[U-Boot] [PATCH] common: nvedit to protect additional ethernet addresses Part 1/1

[Wolfgang Denk]

Dear Stefan Althoefer,

In message <ghhni0$6dv$1 at ger.gmane.org> you wrote:
>
> > That would be one way to avoid unnecessary tests.
> > 
> > Probably not the most elegant approach, agreed.
> > 
> > There are other options, though.
> 
> But your suggested optimizations will only be effective if someone tries to
> write to "serial#". This is not normally done (attempt can be considered
> an error).

Can it? What make you think so?

There are lots of boards that come fresh out  of  production  with  a
virgin  environment,  where  setting  "serial#" is a perfectly normal
thing, and not an error at all.

> If access to any nonprotected environment variables is requested (and speed
> does matter here) then any of the protected cases must be tested.

Yes, but you can do this in many different ways - more and less
efficient ones.

> Even you code:
> 
> --------
> if( "serial#" )
>    ...
> else if( "ethaddr" )
>    ...
> else if( "eth[0-9]+addr" )
>    ...
> ---------
> 
> then all the ifs are triggered if you write to "videomode".

Yes, we probably can agree that this is one  of  the  less  efficient
implementations  [I  take  it  as  pseudo code, because otherwise all
cases would execute the "if" branch.]


Best regards,

Wolfgang Denk

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