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References: <20220805154231.31257-13-ojeda@kernel.org> <Yu5Bex9zU6KJpcEm@yadro.com>
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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Sat, 6 Aug 2022 13:22:52 +0200
Message-ID: <CANiq72=3j2NM2kS8iw14G6MnGirb0=O6XQyCsY9vVgsZ1DfLaQ@mail.gmail.com>
Subject: Re: [PATCH v9 12/27] rust: add `kernel` crate
To:     Konstantin Shelekhin <k.shelekhin@yadro.com>
Cc:     ojeda@kernel.org, alex.gaynor@gmail.com, ark.email@gmail.com,
        bjorn3_gh@protonmail.com, bobo1239@web.de, bonifaido@gmail.com,
        boqun.feng@gmail.com, davidgow@google.com, dev@niklasmohrin.de,
        dsosnowski@dsosnowski.pl, foxhlchen@gmail.com, gary@garyguo.net,
        geofft@ldpreload.com, gregkh@linuxfoundation.org,
        jarkko@kernel.org, john.m.baublitz@gmail.com,
        leseulartichaut@gmail.com, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, m.falkowski@samsung.com,
        me@kloenk.de, milan@mdaverde.com, mjmouse9999@gmail.com,
        patches@lists.linux.dev, rust-for-linux@vger.kernel.org,
        thesven73@gmail.com, torvalds@linux-foundation.org,
        viktor@v-gar.de, wedsonaf@google.com,
        Andreas Hindborg <andreas.hindborg@wdc.com>
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On Sat, Aug 6, 2022 at 12:25 PM Konstantin Shelekhin
<k.shelekhin@yadro.com> wrote:
>
> I sense possible problems here. It's common for a kernel code to pass
> flags during memory allocations.

Yes, of course. We will support this, but how exactly it will look
like, to what extent upstream Rust's `alloc` could support our use
cases, etc. has been on discussion for a long time.

For instance, see https://github.com/Rust-for-Linux/linux/pull/815 for
a potential extension trait approach with no allocator carried on the
type that Andreas wrote after a discussion in the last informal call:

    let a = Box::try_new_atomic(101)?;

Cheers,
Miguel