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From: Jens Axboe <axboe@kernel.dk>
To: linke li <lilinke99@qq.com>
Cc: xujianhao01@gmail.com, Andrew Morton <akpm@linux-foundation.org>, 
 linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
In-Reply-To: <tencent_0B517C25E519D3D002194E8445E86C04AD0A@qq.com>
References: <tencent_0B517C25E519D3D002194E8445E86C04AD0A@qq.com>
Subject: Re: [PATCH] sbitmap: use READ_ONCE to access map->word
Message-Id: <171413885096.211722.564458609126458139.b4-ty@kernel.dk>
Date: Fri, 26 Apr 2024 07:40:50 -0600
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On Fri, 26 Apr 2024 18:34:44 +0800, linke li wrote:
> In __sbitmap_queue_get_batch(), map->word is read several times, and
> update atomically using atomic_long_try_cmpxchg(). But the first two read
> of map->word is not protected.
> 
> This patch moves the statement val = READ_ONCE(map->word) forward,
> eliminating unprotected accesses to map->word within the function.
> It is aimed at reducing the number of benign races reported by KCSAN in
> order to focus future debugging effort on harmful races.
> 
> [...]

Applied, thanks!

[1/1] sbitmap: use READ_ONCE to access map->word
      commit: 6ad0d7e0f4b68f87a98ea2b239123b7d865df86b

Best regards,
-- 
Jens Axboe