Re: [PATCH] crypto: x86/camellia - Replace kernel.h with the necessary inclusions

[Christophe JAILLET]

Le 09/06/2022 à 12:15, Herbert Xu a écrit :
> On Sun, Jun 05, 2022 at 09:32:53AM +0200, Christophe JAILLET wrote:
> > When kernel.h is used in the headers it adds a lot into dependency hell,
> > especially when there are circular dependencies are involved.
> >
> > Replace kernel.h inclusion with the list of what is really being used.
> >
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> > ---
> >   arch/x86/crypto/camellia.h | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/crypto/camellia.h b/arch/x86/crypto/camellia.h
> > index 1dcea79e8f8e..547fb7e30928 100644
> > --- a/arch/x86/crypto/camellia.h
> > +++ b/arch/x86/crypto/camellia.h
> > @@ -4,7 +4,7 @@
> >   
> >   #include <crypto/b128ops.h>
> >   #include <linux/crypto.h>
> > -#include <linux/kernel.h>
> > +#include <linux/types.h>
> >   
> >   #define CAMELLIA_MIN_KEY_SIZE	16
> >   #define CAMELLIA_MAX_KEY_SIZE	32
>
> This is not sufficient.  For example, asmlinkage isn't explicitly
> defined by any of these header files so it would be relying on an
> implicit inclusion which is prone to breakage.

Agreed, I missed that.

> Did you audit the entire file?

Yes, but I missed the asmlinkage.

In fact, I've sent a few "obvious" (but nothing is never obvious at the 
end...) patches like that to see the interest.

I've spotted a few .h file with "easy to check" content.
Mostly #define, function declarations, a few u<something> datatypes.

Then, I made the #include simplification and compile tested the change.

If it worked, I consider that the patch looks fine.


In this particular case, I guess that the 'asmlinkage' should come from 
another #include when "camellia.h" is used.

My goal was not to introduce some new hidden constraints related to the 
order of the included .h. I just wanted to make them explicit (and 
complete) and start to simplify things.


As said, nothing is never obvious, and I'll stay away from this kind of 
changes :)


Thanks a lot for the review.

CJ



> Cheers,