From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17077C83F17 for ; Tue, 15 Jul 2025 16:01:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AF9578D0002; Tue, 15 Jul 2025 12:01:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AD1328D0001; Tue, 15 Jul 2025 12:01:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A0E648D0002; Tue, 15 Jul 2025 12:01:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 904E38D0001 for ; Tue, 15 Jul 2025 12:01:53 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 06EA88053A for ; Tue, 15 Jul 2025 16:01:52 +0000 (UTC) X-FDA: 83666964906.20.5A8FAD6 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf17.hostedemail.com (Postfix) with ESMTP id 2D94D4000C for ; Tue, 15 Jul 2025 16:01:50 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XzCmk5Mn; spf=pass (imf17.hostedemail.com: domain of lossin@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=lossin@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1752595311; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=zxtMk56xP8hs4SSusFl+W7T6Y5lDf4DfYBF4qLSqGl0=; b=IR355c/UrfNJAKBhpCwbbuXW5SaLXDyxR5xD9PfNYgUUs6djQMkqbbyTJABa1+lHRkn6Nt ArkiaNN4IFzdHnCwRV5nFO4F1QMsWZPju+gi6HuacuwqumvjQ+sHsy+Vl1H+1aUC2l7NNi ieWJm0daMNBHkuzOmhN+cGPKW7dobUI= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XzCmk5Mn; spf=pass (imf17.hostedemail.com: domain of lossin@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=lossin@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1752595311; a=rsa-sha256; cv=none; b=ce7NCJARknrhr1PMIl4cN/QsBC8v4pgADs4rb8JgRqf1OPXWm3G+oFeVsdfM13tCDkqEm9 A0w9bau5eoyBU+7e+3TPUJ0n+vGWp1EBTLtsKO3EWbMHnqB68cPPV39BFH/WKR/s9jlcNH OOaZSNWNV9rCySUePXS8kdTrPRbBNJ8= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 0070745487; Tue, 15 Jul 2025 16:01:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C570BC4CEE3; Tue, 15 Jul 2025 16:01:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752595309; bh=DdqdkgiI5juyrgRHxtfAw0lfeAZe216KfAyarFrwOc0=; h=Date:Cc:Subject:From:To:References:In-Reply-To:From; b=XzCmk5MnGIZ36EIsWFAYiW1J+lxwjGT0Oqt/W07MSBWmYxII9Qja8BCjuWncMg72t EvoMQFMWgZ+IlGN1jdFKE1JrU8kdHDz9tZunqOT4eVCq26bMiiLHQOKeNt2vsny+8A zyY1JRdhNAlx/4Gyk5yRI70JUSOman3CCJXJYs+7nHBClOwgw1Dib4SrfcKuows8iT xa/mjLfqY04mA7aCw+WfjaALm8TrmVZOsqNFES8lxzGrFQ1ijWjKlFaSKbYRAbqqEw +MwpOF99HDtU1lDdR6+Lq6KYrn1f4ezUtuKMS7TFFplPx/DyeBKvzfbRlkOrtf9U1m Uf/JceIi/JzPA== Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Tue, 15 Jul 2025 18:01:44 +0200 Message-Id: Cc: "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Trevor Gross" , , , Subject: Re: [PATCH 1/2] rust: alloc: specify the minimum alignment of each allocator From: "Benno Lossin" To: "Alice Ryhl" , "Lorenzo Stoakes" , "Liam R. Howlett" , "Andrew Morton" , "Danilo Krummrich" , "Matthew Wilcox" , "Tamir Duberstein" , "Andreas Hindborg" , "Miguel Ojeda" X-Mailer: aerc 0.20.1 References: <20250715-align-min-allocator-v1-0-3e1b2a5516c0@google.com> <20250715-align-min-allocator-v1-1-3e1b2a5516c0@google.com> In-Reply-To: <20250715-align-min-allocator-v1-1-3e1b2a5516c0@google.com> X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 2D94D4000C X-Stat-Signature: 8noy1croutcxog65jys6pfi8r1kzj3w9 X-HE-Tag: 1752595310-651489 X-HE-Meta: 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 gCBPJ5K9 BFDclmRJbmVY/EyvK4yEebm5rGO67d4BxZcYC6ErZwa08GUPSrJKpRT1tHTtfCtxYdMYX1bORVjW08WEwkBMXO300uS0BJlZBgZvKXDSW6Ddc6N9+q3DdoNiedwEJ970o76w8qrN1ULGSlk88XXN2dBF956HObEvVT6C15Oeb88329fa4ysGxnhZzcpAVCPuqPcpwFRp7KojN+PkzOs9XHJYDFBePu/p+Op7oz/MKYKyBMuKDu18aK9XRA6y2YkbY06dySaxRrBGpM9QAGFYJ273nhiaYLslMp1kIqDp+eotIQwN+NCgYz83yQ35VlnGYGdXqon+zD71Ji/DRq90qx3q5fHmXXjxKhaGe 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: > The kernel's allocators sometimes provide a higher alignment than the > end-user requested, so add a new constant on the Allocator trait to let > the allocator specify what its minimum guaranteed alignment is. > > This allows the ForeignOwnable trait to provide a more accurate value of > FOREIGN_ALIGN when using a pointer type such as Box, which will be > useful with certain collections such as XArray that store its own data > in the low bits of pointers. > > Signed-off-by: Alice Ryhl With the wording changed according to Danilo's suggestion: Reviewed-by: Benno Lossin --- Cheers, Benno > --- > rust/kernel/alloc.rs | 8 ++++++++ > rust/kernel/alloc/allocator.rs | 8 ++++++++ > 2 files changed, 16 insertions(+)