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

["Qi Zheng" <zhengqi.arch@bytedance.com>]

Hi Andrew,

On 10/11/26 7:16 AM, Andrew Morton wrote:
> 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.

Got it. Will do.

> 
>>    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.

OK, I'll send a formal fix patch soon.

Thanks,
Qi