Re: [PATCH 08/12] Arm/GIC: add noreturn in a few more places

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 28 Aug 2026, Jan Beulich wrote:
> LPI related functions having just BUG() in them are disliked by Misra /
> Eclair, as long as they don't also have a noreturn attribute.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
> >From its description "Unreachability caused by calls to the following
> functions or macros is deliberate and there is no risk of code being
> unexpectedly left out." I would have expected the respective entry in
> deviations.ecl to cover all of these cases, but clearly that isn't the
> case.
> 
> Of course having noreturn on functions returning non-void is somewhat odd.
> 
> --- a/xen/arch/arm/gic-v2.c
> +++ b/xen/arch/arm/gic-v2.c
> @@ -1315,7 +1315,7 @@ static int __init gicv2_init(void)
>      return 0;
>  }
>  
> -static void gicv2_do_LPI(unsigned int lpi)
> +static void noreturn gicv2_do_LPI(unsigned int lpi)
>  {
>      /* No LPIs in a GICv2 */
>      BUG();
> --- a/xen/arch/arm/include/asm/gic_v3_its.h
> +++ b/xen/arch/arm/include/asm/gic_v3_its.h
> @@ -229,7 +229,7 @@ static inline unsigned int vgic_v3_its_c
>      return 0;
>  }
>  
> -static inline void gicv3_do_LPI(unsigned int lpi)
> +static inline void noreturn gicv3_do_LPI(unsigned int lpi)
>  {
>      /* We don't enable LPIs without an ITS. */
>      BUG();
> --- a/xen/arch/arm/vgic-v2.c
> +++ b/xen/arch/arm/vgic-v2.c
> @@ -718,14 +718,15 @@ static void vgic_v2_domain_free(struct d
>      /* Nothing to be cleanup for this driver */
>  }
>  
> -static struct pending_irq *vgic_v2_lpi_to_pending(struct domain *d,
> -                                                  unsigned int vlpi)
> +static struct pending_irq *noreturn vgic_v2_lpi_to_pending(struct domain *d,
> +                                                           unsigned int vlpi)
>  {
>      /* Dummy function, no LPIs on a VGICv2. */
>      BUG();
>  }
>  
> -static int vgic_v2_lpi_get_priority(struct domain *d, unsigned int vlpi)
> +static int noreturn vgic_v2_lpi_get_priority(struct domain *d,
> +                                             unsigned int vlpi)
>  {
>      /* Dummy function, no LPIs on a VGICv2. */
>      BUG();
>