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Howlett" , "Andrew Morton" , "Matthew Wilcox" , "Tamir Duberstein" , "Andreas Hindborg" , "Miguel Ojeda" , "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Trevor Gross" , , , To: "Alice Ryhl" From: "Danilo Krummrich" References: <20250715-align-min-allocator-v1-0-3e1b2a5516c0@google.com> <20250715-align-min-allocator-v1-1-3e1b2a5516c0@google.com> In-Reply-To: X-Rspamd-Queue-Id: ECB341C0007 X-Stat-Signature: bkdheb9skni39h4psbmk834mi4hdi3jh X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1752590349-224768 X-HE-Meta: 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 c34mKAFs E5tQlX8PqpzmY4/O4JjIJgdYhO2Vr9iQHqazPeAVinhMnqz6U5DidTQlMAvQOtTP7GpfiK6ElzCt0KjsXjtfrDw3MSKRSz1tLnmgajxjBtWGPQJD3+JJ2SvwmDeeCGWX/rMPnmv8Sjr5e15bvwGvRZDLhBemWkOiod91BEXz3AceVWy+lxrYrWIuxk1b8B3UCCrXroa6THVCyiRsur4eH4m7gtlHsNwhwZ/W9htakR/TJLrJHE1dhcH7Cri6OhRLkK4RDwC6J3/4pR9YV8va+PLAkJuVQI8gQIiaUdrAbldEAgk2+JFcukcB04JIXdoXm3VyJHnUxdMwrvQSurTAwtNc1mEHoQOIXkKLnh7RsxTgBLn1LXh71bHhIZw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue Jul 15, 2025 at 4:35 PM CEST, Alice Ryhl wrote: > On Tue, Jul 15, 2025 at 4:05=E2=80=AFPM Danilo Krummrich wrote: >> >> On Tue Jul 15, 2025 at 3:46 PM CEST, Alice Ryhl wrote: >> > diff --git a/rust/kernel/alloc.rs b/rust/kernel/alloc.rs >> > index a2c49e5494d334bfde67328464dafcdb31052947..c12753a5fb1c7423a40635= 53674b537a775c860e 100644 >> > --- a/rust/kernel/alloc.rs >> > +++ b/rust/kernel/alloc.rs >> > @@ -137,6 +137,14 @@ pub mod flags { >> > /// - Implementers must ensure that all trait functions abide by the = guarantees documented in the >> > /// `# Guarantees` sections. >> > pub unsafe trait Allocator { >> > + /// The minimum alignment satisfied by all allocations from this = allocator. >> > + /// >> > + /// # Guarantees >> > + /// >> > + /// Any pointer allocated by this allocator must be aligned to `M= IN_ALIGN` even if the >> > + /// requested layout has a smaller alignment. >> >> I'd say "is guaranteed to be aligned to" instead, "must be" reads like a >> requirement. > > Yes I agree that sounds better. > >> Speaking of which, I think this also needs to be expressed as a safety >> requirement of the Allocator trait itself, which the specific allocator >> implementations need to justify. > > The trait safety requirements already says that the implementation > must provide the guarantee listed on each item in the trait. Oh, indeed, that's fine then. :)