Re: [linux-next:master] [mm] b9b1861d4f: WARNING:possible_circular_locking_dependency_detected

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 9 Oct 2026 15:58:46 +0800 "Qi Zheng" <zhengqi.arch@bytedance.com> wrote:

> Could you please help test whether the following change makes the
> lockdep warning go away?
> 
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 5a9bcc7c66926..8ee767dccc1f6 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -5162,6 +5162,8 @@ static const struct dentry_operations 
> shmem_ci_dentry_ops = {
>   };
>   #endif
> 
> +static struct lock_class_key shmem_unused_huge_lock_key;
> +

This could be local to shmem_fill_super().

And inside #ifdef CONFIG_TRANSPARENT_HUGEPAGE somehow.

>   static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
>   {
>          struct shmem_options *ctx = fc->fs_private;
> @@ -5243,7 +5245,8 @@ static int shmem_fill_super(struct super_block 
> *sb, struct fs_context *fc)
>                  goto failed;
> 
>   #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> -       if (list_lru_init_memcg(&sbinfo->shrinklist, sb->s_shrink))
> +       if (list_lru_init_memcg_key(&sbinfo->shrinklist, sb->s_shrink,
> +                                   &shmem_unused_huge_lock_key))
>                  goto failed;
>   #endif
> 

Thanks, I'll await a formal (non-wordwrapped!) patch.