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Subject: Re: [PATCH] io_uring: unregister eventfd while holding lock when
 freeing ring ctx
To:     Usama Arif <usama.arif@bytedance.com>, io-uring@vger.kernel.org,
        asml.silence@gmail.com, linux-kernel@vger.kernel.org
Cc:     fam.zheng@bytedance.com, lkp@lists.01.org, lkp@intel.com,
        kernel test robot <oliver.sang@intel.com>
References: <20220207105040.2662467-1-usama.arif@bytedance.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <696e49fe-3d2e-da6c-2fc6-5d69bc7a60f9@kernel.dk>
Date:   Mon, 7 Feb 2022 06:46:46 -0700
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On 2/7/22 3:50 AM, Usama Arif wrote:
> This is because ctx->io_ev_fd is rcu_dereference_protected using
> ctx->uring_lock in io_eventfd_unregister. Not locking the function
> resulted in suspicious RCU usage reported by kernel test robot.

I'll fold this in with the change, thanks.

-- 
Jens Axboe