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Date:   Wed, 20 Oct 2021 14:00:38 +0200
Message-Id: <CF47UZE6WXQ6.1MZDZ8OPGM0TW@taiga>
Subject: Re: Polling on an io_uring file descriptor
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From:   "Drew DeVault" <sir@cmpwn.com>
To:     "Pavel Begunkov" <asml.silence@gmail.com>,
        <io-uring@vger.kernel.org>
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On Wed Oct 20, 2021 at 1:58 PM CEST, Pavel Begunkov wrote:
> > One issue which remains is that attempting to use REGISTER_FILES on
> > io_uring A with io_uring B's file descriptor returns EBADF. I saw a
> > comment in the kernel source explaining this, but it's a bit contrived
> > and the error case is not documented.
>
> Surely should be updated if not mentioned

That, or the constraint removed? The reasoning is a bit obscure and I
suspect that this case could be made possible.