Re: [XEN PATCH v2 3/3] eclair: add deviations of MISRA C Rule 5.5

[Dmytro Prokopchuk1 <dmytro_prokopchuk1@xxxxxxxx>]

Hi Jan and Stefano.

Could we proceed with ARM deviations only so far?
I understand Stefano's preferences, but it can unblock me to address 
next ARM violations.

BR, Dmytro.

On 7/14/25 10:55, Jan Beulich wrote:
> On 12.07.2025 03:13, Stefano Stabellini wrote:
>> On Fri, 11 Jul 2025, Nicola Vetrini wrote:
>>> On 2025-07-09 23:38, Dmytro Prokopchuk1 wrote:
>>>> MISRA C Rule 5.5 states that: "Identifiers shall
>>>> be distinct from macro names".
>>>>
>>>> Update ECLAIR configuration to deviate:
>>>> - clashes in 'xen/include/xen/bitops.h';
>>>> - clashes in 'xen/include/xen/irq.h';
>>>> - clashes in 'xen/common/grant_table.c'.
>>>>
>>>> Signed-off-by: Dmytro Prokopchuk <dmytro_prokopchuk1@xxxxxxxx>
>>>> ---
>>>>   automation/eclair_analysis/ECLAIR/deviations.ecl | 8 ++++++++
>>>>   docs/misra/deviations.rst                        | 8 ++++++++
>>>>   2 files changed, 16 insertions(+)
>>>>
>>>> diff --git a/automation/eclair_analysis/ECLAIR/deviations.ecl
>>>> b/automation/eclair_analysis/ECLAIR/deviations.ecl
>>>> index e8f513fbc5..a5d7b00094 100644
>>>> --- a/automation/eclair_analysis/ECLAIR/deviations.ecl
>>>> +++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
>>>> @@ -117,6 +117,14 @@ it defines would (in the common case) be already
>>>> defined. Peer reviewed by the c
>>>>   -config=MC3A2.R5.5,reports+={deliberate,
>>>> "any_area(decl(kind(function))||any_loc(macro(name(memcpy||memset||memmove))))&&any_area(any_loc(file(^xen/common/libelf/libelf-private\\.h$)))"}
>>>>   -doc_end
>>>>
>>>> +-doc_begin="Clashes between function names and macros are deliberate for
>>>> bitops functions, pirq_cleanup_check, update_gnttab_par and
>>>> parse_gnttab_limit functions
>>>> +and needed to have a function-like macro that acts as a wrapper for the
>>>> function to be called. Before calling the function,
>>>> +the macro adds additional checks or adjusts the number of parameters
>>>> depending on the configuration."
>>>> +-config=MC3A2.R5.5,reports+={deliberate,
>>>> "any_area(all_loc(file(^xen/include/xen/bitops\\.h$)))"}
>>>
>>> Bitops violations are not inside "xen/include/xen/bitops.h", but rather
>>> "xen/arch/x86/include/asm/bitops.h"
>>>
>>>> +-config=MC3A2.R5.5,reports+={deliberate,
>>>> "any_area(all_loc(file(^xen/include/xen/irq\\.h$))&&context(name(pirq_cleanup_check)&&kind(function)))"}
>>>
>>> I would rather do (untested)
>>>
>>> -config=MC3A2.R5.5,reports+={deliberate,
>>> "all_area(decl(name(pirq_cleanup_check))||macro(name(pirq_cleanup_check)))"}
>>>
>>>> +-config=MC3A2.R5.5,reports+={deliberate,
>>>> "any_area(all_loc(file(^xen/common/grant_table\\.c$))&&context(name(update_gnttab_par||parse_gnttab_limit)&&kind(function)))"}
>>>> +-doc_end
>>>> +
>>>
>>> same as above
>>>
>>
>> Thanks Nicola! The following deviations are enough and sufficient to
>> zero violations on both ARM and x86:
>>
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^xen/include/xen/bitops\\.h$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^xen/arch/x86/include/asm/bitops\\.h$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^.*/compat\\.c$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^.*/compat/.*$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^xen/arch/x86/x86_emulate/.*$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "any_area(all_loc(file(^xen/arch/x86/include/asm/genapic\\.h$)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(parse_gnttab_limit))||macro(name(parse_gnttab_limit)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(update_gnttab_par))||macro(name(update_gnttab_par)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(pirq_cleanup_check))||macro(name(pirq_cleanup_check)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(virt_to_maddr))||macro(name(virt_to_maddr)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(set_px_pminfo))||macro(name(set_px_pminfo)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(set_cx_pminfo))||macro(name(set_cx_pminfo)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(cpu_has_amd_erratum))||macro(name(cpu_has_amd_erratum)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(copy_to_guest_ll))||macro(name(copy_to_guest_ll)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(copy_from_guest_ll))||macro(name(copy_from_guest_ll)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(edd_put_string))||macro(name(edd_put_string)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(cpu_has_amd_erratum))||macro(name(cpu_has_amd_erratum)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(page_list_entry))||macro(name(page_list_entry)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(do_physdev_op))||macro(name(do_physdev_op)))"}
>> -config=MC3A2.R5.5,reports+={deliberate, 
>> "all_area(decl(name(do_platform_op))||macro(name(do_platform_op)))"}
>>
>> Jan, are you OK with it?
> 
> For many of them the scope (all_area) looks to be far too wide, especially
> for about everything involved in compat handling. I can only repeat that I
> think that we would be (far) better off not having wider than necessary
> deviations.
> 
> There are others which I may not understand, e.g. the genapic.h one. IOW I
> further think that such a change would need to come with a fair bit of
> explanation / justification.
> 
> Jan