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 47F3FEB64D8 for ; Wed, 14 Jun 2023 16:35:00 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B47F76B0075; Wed, 14 Jun 2023 12:34:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AF6C98E0001; Wed, 14 Jun 2023 12:34:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 998B36B007E; Wed, 14 Jun 2023 12:34:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 879886B0075 for ; Wed, 14 Jun 2023 12:34:59 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 19972AFEAF for ; Wed, 14 Jun 2023 16:34:59 +0000 (UTC) X-FDA: 80901902718.13.824F7A6 Received: from mail-oa1-f53.google.com (mail-oa1-f53.google.com [209.85.160.53]) by imf30.hostedemail.com (Postfix) with ESMTP id BF32080017 for ; Wed, 14 Jun 2023 16:34:55 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=gmail.com header.s=20221208 header.b=J0jSJqDu; spf=pass (imf30.hostedemail.com: domain of yakoyoku@gmail.com designates 209.85.160.53 as permitted sender) smtp.mailfrom=yakoyoku@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1686760495; 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=P02UcLI2//J8LvUgRFLkUqu+ureKnlEB4HrY9Uc3j4k=; b=XZ+kgTKKTVU7Bfmevvfa9bhkBKmYezZcPzcoO6ravmzqxApYl4Z5/rQAp1DNHpULPVkGEG tjCiQbgZcNPgU5kDI1K2QHrvene8JxTSEEc1P/ChuKY2up6kczwaGuQZ6tMT1O5du30ngw TdRKrgZ1ciUusqGq/e2EoT5hkQYGYr8= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1686760495; a=rsa-sha256; cv=none; b=ZF23PuXh1zW6BrTHl21A1W68rDVnqTVhRr3Vnx0WjRTWIZBwfBlrV4YsDd3Cyd2ZyXNuYj RysiQQ0s7lhQo/MrCgGSUcc/BNvMQdx28WEvVAlxv9cDSL7oGjYP/Rs1boqw86e7M6BdnQ sTHFOHnq9NtcyJrJdv8NMUMmwG+BBb4= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=gmail.com header.s=20221208 header.b=J0jSJqDu; spf=pass (imf30.hostedemail.com: domain of yakoyoku@gmail.com designates 209.85.160.53 as permitted sender) smtp.mailfrom=yakoyoku@gmail.com; dmarc=pass (policy=none) header.from=gmail.com Received: by mail-oa1-f53.google.com with SMTP id 586e51a60fabf-1a28de15c8aso5465394fac.2 for ; Wed, 14 Jun 2023 09:34:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1686760495; x=1689352495; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=P02UcLI2//J8LvUgRFLkUqu+ureKnlEB4HrY9Uc3j4k=; b=J0jSJqDukYcfhA7sISg8YT5j2AJRPy7WWscY0Pmtmu1xD+4jgXykkAo2CVR7ZJbtH2 LxJMgSOX9Tg84S4auSG+Dq4bdv6+pfcoAoGw0s+Kk3HbW7J93Rt+B3bMKIPPwBykdcai dUor7roPb9xBLCf2UMlIcU4vkKdW4qmSSnleDsM6wQxxBd/MhNTCJSUlnsOHyI73W7sb QR3xW8HF6/YWt7RuA0xR79c2aH0UnKegkHc+zZyDEGgOgp02w6poDo5FYWyG0LTlDF3n juTk/s3ZSRipEKSmANiG9qYT4AmNRq8DglCgqd8Imj5iR7qnG2im3Oa8eFSh/8ZmjGCl ZNiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686760495; x=1689352495; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=P02UcLI2//J8LvUgRFLkUqu+ureKnlEB4HrY9Uc3j4k=; b=a+QLmNzVXuRXGf9lI6bDkYQUY2NbITQPjatU0k2X7POFh9ydwLczifL/Ptq3PooIVK CRZtmEnKK5dIGB2RDYI5LzNqXZ3tK0TVRvur5PVdfw+9b5c3t5S/+9+orElgd5QGRkWT U4ix09MTmcVLj+AfZs6QGNAVKXVLAanw4+1Itwjlr/LnFmIiJTcqCcs0vVmMqEPXgRV/ s5dskYKuU1whmfzCKUFlRCpmk98LzQP8r7XmbZa9xkXwM4qp17h57JUCFkJuQW8yGdGS UodtHSHHM6OCXphyigo7454B6QmJXpZQ7bUjfKNC/YlcdZWwLbOu7JKJuPzLQQE6A5Sn Vmrg== X-Gm-Message-State: AC+VfDyTpGs6fD7PKEnOSdNV0NSHiHvkgGTLZwTEtdhTEyDKExRzeyTa IUgJzNrPIBgvSjyo8prpf98= X-Google-Smtp-Source: ACHHUZ6LPh/lBfJJZiZ/JXibWTrWDOw5+WfS7pNTIAJ13gUHKTNkU1bHLYeyD6Kf/khV7txSsY69SA== X-Received: by 2002:a05:6870:a695:b0:19e:475:9df1 with SMTP id i21-20020a056870a69500b0019e04759df1mr13490656oam.27.1686760494607; Wed, 14 Jun 2023 09:34:54 -0700 (PDT) Received: from [192.168.54.90] (static.220.238.itcsa.net. [190.15.220.238]) by smtp.gmail.com with ESMTPSA id ld10-20020a0568702b0a00b001762ce27f9asm8848922oab.23.2023.06.14.09.34.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 14 Jun 2023 09:34:54 -0700 (PDT) Message-ID: <6e61f06f-2411-0bcb-926b-0a6927096f20@gmail.com> Date: Wed, 14 Jun 2023 13:30:54 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Subject: Re: [PATCH] rust: allocator: Prevents mis-aligned allocation Content-Language: en-US To: Boqun Feng , rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Gary Guo , =?UTF-8?Q?Bj=c3=b6rn_Roy_Baron?= , Benno Lossin , Alice Ryhl , Dariusz Sosnowski , Geoffrey Thomas , Fox Chen , John Baublitz , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Kees Cook , Andreas Hindborg , stable@vger.kernel.org References: <20230613164258.3831917-1-boqun.feng@gmail.com> From: Martin Rodriguez Reboredo In-Reply-To: <20230613164258.3831917-1-boqun.feng@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: BF32080017 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 5nwd6ogciumtnxgcmw8zmn5mgnosr4so X-HE-Tag: 1686760495-450763 X-HE-Meta: U2FsdGVkX18fuEEKrHgQRVetxmTxHU2CSshFxcV0jdTvKFtWQTTDToaQT5o5d3heCqEUM44alnMA84u/cXA2UxHkMdsG6sWYhWNyv0vFNlyVyU04VHjZxAngDNnYKjY/RZY8cw7Cvork0y2Frg3d9jAVBjZ+cQ6UdWdbGMn4jyAg/7GZhxt7lbi7qgFpin5f4MaSgRMC6kWcfzKGjYGv5DcQd9eQFxuBOSPBJgf6Ka8lMmNSlBHAfYVNB0hN3tNlTumst46GH2bD4EF2T/dmxjeJL2iO1SZYz5PMfML09WI2iX2G5G2EPbSHsUEjwmaPueUFdWgNJzzSkYPfZ4i/937buZ171Ss0uaVkG5hNQeUPg/uk7qvX8UMetp8qL6Qe85Q1gQXh/DvLkfSKT9eygEBxIYgMirmYei9zpsxgskdNLZTzQ9ODvSkhoOkQqMjg734ZrcF1Co84V+GUqtF26InTZQBgwhHSRRCCvKDykDdOa3Eq8jldfvxg8uskEHcjOiNWM7IxDyu4Q/URFDRqsxlaG/8hscuMav77eZ8cSsvmKri69NAri8MCzqSsBJbplALQXGCdHFAGmMFmCrqfBOPDGjt/fxt6CyV3eUwiURHkAD8T+/JKIhtZeYQj+3xYqGYoHyhbGW/tWRhJL5jwFIpskRZpTO86wUmO8kXxmFlnQpNjtJE2MBzvB7mDmrpWaJJ4fAssH/OF7AsmQJj5elLXojIAh9N7BSSz+Y38VZ1KubsXXYFD3LkL7nEt96Fja2Zh0L4ZZr4OmN9oNOTZbxIFADkBMs2kuE6YqVN+5I1k4KxIXXNDdXY7QHLTSnwAhldHXcdgfpAPkNIORohu8QvGOZ/LMLY0Fzz9dZsl+QXQXAdrFD8AZ5rtSgt8srX+BXAhGydJT4Wcdjjma341/W89yGfPt85oAJKfUMTDE0C/jaiB+I7IK28qAENK5lFjoxUsfM4SWrlisMuuKWN kidDowPn 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 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: On 6/13/23 13:42, Boqun Feng wrote: > Currently the KernelAllocator simply passes the size of the type Layout > to krealloc(), and in theory the alignment requirement from the type > Layout may be larger than the guarantee provided by SLAB, which means > the allocated object is mis-aligned. > > Fixes this by adjusting the allocation size to the nearest power of two, > which SLAB always guarantees a size-aligned allocation. And because Rust > guarantees that original size must be a multiple of alignment and the > alignment must be a power of two, then the alignment requirement is > satisfied. > > Suggested-by: Vlastimil Babka > Co-developed-by: Andreas Hindborg (Samsung) > Signed-off-by: Andreas Hindborg (Samsung) > Signed-off-by: Boqun Feng > Cc: stable@vger.kernel.org # v6.1+ > --- > [...] Reviewed-by: Martin Rodriguez Reboredo