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Date:   Thu, 4 May 2023 11:36:01 -0700
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Subject: Re: [RFC PATCH 00/11] Rust null block driver
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To:     Andreas Hindborg <nmi@metaspace.dk>
Cc:     Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        Keith Busch <kbusch@kernel.org>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Hannes Reinecke <hare@suse.de>,
        lsf-pc@lists.linux-foundation.org, rust-for-linux@vger.kernel.org,
        linux-block@vger.kernel.org, Matthew Wilcox <willy@infradead.org>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?UTF-8?Q?Bj=c3=b6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Benno Lossin <benno.lossin@proton.me>,
        open list <linux-kernel@vger.kernel.org>, gost.dev@samsung.com
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 <da7b815d-3da8-38e5-9b25-b9cfb6878293@acm.org> <87jzxot0jk.fsf@metaspace.dk>
From:   Bart Van Assche <bvanassche@acm.org>
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On 5/4/23 11:15, Andreas Hindborg wrote:
> If it is still unclear to you why this effort was started, please do let
> me know and I shall try to clarify further :)

It seems like I was too polite in my previous email. What I meant is that
rewriting code is useful if it provides a clear advantage to the users of
a driver. For null_blk, the users are kernel developers. The code that has
been posted is the start of a rewrite of the null_blk driver. The benefits
of this rewrite (making low-level memory errors less likely) do not outweigh
the risks that this effort will introduce functional or performance regressions.

Bart.