Message-ID: <fcb92d78-fc5a-8f51-8a1b-75fd878cf8a1@linux.alibaba.com>
Date:   Thu, 9 Feb 2023 14:06:00 +0800
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Subject: Re: [PATCH v2 3/4] erofs: relinquish volume with mutex held
To:     Jingbo Xu <jefflexu@linux.alibaba.com>, xiang@kernel.org,
        chao@kernel.org, linux-erofs@lists.ozlabs.org,
        zhujia.zj@bytedance.com
Cc:     huyue2@coolpad.com, linux-kernel@vger.kernel.org
References: <20230209051838.33297-1-jefflexu@linux.alibaba.com>
 <20230209051838.33297-4-jefflexu@linux.alibaba.com>
From:   Gao Xiang <hsiangkao@linux.alibaba.com>
In-Reply-To: <20230209051838.33297-4-jefflexu@linux.alibaba.com>
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On 2023/2/9 13:18, Jingbo Xu wrote:
> Relinquish fscache volume with mutex held.  Otherwise if a new domain is
> registered when the old domain with the same name gets removed from the
> list but not relinquished yet, fscache may complain the collision.
> 
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>

Do we need to backport this to old kernels?
IOWs, whether "Fixes:" tag is needed?

Thanks,
Gao Xiang

> ---
>   fs/erofs/fscache.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
> index 2f5930e177cc..a6f030966147 100644
> --- a/fs/erofs/fscache.c
> +++ b/fs/erofs/fscache.c
> @@ -328,8 +328,8 @@ static void erofs_fscache_domain_put(struct erofs_domain *domain)
>   			kern_unmount(erofs_pseudo_mnt);
>   			erofs_pseudo_mnt = NULL;
>   		}
> -		mutex_unlock(&erofs_domain_list_lock);
>   		fscache_relinquish_volume(domain->volume, NULL, false);
> +		mutex_unlock(&erofs_domain_list_lock);
>   		kfree(domain->domain_id);
>   		kfree(domain);
>   		return;