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Date: Mon, 15 Dec 2025 15:38:15 +0100
From: Christoph Hellwig <hch@lst.de>
To: Yongpeng Yang <yangyongpeng.storage@gmail.com>
Cc: Damien Le Moal <dlemoal@kernel.org>, Christoph Hellwig <hch@lst.de>,
	Jens Axboe <axboe@kernel.dk>, Ming Lei <ming.lei@redhat.com>,
	linux-block@vger.kernel.org,
	Yongpeng Yang <yangyongpeng@xiaomi.com>,
	Yongpeng Yang <yangyongpeng.storage@outlook.com>
Subject: Re: [PATCH v3 1/2] loop: use READ_ONCE() to read lo->lo_state
 without locking
Message-ID: <20251215143815.GA30633@lst.de>
References: <20251215094522.1493061-2-yangyongpeng.storage@gmail.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Mon, Dec 15, 2025 at 05:45:22PM +0800, Yongpeng Yang wrote:
>  	idr_for_each_entry(&loop_index_idr, lo, id) {
>  		/* Hitting a race results in creating a new loop device which is harmless. */
> -		if (lo->idr_visible && data_race(lo->lo_state) == Lo_unbound)
> +		if (lo->idr_visible && data_race(READ_ONCE(lo->lo_state)) == Lo_unbound)

Please avoid the overly long line here (and maybe fix the one above).