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Date: Tue, 10 Mar 2026 10:14:43 -0600
From: Keith Busch <kbusch@kernel.org>
To: Daniele Di Proietto <daniele.di.proietto@gmail.com>
Cc: io-uring@vger.kernel.org, Jens Axboe <axboe@kernel.dk>
Subject: Re: [PATCH] io_uring: Add IORING_OP_DUP
Message-ID: <abBDc589oZdfR_aD@kbusch-mbp>
References: <20260310154933.2500971-1-daniele.di.proietto@gmail.com>
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In-Reply-To: <20260310154933.2500971-1-daniele.di.proietto@gmail.com>

On Tue, Mar 10, 2026 at 03:49:33PM +0000, Daniele Di Proietto wrote:
> +int io_dup(struct io_kiocb *req, unsigned int issue_flags)
> +{
> +	struct io_dup *id;
> +	int ret;
> +
> +	id = io_kiocb_to_cmd(req, struct io_dup);
> +	ret = replace_fd(id->new_fd, id->file, id->o_flags);

It looks like there are a few conditions where replace_fd may block,
so it may be a problem to call it from the uring enter context since it
will block progress through the sq ring for subsequent commands.