Resend: [PATCH] arm/gic_v3: fix MISRA C R2.1 violations in gicv3_do_LPI()

[Dmytro Prokopchuk1 <dmytro_prokopchuk1@xxxxxxxx>]

Hello,
looking forward to feedback, suggestions, or any required
changes to get this patch accepted.

BR, Dmytro.

On 9/29/25 22:55, Dmytro Prokopchuk1 wrote:
> The function 'gicv3_do_LPI()' violates MISRA C 2012 Rule 2.1, which states:
> "A project shall not contain unreachable code." This is due to the use of
> the 'BUG()' macro, which causes the function to never return.
>
> This behavior is intentional and safe within the specific build configuration
> defined by 'CONFIG_HAS_ITS'. The 'BUG()' macro handles irrecoverable error
> conditions where LPIs must not occur without an ITS enabled.
>
> A SAF comment has been added to document the justification for this violation,
> stating that it is safe within the context of the Xen project.
>
> Signed-off-by: Dmytro Prokopchuk <dmytro_prokopchuk1@xxxxxxxx>
> ---
> Test CI pipeline:
> https://gitlab.com/xen-project/people/dimaprkp4k/xen/-/pipelines/2070455717
> ---
>   docs/misra/safe.json                  | 8 ++++++++
>   xen/arch/arm/include/asm/gic_v3_its.h | 1 +
>   2 files changed, 9 insertions(+)
>
> diff --git a/docs/misra/safe.json b/docs/misra/safe.json
> index 3584cb90c6..4c227c1e8b 100644
> --- a/docs/misra/safe.json
> +++ b/docs/misra/safe.json
> @@ -124,6 +124,14 @@
>           },
>           {
>               "id": "SAF-15-safe",
> +            "analyser": {
> +                "eclair": "MC3A2.R2.1"
> +            },
> +            "name": "Rule 2.1: Unreachable code",
> +            "text": "It is safe because the BUG() macro is intentionally 
> used to terminate execution when LPIs are enabled without an ITS."
> +        },
> +        {
> +            "id": "SAF-16-safe",
>               "analyser": {},
>               "name": "Sentinel",
>               "text": "Next ID to be used"
> diff --git a/xen/arch/arm/include/asm/gic_v3_its.h 
> b/xen/arch/arm/include/asm/gic_v3_its.h
> index fc5a84892c..672dae7ac3 100644
> --- a/xen/arch/arm/include/asm/gic_v3_its.h
> +++ b/xen/arch/arm/include/asm/gic_v3_its.h
> @@ -229,6 +229,7 @@ static inline unsigned int vgic_v3_its_count(const struct 
> domain *d)
>       return 0;
>   }
>
> +/* SAF-15-safe */
>   static inline void gicv3_do_LPI(unsigned int lpi)
>   {
>       /* We don't enable LPIs without an ITS. */