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Date:   Fri, 15 Jul 2022 10:54:39 -0700
From:   Roman Gushchin <roman.gushchin@linux.dev>
To:     Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
Cc:     axboe@kernel.dk, asml.silence@gmail.com, fam.zheng@bytedance.com,
        io-uring@vger.kernel.org, linux-kernel@vger.kernel.org,
        usama.arif@bytedance.com
Subject: Re: [PATCH] io_uring: Don't require reinitable percpu_ref
Message-ID: <YtGp318DAmjXrHh3@castle>
References: <8a9adb78-d9bb-a511-e4c1-c94cca392c9b@kernel.dk>
 <20220715174501.25216-1-mkoutny@suse.com>
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On Fri, Jul 15, 2022 at 07:45:01PM +0200, Michal Koutny wrote:
> The commit 8bb649ee1da3 ("io_uring: remove ring quiesce for
> io_uring_register") removed the worklow relying on reinit/resurrection
> of the percpu_ref, hence, initialization with that requested is a relic.
> 
> This is based on code review, this causes no real bug (and theoretically
> can't). Technically it's a revert of commit 214828962dea ("io_uring:
> initialize percpu refcounters using PERCU_REF_ALLOW_REINIT") but since
> the flag omission is now justified, I'm not making this a revert.
> 
> Fixes: 8bb649ee1da3 ("io_uring: remove ring quiesce for io_uring_register")
> Signed-off-by: Michal Koutn? <mkoutny@suse.com>

Acked-by: Roman Gushchin <roman.gushchin@linux.dev>

Thanks!