[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20240514102757.b7034966a58e6cf44d75dc7d@linux-foundation.org>
Date: Tue, 14 May 2024 10:27:57 -0700
From: Andrew Morton <akpm@...ux-foundation.org>
To: Alice Ryhl <aliceryhl@...gle.com>
Cc: Miguel Ojeda <ojeda@...nel.org>, Matthew Wilcox <willy@...radead.org>,
Al Viro <viro@...iv.linux.org.uk>, Kees Cook <keescook@...omium.org>, Alex
Gaynor <alex.gaynor@...il.com>, Wedson Almeida Filho <wedsonaf@...il.com>,
Boqun Feng <boqun.feng@...il.com>, Gary Guo <gary@...yguo.net>,
"Björn Roy Baron" <bjorn3_gh@...tonmail.com>, Benno
Lossin <benno.lossin@...ton.me>, Andreas Hindborg <a.hindborg@...sung.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>, "Arve Hjønnevåg" <arve@...roid.com>, Todd Kjos
<tkjos@...roid.com>, Martijn Coenen <maco@...roid.com>, Joel Fernandes
<joel@...lfernandes.org>, Carlos Llamas <cmllamas@...gle.com>, Suren
Baghdasaryan <surenb@...gle.com>, Arnd Bergmann <arnd@...db.de>, Trevor
Gross <tmgross@...ch.edu>, linux-mm@...ck.org,
linux-kernel@...r.kernel.org, rust-for-linux@...r.kernel.org, Christian
Brauner <brauner@...nel.org>
Subject: Re: [PATCH v6 2/4] uaccess: always export _copy_[from|to]_user with
CONFIG_RUST
On Thu, 18 Apr 2024 08:59:18 +0000 Alice Ryhl <aliceryhl@...gle.com> wrote:
> From: Arnd Bergmann <arnd@...db.de>
>
> Rust code needs to be able to access _copy_from_user and _copy_to_user
> so that it can skip the check_copy_size check in cases where the length
> is known at compile-time, mirroring the logic for when C code will skip
> check_copy_size. To do this, we ensure that exported versions of these
> methods are available when CONFIG_RUST is enabled.
>
> Alice has verified that this patch passes the CONFIG_TEST_USER_COPY test
> on x86 using the Android cuttlefish emulator.
>
> ...
>
> -#ifdef INLINE_COPY_TO_USER
> static inline __must_check unsigned long
> -_copy_to_user(void __user *to, const void *from, unsigned long n)
> +_inline_copy_to_user(void __user *to, const void *from, unsigned long n)
> {
I think it would be helpful to have some comments in here describing
why we're doing this _inline_* thing. What problem is it avoiding?
Powered by blists - more mailing lists