Re: [PATCH v2 2/3] mm: change type of state in struct memory_block

[Randy Dunlap <rdunlap@infradead.org>]

On 10/29/25 12:56 PM, Israel Batista wrote:
> The state of a memory block should be restricted to values specified
> in the documentation of the memory hotplug API. However, since the
> state field in the memory_block struct was defined as an unsigned
> long, this restriction was not enforced at compile time.
> 
> With the introduction of the enum memory_block_state, it is now possible
> to incorporate the desired semantics in the field declaration and
> enforce these restrictions at compile time.
> 
> Signed-off-by: Israel Batista <linux@israelbatista.dev.br>
> ---
>  drivers/base/memory.c  | 2 +-
>  include/linux/memory.h | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> index 6d84a02cfa5d..3d17dd774947 100644
> --- a/drivers/base/memory.c
> +++ b/drivers/base/memory.c
> @@ -198,7 +198,7 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
>  		break;
>  	default:
>  		WARN_ON(1);
> -		return sysfs_emit(buf, "ERROR-UNKNOWN-%ld\n", mem->state);
> +		return sysfs_emit(buf, "ERROR-UNKNOWN-%d\n", mem->state);
>  	}
>  
>  	return sysfs_emit(buf, "%s\n", output);
> diff --git a/include/linux/memory.h b/include/linux/memory.h
> index f4e358477c6a..36d733283329 100644
> --- a/include/linux/memory.h
> +++ b/include/linux/memory.h
> @@ -78,7 +78,7 @@ enum memory_block_state {
>  
>  struct memory_block {
>  	unsigned long start_section_nr;
> -	unsigned long state;		/* serialized by the dev->lock */
> +	enum memory_block_state state; /* serialized by the dev->lock */

Use a tab after the ';' please, instead of a space, to align the comments.

>  	int online_type;		/* for passing data to online routine */
>  	int nid;			/* NID for this memory block */
>  	/*

-- 
~Randy