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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" References: <20250715-align-min-allocator-v1-0-3e1b2a5516c0@google.com> <20250715-align-min-allocator-v1-2-3e1b2a5516c0@google.com> In-Reply-To: <20250715-align-min-allocator-v1-2-3e1b2a5516c0@google.com> X-Rspamd-Queue-Id: 3107B100009 X-Rspam-User: X-Rspamd-Server: rspam09 X-Stat-Signature: ddxkca1ygpb7iyf38sbipngbwym4fxt8 X-HE-Tag: 1752589199-194123 X-HE-Meta: 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 wwQF0gw0 jby/0MpIWbNyBpLjd4ad0g3MDW9J2LMGz+Oi/G4mSDStnWs4j6ukS9C0NuBCYTM0J/Ppqopx/599xnKFdX5LASMgl0H/iPPApsWcWtYY5UBhQms4MMgQgNiNFsVwfTQdl4poi0motUKS9kni+svkPz/JHKEetOdcRk/rCeBQbmL5UTNoFSowsu5MoRkWq3tbeyzWLqZgaKlAKS7C5mKNQHMRId7nM9DdxnT/NwtRDOwL4OjWGIPjCmjICDLyP/U5kmoyG5ewb7HQG9wkmML3lSHt2qbMuevxjK0I+WiVw8B9P11EenRPg3eoFZXPqthMWmxbbyDnFUi2p+SbC+rfoMbq1gEFwpzVUgLxPzDYdX2ro5UM= 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 3:46 PM CEST, Alice Ryhl wrote: > diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs > index bffe72f44cb33a265018e67d92d9f0abe82f8e22..fd3f1e0b9c3b3437fb50d8f1b= 28c92bc7cefd565 100644 > --- a/rust/kernel/alloc/kbox.rs > +++ b/rust/kernel/alloc/kbox.rs > @@ -400,12 +400,19 @@ fn try_init(init: impl Init, flags: Flags)= -> Result > } > =20 > // SAFETY: The pointer returned by `into_foreign` comes from a well alig= ned > -// pointer to `T`. > +// pointer to `T` allocated by `A`. > unsafe impl ForeignOwnable for Box > where > A: Allocator, > { > - const FOREIGN_ALIGN: usize =3D core::mem::align_of::(); > + const FOREIGN_ALIGN: usize =3D { > + let mut align =3D core::mem::align_of::(); > + if align < A::MIN_ALIGN { > + align =3D A::MIN_ALIGN; > + } > + align > + }; Pretty unfortunate that core::cmp::max() can't be used from const context. = :( What do you think about const FOREIGN_ALIGN: usize =3D if core::mem::align_of::() < A::MIN_ALIGN { A::MIN_ALIGN } else { core::mem::align_of::() }; instead? I think that reads a bit better.