Re: [XEN PATCH 05/13] automation/eclair: add deviation for usercopy.c

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

+Nicola, Luca

On Mon, 28 Aug 2023, Simone Ballarin wrote:
> xen/arch/x86/usercopy.c includes itself, so it is not supposed to
> comply with Directive 4.10:
> "Precautions shall be taken in order to prevent the contents of a
> header file being included more than once"
> 
> This patch adds a deviation for the file.
> 
> Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
>
> ---
>  automation/eclair_analysis/ECLAIR/deviations.ecl | 4 ++++
>  docs/misra/rules.rst                             | 2 ++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/automation/eclair_analysis/ECLAIR/deviations.ecl 
> b/automation/eclair_analysis/ECLAIR/deviations.ecl
> index 2681a4cff5..a7d4f29b43 100644
> --- a/automation/eclair_analysis/ECLAIR/deviations.ecl
> +++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
> @@ -96,6 +96,10 @@ conform to the directive."
>  -config=MC3R1.D4.10,reports+={safe, "first_area(text(^ \\* In this case, no 
> inclusion guards apply and the caller is responsible.*\\*/$, begin-1))"}
>  -doc_end
>  
> +-doc_begin="xen/arch/x86/usercopy.c includes itself: it is not supposed to 
> comply with the directive"
> +-config=MC3R1.D4.10,reports+={deliberate, 
> "all_area(all_loc(file("^xen/arch/x86/usercopy\\.c$")))"}
> +-doc_end
> +
>  #
>  # Series 5.
>  #
> diff --git a/docs/misra/rules.rst b/docs/misra/rules.rst
> index 4b1a7b02b6..45e13d0302 100644
> --- a/docs/misra/rules.rst
> +++ b/docs/misra/rules.rst
> @@ -62,6 +62,8 @@ maintainers if you want to suggest a change.
>       - Files that are intended to be included more than once do not need to
>         conform to the directive. Files that explicitly avoid inclusion guards
>         under specific circumstances do not need to conform the directive.
> +       xen/arch/x86/usercopy.c includes itself: it is not supposed to comply
> +       with the directive.


We need to find a consistent way to document this kind of deviations in
a non-ECLAIR specific way, without adding the complete list of
deviations to rules.rst.

Can we use safe.json and add an in-code comment at the top of
usercopy.c? E.g.:

diff --git a/xen/arch/x86/usercopy.c b/xen/arch/x86/usercopy.c
index b8c2d1cc0b..8bb591f472 100644
--- a/xen/arch/x86/usercopy.c
+++ b/xen/arch/x86/usercopy.c
@@ -1,3 +1,4 @@
+/* SAF-1-safe */
 /* 
  * User address space access functions.
  *

Otherwise, maybe we should extend safe.json to also have an extra field
with a list of paths. For instance see "files" below:

{
    "version": "1.0",
    "content": [
        {
            "id": "SAF-0-safe",
            "analyser": {
                "eclair": "MC3R1.R8.6",
                "coverity": "misra_c_2012_rule_8_6_violation"
            },
            "name": "Rule 8.6: linker script defined symbols",
            "text": "It is safe to declare this symbol because it is defined in 
the linker script."
        },
        {
            "id": "SAF-1-safe",
            "analyser": {
                "eclair": "MC3R1.D4.10"
            },
            "name": "Dir 4.10: files that include themselves",
            "text": "Files purposely written to include themselves are not 
supposed to comply with D4.10.",
            "files": ["xen/arch/x86/usercopy.c"]
        },
        {
            "id": "SAF-2-safe",
            "analyser": {},
            "name": "Sentinel",
            "text": "Next ID to be used"
        }
    ]
}