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	Tue, 17 Feb 2026 05:38:48 +0000
Date: Mon, 16 Feb 2026 21:38:48 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Joanne Koong <joannelkoong@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	Pavel Begunkov <asml.silence@gmail.com>, axboe@kernel.dk,
	io-uring@vger.kernel.org, csander@purestorage.com, krisman@suse.de,
	bernd@bsbernd.com, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v1 03/11] io_uring/kbuf: add support for kernel-managed
 buffer rings
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On Fri, Feb 13, 2026 at 11:14:03AM -0800, Joanne Koong wrote:
> I think we have the exact same use case, except your buffers need to
> be read-only. I think your use case benefits from the same memory wins
> we'll get with incremental buffer consumption, which is the primary
> reason fuse is using a bufring instead of fixed buffers.

Yeah.

> I think you can and it'll be very easy to do so. All that would be
> needed is to pass in a read-only flag from the userspace side when it
> registers the bufring, and then when userspace makes the mmap call to
> the bufring, the kernel checks if that read-only flag is set on the
> bufring and if so returns a read-only mapping. 

Yes, tat's what I though.  But Pavel seems to disagree?