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Date: Wed, 2 Sep 2026 12:32:02 +0200
From: Christoph Hellwig <hch@lst.de>
To: Runyu Xiao <runyu.xiao@seu.edu.cn>
Cc: Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Chaitanya Kulkarni <kch@nvidia.com>,
	Keith Busch <kbusch@kernel.org>,
	Logan Gunthorpe <logang@deltatee.com>,
	linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
	stable@vger.kernel.org, Jianhao Xu <jianhao.xu@seu.edu.cn>
Subject: Re: [PATCH v2 2/3] nvmet: avoid recursive configfs open for
 file-backed namespaces
Message-ID: <20260902103202.GB8095@lst.de>
References: <20260817143714.1344255-1-runyu.xiao@seu.edu.cn> <20260819155228.84938-1-runyu.xiao@seu.edu.cn> <20260819155228.84938-3-runyu.xiao@seu.edu.cn>
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User-Agent: Mutt/1.5.17 (2007-11-01)

> +	ret = kern_path(ns->device_path, LOOKUP_FOLLOW, &path);
> +	if (ret) {
> +		pr_err("failed to open file %s: (%d)\n",
> +		       ns->device_path, ret);
> +		return ret;
> +	}
> +
> +	if (configfs_path_is_configfs(&path)) {
> +		pr_err("configfs paths cannot back namespace %s\n",
> +		       ns->device_path);
> +		path_put(&path);
> +		return -EINVAL;
> +	}
> +
> +	ns->file = dentry_open(&path, flags, current_cred());

This section of code really should have a helper in configfs.  And should
also be used in other callers like the SCSI target patches you also sent
out.