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

[Jan Beulich <jbeulich@xxxxxxxx>]

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.

Jan