Re: [PATCH v1] mm/slub: add comment explaining intentional kobject handling in sysfs_slab_add

[Vlastimil Babka (SUSE)]

On 7/13/26 09:00, Hongling Zeng wrote:
> Add a comment to clarify why we don't call kobject_put() when
> kobject_init_and_add() fails in sysfs_slab_add().
> 
> Per commit 2420baa8e046 ("mm/slab: Allow cache creation to proceed
> even if sysfs registration fails"), sysfs failures are treated as
> non-fatal and the cache continues to be used. Calling kobject_put()
> would trigger slab_kmem_cache_release() which frees the entire
> cache structure, so we intentionally skip it.
> 
> Suggested-by: Harry Yoo <harry@xxxxxxxxxx>
> Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>

Thanks, added to slab/for-next

> ---
>  Change in v1:
>  -Correct the email
> ---
>  mm/slub.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index 9ec774dc7009..edc822d7d9ea 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -9690,6 +9690,11 @@ static int sysfs_slab_add(struct kmem_cache *s)
>  
>  	s->kobj.kset = kset;
>  	err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name);
> +	/*
> +	 * Intentionally skip kobject_put(). See commit 2420baa8e046
> +	 * ("mm/slab: Allow cache creation to proceed even if sysfs
> +	 * registration fails")
> +	 */
>  	if (err)
>  		goto out;
>