linux-kernel - Re: [PATCH v14 2/3] rust: support formatting of foreign types

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <DC09SG6IXEOG.3Q8DMJF5E7QBO@kernel.org>
Date: Tue, 12 Aug 2025 09:27:50 +0200
From: "Benno Lossin" <lossin@...nel.org>
To: "Tamir Duberstein" <tamird@...il.com>, "Miguel Ojeda"
 <ojeda@...nel.org>, "Alex Gaynor" <alex.gaynor@...il.com>, "Boqun Feng"
 <boqun.feng@...il.com>, "Gary Guo" <gary@...yguo.net>,
 Björn Roy Baron <bjorn3_gh@...tonmail.com>, "Andreas
 Hindborg" <a.hindborg@...nel.org>, "Alice Ryhl" <aliceryhl@...gle.com>,
 "Trevor Gross" <tmgross@...ch.edu>, "Danilo Krummrich" <dakr@...nel.org>,
 "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>, "Rafael J. Wysocki"
 <rafael@...nel.org>, "Luis Chamberlain" <mcgrof@...nel.org>, "Russ Weight"
 <russ.weight@...ux.dev>, "Peter Zijlstra" <peterz@...radead.org>, "Ingo
 Molnar" <mingo@...hat.com>, "Will Deacon" <will@...nel.org>, "Waiman Long"
 <longman@...hat.com>, "Nathan Chancellor" <nathan@...nel.org>, "Nick
 Desaulniers" <nick.desaulniers+lkml@...il.com>, "Bill Wendling"
 <morbo@...gle.com>, "Justin Stitt" <justinstitt@...gle.com>, "Christian
 Brauner" <brauner@...nel.org>
Cc: <rust-for-linux@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
 <llvm@...ts.linux.dev>
Subject: Re: [PATCH v14 2/3] rust: support formatting of foreign types

On Thu Jul 10, 2025 at 4:53 PM CEST, Tamir Duberstein wrote:
> Introduce a `fmt!` macro which wraps all arguments in
> `kernel::fmt::Adapter` and a `kernel::fmt::Display` trait. This enables
> formatting of foreign types (like `core::ffi::CStr`) that do not
> implement `core::fmt::Display` due to concerns around lossy conversions
> which do not apply in the kernel.
>
> Suggested-by: Alice Ryhl <aliceryhl@...gle.com>
> Link: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/Custom.20formatting/with/516476467
> Acked-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> Reviewed-by: Alice Ryhl <aliceryhl@...gle.com>
> Signed-off-by: Tamir Duberstein <tamird@...il.com>

I'm not 100% sure we need to always use `first_span`, but it's probably
fine.

Reviewed-by: Benno Lossin <lossin@...nel.org>

---
Cheers,
Benno

> ---
>  rust/kernel/fmt.rs     | 87 +++++++++++++++++++++++++++++++++++++++++++++-
>  rust/kernel/prelude.rs |  3 +-
>  rust/macros/fmt.rs     | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  rust/macros/lib.rs     | 19 ++++++++++
>  rust/macros/quote.rs   |  7 ++++
>  5 files changed, 207 insertions(+), 3 deletions(-)