Re: [PATCH] mm/mseal: use min/max in mseal_apply

Re: [PATCH] mm/mseal: use min/max in mseal_apply

[David Laight]

On Sun, 3 May 2026 21:58:57 +0100
Pedro Falcato <pfalcato@suse.de> wrote:

> On Sun, May 03, 2026 at 01:59:16PM +0200, Thorsten Blum wrote:
> > Use the type-checked min()/max() macros instead of MIN()/MAX(), which
> > are supposed to be used "for obvious constants only".  
> 
> Gotta love these macros... FYI this isn't the only wrong usage in the kernel.

I failed to persuade Linus to include a test for __builtin_constant_p((a)|(b)) :-)

-- David

> 
> > 
> > Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>  
> 
> Reviewed-by: Pedro Falcato <pfalcato@suse.de>
> 

Re: [PATCH] mm/mseal: use min/max in mseal_apply

[Lorenzo Stoakes]

On Sun, May 03, 2026 at 01:59:16PM +0200, Thorsten Blum wrote:
> Use the type-checked min()/max() macros instead of MIN()/MAX(), which
> are supposed to be used "for obvious constants only".
>
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

Oops my bad :)

LGTM, so:

Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>

> ---
>  mm/mseal.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/mm/mseal.c b/mm/mseal.c
> index e2093ae3d25c..9781647483d1 100644
> --- a/mm/mseal.c
> +++ b/mm/mseal.c
> @@ -8,6 +8,7 @@
>   */
>
>  #include <linux/mempolicy.h>
> +#include <linux/minmax.h>
>  #include <linux/mman.h>
>  #include <linux/mm.h>
>  #include <linux/mm_inline.h>
> @@ -65,8 +66,8 @@ static int mseal_apply(struct mm_struct *mm,
>  		prev = vma;
>
>  	for_each_vma_range(vmi, vma, end) {
> -		const unsigned long curr_start = MAX(vma->vm_start, start);
> -		const unsigned long curr_end = MIN(vma->vm_end, end);
> +		const unsigned long curr_start = max(vma->vm_start, start);
> +		const unsigned long curr_end = min(vma->vm_end, end);
>
>  		if (!vma_test(vma, VMA_SEALED_BIT)) {
>  			vma_flags_t vma_flags = vma->flags;

Re: [PATCH] mm/mseal: use min/max in mseal_apply

[David Hildenbrand (Arm)]

On 5/3/26 13:59, Thorsten Blum wrote:
> Use the type-checked min()/max() macros instead of MIN()/MAX(), which
> are supposed to be used "for obvious constants only".
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---

Acked-by: David Hildenbrand (Arm) <david@kernel.org>

-- 
Cheers,

David

Re: [PATCH] mm/mseal: use min/max in mseal_apply

[SeongJae Park]

On Sun,  3 May 2026 13:59:16 +0200 Thorsten Blum <thorsten.blum@linux.dev> wrote:

> Use the type-checked min()/max() macros instead of MIN()/MAX(), which
> are supposed to be used "for obvious constants only".
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

Reviewed-by: SeongJae Park <sj@kernel.org>


Thanks,
SJ

[...]