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Date:   Fri, 1 May 2020 04:58:20 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] pipe: read/write_iter() handler should check for
 IOCB_NOWAIT
Message-ID: <20200501035820.GH23230@ZenIV.linux.org.uk>
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On Thu, Apr 30, 2020 at 10:24:46AM -0600, Jens Axboe wrote:
> Pipe read/write only checks for the file O_NONBLOCK flag, but we should
> also check for IOCB_NOWAIT for whether or not we should handle this read
> or write in a non-blocking fashion. If we don't, then we will block on
> data or space for iocbs that explicitly asked for non-blocking
> operation. This messes up callers that explicitly ask for non-blocking
> operations.

Why does io_uring allow setting IOCB_NOWAIT without FMODE_NOWAIT, anyway?