Re: [RFC PATCH 4/4] xen: Justify linker script defined symbols in include/xen/kernel.h

[Julien Grall <julien@xxxxxxx>]

On 07/11/2022 12:56, Jan Beulich wrote:
> On 07.11.2022 12:53, Luca Fancellu wrote:
> > > On 7 Nov 2022, at 11:49, Jan Beulich <jbeulich@xxxxxxxx> wrote:
> > > On 07.11.2022 11:47, Luca Fancellu wrote:
> > > > --- a/xen/include/xen/kernel.h
> > > > +++ b/xen/include/xen/kernel.h
> > > > @@ -65,24 +65,28 @@
> > > >         1;                                      \
> > > > })
> > > >
> > > > +/* SAF-0-safe R8.6 linker script defined symbols */
> > > > extern char _start[], _end[], start[];
> > > > #define is_kernel(p) ({                         \
> > > >      char *__p = (char *)(unsigned long)(p);     \
> > > >      (__p >= _start) && (__p < _end);            \
> > > > })
> > > >
> > > > +/* SAF-0-safe R8.6 linker script defined symbols */
> > > > extern char _stext[], _etext[];
> > > > #define is_kernel_text(p) ({                    \
> > > >      char *__p = (char *)(unsigned long)(p);     \
> > > >      (__p >= _stext) && (__p < _etext);          \
> > > > })
> > > >
> > > > +/* SAF-0-safe R8.6 linker script defined symbols */
> > > > extern const char _srodata[], _erodata[];
> > > > #define is_kernel_rodata(p) ({                  \
> > > >      const char *__p = (const char *)(unsigned long)(p);     \
> > > >      (__p >= _srodata) && (__p < _erodata);      \
> > > > })
> > > >
> > > > +/* SAF-0-safe R8.6 linker script defined symbols */
> > > > extern char _sinittext[], _einittext[];
> > > > #define is_kernel_inittext(p) ({                \
> > > >      char *__p = (char *)(unsigned long)(p);     \
> > > Why the "R8.6" everywhere here? Didn't we agree that the in-code
> > > comments should be tool-agnostic?
> > The R8.6 is not tool specific, it is to give the quick hint that we are 
> > deviating
> > from MISRA Rule 8.6.
> Well, yes, "tool" was wrong for me to write. Imo references to a specific
> spec should equally be avoided in in-code comments, as other specs may
> turn up.
+1. The comment duplication is not great and sometimes even a short 
explanation it may not fit in 80 characters (AFAICT the justification 
should be a one line comment).
Cheers,

--
Julien Grall