
> compat rules?

Currently upstream rule file is named 60-xxx and ours is 61-xxx, so that should
be ok.

> I see it as a kind of security measure to also set ID_SERIAL in the compat
> rules. Since it takes the data from sysfs (just like the upstream rules do),
> we shouldn't overwrite something with wrong values.
> But that way we can be sure that the compat rules work, even if the upstream
> rules fail or are executed later.
> Does that make sense?

Well if upstream doesn't set them we shouldn't either and if they set it then
we can reuse them without doing any modifications.