Received: by 2002:a05:7412:d1aa:b0:fc:a2b0:25d7 with SMTP id ba42csp1761723rdb; Wed, 31 Jan 2024 08:18:18 -0800 (PST) X-Google-Smtp-Source: AGHT+IGK7tChPcbvlnIk1Zn2mrv/Vic139lHYEebNOMo+qVhtQBuOnMtfr8CYZeRtHB5vhqriDFn X-Received: by 2002:a17:906:89b:b0:a36:a153:1828 with SMTP id n27-20020a170906089b00b00a36a1531828mr240849eje.75.1706717898477; Wed, 31 Jan 2024 08:18:18 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706717898; cv=pass; d=google.com; s=arc-20160816; b=gQToOdWYL8gJimklxy7RIogSOul6C4xwN0FHZ9odMW1lgZ4oKPuxQKF8r2DMlfVW7m 8tsq2UUE1QKFVmPk7/zjrD97lN5hbTdwgWMWWihcqDKuKG3pwaOTgY+ToYducNCBGNc/ sp/dyvH+dZc5le6TZelxh34prlV60JKzop/wsuZy9aD/Y9MysnoiydSnlfLwaFyYbhdJ +KLNRr8Yt+5Kr86l3mYCmOjc6jghepHyx9gTbsM9j7W4JOsPaCuiarUegNvdc31TWJMB Cb7eAb+vpeHkMBg/eRTGu97XWEsnk5Sqt75HYUrJnRT24/xuW9sCcK5oKMGQY7Xtu7KX l2/g== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version :list-unsubscribe:list-subscribe:list-id:precedence:date:message-id :dkim-signature; bh=hGmya1IUnelaIjMynIgu31ik+NviP+kMumKNYz5T/Xk=; fh=kK8pyvPXIz3pNRzXJcMo+BvDda+ZignmJ75Q26EQg2M=; b=CL4rumDfGocVHEjyFvrI27wS8xPjxj4TQKwAK5WjYaGa1qwaEM4N6VGAuszrZO71rB +GXeYtmLr8kmW2OPKy368VWNITs/v9icBzWlmMPcstzaFlomKL9tg+QyBHLrOCj18wSG 9dGCwMzxEJCKzDmdTvfx1JV4IlIPc/6lt/b5o0S//e2CEZyj990a77DrUQdWyPgmlHKB ym4k9FVmpymH8mJT5kGKU7W0TuGPXCEhXtQeaX6DP6dA0E0Ic1VDHkv6FPHPTYN7mTMS SYMRS0dcdnHoUmxpSmgRg5HTDW0PWjGCPtIUTSdwLykzqMl4VcsiDlUcmpSIn0vmzYoE A0hA==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=DA9zV1fd; arc=pass (i=1 spf=pass spfdomain=intel.com dkim=pass dkdomain=intel.com dmarc=pass fromdomain=intel.com); spf=pass (google.com: domain of linux-kernel+bounces-46775-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) smtp.mailfrom="linux-kernel+bounces-46775-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com X-Forwarded-Encrypted: i=1; AJvYcCWGWFY8aYZuYYxOBS5hQBdx+bTHc4R9jwxHLb1QCntWPDGFjxlHOVPvVPVUIFhRFlbGLYxrGJKfOcbkcb0SWFWsz7A0efrhtRwsIpNWrQ== Return-Path: Received: from am.mirrors.kernel.org (am.mirrors.kernel.org. [2604:1380:4601:e00::3]) by mx.google.com with ESMTPS id o1-20020a17090608c100b00a355900f685si4116644eje.582.2024.01.31.08.18.18 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Jan 2024 08:18:18 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-46775-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3; Authentication-Results: mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=DA9zV1fd; arc=pass (i=1 spf=pass spfdomain=intel.com dkim=pass dkdomain=intel.com dmarc=pass fromdomain=intel.com); spf=pass (google.com: domain of linux-kernel+bounces-46775-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) smtp.mailfrom="linux-kernel+bounces-46775-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id 134B11F2BEB0 for ; Wed, 31 Jan 2024 16:18:18 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4600412AAF4; Wed, 31 Jan 2024 16:17:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="DA9zV1fd" Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8995312A146 for ; Wed, 31 Jan 2024 16:17:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706717840; cv=none; b=okfK757/urOMeCElkyYrQS00TP9c8FHoXz1UkimNdWdK6ui0NpFX7BF869cKPwBWakBgUJDJH8/iJJBgpN2P4NXp65x0DbFWLj0oYIovAVEXINB5E5FaLSLFV22k9fzlHpD1ympEU3wsV8e30dzJDafhzB7+62CFqMG+p7sXjuk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706717840; c=relaxed/simple; bh=ZBvftZEA8h+jPKNWGdCM8l+DDEkktcde2JqVYxQKRIU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=quJ8aJamyPn/xQOr9+2VSTnVSpT7802MFRpRpp+dkgR3h/UWAccQ1Iq+7esvqLIzy2w3OkTWzWhoPj1jSJf679QP/MrQ0jtyh2lu0K51oAvvfu9jKOEY6vVvd2GiQzv5c1koxmKu30ijutuKPKU7pZ8Y4i35fyQfWZrDbHkVr4g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=DA9zV1fd; arc=none smtp.client-ip=192.198.163.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1706717838; x=1738253838; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=ZBvftZEA8h+jPKNWGdCM8l+DDEkktcde2JqVYxQKRIU=; b=DA9zV1fdsGd1ty+1wGc4B6ac1Kpd1V03m0ZfTxgIUbeYSGoJe2vcL7d+ Vwv+dS3OEvkDRLmAVHSfP9GRy43C/nrozgUARAp5Ry8PANPlqFR0Kd4qT gvgc+oSQkxmdzpOH2XT4VIMQVNT0N5VFAF0CfqQdkXmTDw/0j/TxtsQ9L 7qinvr7m66kPNYEMdyFQVRJkvPD4SURPZ4bohfEJSNLLqPlXWrMJpShHu annkB+g1KOQej7EPgf9XgeXMLiE/0IZ8KtKeGEpR7cRcJNLofk6v5s8Tf 27yWx2LxMPKoXa3HpugHGbjQJ2F3EzC58qR/uE6YF3W0doA6smPZQCfHW g==; X-IronPort-AV: E=McAfee;i="6600,9927,10969"; a="2583358" X-IronPort-AV: E=Sophos;i="6.05,231,1701158400"; d="scan'208";a="2583358" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jan 2024 08:17:17 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10969"; a="822613711" X-IronPort-AV: E=Sophos;i="6.05,231,1701158400"; d="scan'208";a="822613711" Received: from dspeerx-mobl.amr.corp.intel.com (HELO [10.212.131.185]) ([10.212.131.185]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jan 2024 08:17:16 -0800 Message-ID: Date: Wed, 31 Jan 2024 08:17:15 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC V1 4/5] x86: CVMs: Allow allocating all DMA memory from SWIOTLB Content-Language: en-US To: Vishal Annapurve , x86@kernel.org, linux-kernel@vger.kernel.org Cc: pbonzini@redhat.com, rientjes@google.com, bgardon@google.com, seanjc@google.com, erdemaktas@google.com, ackerleytng@google.com, jxgao@google.com, sagis@google.com, oupton@google.com, peterx@redhat.com, vkuznets@redhat.com, dmatlack@google.com, pgonda@google.com, michael.roth@amd.com, kirill@shutemov.name, thomas.lendacky@amd.com, dave.hansen@linux.intel.com, linux-coco@lists.linux.dev, chao.p.peng@linux.intel.com, isaku.yamahata@gmail.com, andrew.jones@linux.dev, corbet@lwn.net, hch@lst.de, m.szyprowski@samsung.com, bp@suse.de, rostedt@goodmis.org, iommu@lists.linux.dev References: <20240112055251.36101-1-vannapurve@google.com> <20240112055251.36101-5-vannapurve@google.com> From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: <20240112055251.36101-5-vannapurve@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 1/11/24 21:52, Vishal Annapurve wrote: > --- a/arch/x86/mm/mem_encrypt.c > +++ b/arch/x86/mm/mem_encrypt.c > @@ -112,10 +112,14 @@ void __init mem_encrypt_setup_arch(void) > * The percentage of guest memory used here for SWIOTLB buffers > * is more of an approximation of the static adjustment which > * 64MB for <1G, and ~128M to 256M for 1G-to-4G, i.e., the 6% > + * > + * Extra 2% is added to accommodate the requirement of DMA allocations > + * done using dma_alloc_* APIs. > */ > - size = total_mem * 6 / 100; > - size = clamp_val(size, IO_TLB_DEFAULT_SIZE, SZ_1G); > + size = total_mem * 8 / 100; > + size = clamp_val(size, IO_TLB_DEFAULT_SIZE, (SZ_1G + SZ_256M)); > swiotlb_adjust_size(size); > + swiotlb_adjust_alignment(SZ_2M); FWIW, this appears superficially to just be fiddling with random numbers. The changelog basically says: "did stuff". What *are* "the requirement of DMA allocations done using dma_alloc_* APIs"?