Re: [PATCH 5/5] xen/arm: address violations of MISRA C:2012 Rule 11.8

[Julien Grall <julien@xxxxxxx>]

Hi,

On 24/11/2023 17:29, Simone Ballarin wrote:
> From: Maria Celeste Cesario <maria.celeste.cesario@xxxxxxxxxxx>
>
> Add or amend casts to comply with Rule 11.8.
>
> The violations are resolved either:
> - by adding a missing const qualifier in the cast
> - by removing a cast to non-const on a const-qualified object
>
> No functional change.
>
> Signed-off-by: Maria Celeste Cesario  <maria.celeste.cesario@xxxxxxxxxxx>
> Signed-off-by: Simone Ballarin  <simone.ballarin@xxxxxxxxxxx>
> ---
>   xen/arch/arm/domain_build.c       | 2 +-
>   xen/arch/arm/include/asm/atomic.h | 2 +-
>   xen/arch/arm/include/asm/regs.h   | 2 +-
>   3 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index 2dd2926b41..c17214f738 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -2749,7 +2749,7 @@ static int __init handle_passthrough_prop(struct 
> kernel_info *kinfo,
>       if ( node == NULL )
>       {
>           printk(XENLOG_ERR "Couldn't find node %s in host_dt!\n",
> -               (char *)xen_path->data);
> +               xen_path->data);
I am a little bit puzzled why the cast was originally added here. 
Stefano, do you remember?
Also, this hunk will not apply on staging (the code has moved to 
dom0less-build.c). This will want a new version.
>           return -EINVAL;
>       }
>   
> diff --git a/xen/arch/arm/include/asm/atomic.h b/xen/arch/arm/include/asm/atomic.h
> index 64314d59b3..517216d2a8 100644
> --- a/xen/arch/arm/include/asm/atomic.h
> +++ b/xen/arch/arm/include/asm/atomic.h
> @@ -154,7 +154,7 @@ static always_inline void write_atomic_size(volatile void 
> *p,
>    */
>   static inline int atomic_read(const atomic_t *v)
>   {
> -    return *(volatile int *)&v->counter;
> +    return *(const volatile int *)&v->counter;
>   }
>   
>   static inline int _atomic_read(atomic_t v)
> diff --git a/xen/arch/arm/include/asm/regs.h b/xen/arch/arm/include/asm/regs.h
> index 8a0db95415..79050937f3 100644
> --- a/xen/arch/arm/include/asm/regs.h
> +++ b/xen/arch/arm/include/asm/regs.h
> @@ -48,7 +48,7 @@ static inline bool regs_mode_is_32bit(const struct 
> cpu_user_regs *regs)
>   
>   static inline bool guest_mode(const struct cpu_user_regs *r)
>   {
> -    unsigned long diff = (char *)guest_cpu_user_regs() - (char *)(r);
> +    unsigned long diff = (char *)guest_cpu_user_regs() - (const char *)(r);
NIT: I would take the opportunity to use 'const char*' for the first one 
as well.
>       /* Frame pointer must point into current CPU stack. */
>       ASSERT(diff < STACK_SIZE);
>       /* If not a guest frame, it must be a hypervisor frame. */
Cheers,

--
Julien Grall