Re: [XEN PATCH 6/9] x86/io_apic: address violation of MISRA C:2012 Rule 10.1

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 6 Oct 2023, Nicola Vetrini wrote:
> The definition of IO_APIC_BASE contains a sum of an essentially enum
> value (FIX_IO_APIC_BASE_0) that is positive with an index that, in all
> instances, is unsigned, therefore the former is cast to unsigned, so that
> the operands are of the same essential type.
> 
> No functional change.

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
>  xen/arch/x86/include/asm/io_apic.h | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/xen/arch/x86/include/asm/io_apic.h 
> b/xen/arch/x86/include/asm/io_apic.h
> index a7e4c9e146de..a0fc50d601fe 100644
> --- a/xen/arch/x86/include/asm/io_apic.h
> +++ b/xen/arch/x86/include/asm/io_apic.h
> @@ -14,9 +14,10 @@
>   * Copyright (C) 1997, 1998, 1999, 2000 Ingo Molnar
>   */
>  
> -#define IO_APIC_BASE(idx)                                               \
> -    ((volatile uint32_t *)(__fix_to_virt(FIX_IO_APIC_BASE_0 + (idx))    \
> -                           + (mp_ioapics[idx].mpc_apicaddr & ~PAGE_MASK)))
> +#define IO_APIC_BASE(idx)                                     \
> +    ((volatile uint32_t *)                                    \
> +     (__fix_to_virt((unsigned int)FIX_IO_APIC_BASE_0 + (idx)) \
> +      + (mp_ioapics[idx].mpc_apicaddr & ~PAGE_MASK)))
>  
>  #define IO_APIC_ID(idx) (mp_ioapics[idx].mpc_apicid)
>  
> -- 
> 2.34.1
>