linux-kernel - Re: [PATCH v12 1/8] mm: rust: add abstraction for struct mm

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: <87bjw1ekc6.fsf@kernel.org>
Date: Mon, 20 Jan 2025 13:33:13 +0100
From: Andreas Hindborg <a.hindborg@...nel.org>
To: "Alice Ryhl" <aliceryhl@...gle.com>
Cc: "Miguel Ojeda" <ojeda@...nel.org>,  "Matthew Wilcox"
 <willy@...radead.org>,  "Lorenzo Stoakes" <lorenzo.stoakes@...cle.com>,
  "Vlastimil Babka" <vbabka@...e.cz>,  "John Hubbard"
 <jhubbard@...dia.com>,  "Liam R. Howlett" <Liam.Howlett@...cle.com>,
  "Andrew Morton" <akpm@...ux-foundation.org>,  "Greg Kroah-Hartman"
 <gregkh@...uxfoundation.org>,  "Arnd Bergmann" <arnd@...db.de>,  "Jann
 Horn" <jannh@...gle.com>,  "Suren Baghdasaryan" <surenb@...gle.com>,
  "Alex Gaynor" <alex.gaynor@...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>,
  "Trevor Gross" <tmgross@...ch.edu>,  <linux-kernel@...r.kernel.org>,
  <linux-mm@...ck.org>,  <rust-for-linux@...r.kernel.org>
Subject: Re: [PATCH v12 1/8] mm: rust: add abstraction for struct mm_struct

"Alice Ryhl" <aliceryhl@...gle.com> writes:

> These abstractions allow you to reference a `struct mm_struct` using
> both mmgrab and mmget refcounts. This is done using two Rust types:
>
> * Mm - represents an mm_struct where you don't know anything about the
>   value of mm_users.
> * MmWithUser - represents an mm_struct where you know at compile time
>   that mm_users is non-zero.
>
> This allows us to encode in the type system whether a method requires
> that mm_users is non-zero or not. For instance, you can always call
> `mmget_not_zero` but you can only call `mmap_read_lock` when mm_users is
> non-zero.
>
> The struct is called Mm to keep consistency with the C side.
>
> The ability to obtain `current->mm` is added later in this series.
>
> Acked-by: Lorenzo Stoakes <lorenzo.stoakes@...cle.com> (for mm bits)
> Signed-off-by: Alice Ryhl <aliceryhl@...gle.com>

Reviewed-by: Andreas Hindborg <a.hindborg@...nel.org>

Best regards,
Andreas Hindborg