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 35731C25B74 for ; Fri, 24 May 2024 03:30:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B74196B0093; Thu, 23 May 2024 23:30:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B24396B0095; Thu, 23 May 2024 23:30:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9C4266B0096; Thu, 23 May 2024 23:30:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 7A7036B0093 for ; Thu, 23 May 2024 23:30:26 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 30BDB1C08F8 for ; Fri, 24 May 2024 03:30:26 +0000 (UTC) X-FDA: 82151861652.02.BF11421 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) by imf03.hostedemail.com (Postfix) with ESMTP id DB97520010 for ; Fri, 24 May 2024 03:30:23 +0000 (UTC) Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=RmVazsIa; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf03.hostedemail.com: domain of dave.hansen@intel.com designates 198.175.65.11 as permitted sender) smtp.mailfrom=dave.hansen@intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1716521424; 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=JHKMfm1mYmtXWBvQ7k66+MqPWlnoYo7Iqfi7HLGaxm0=; b=rF4yMX78cwOSAKyqUfzL5R+WlsF3DLf1VC5hrUavw4Tl+bUF3vgGcAbR7L7FzHggquZzn/ ll7dS3OizUbNuGjh9X3dcdIAXautUUBXVOcs2gIbfT5jpsy+WNVP1WBcLF13DIuQjus9nV EHtjYejOcG5heOZzV6nskVJqWZ1Vy4E= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=RmVazsIa; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf03.hostedemail.com: domain of dave.hansen@intel.com designates 198.175.65.11 as permitted sender) smtp.mailfrom=dave.hansen@intel.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1716521424; a=rsa-sha256; cv=none; b=3nzHKBTGE1JO9uT/jGvWmyHXPN4JKi6K9KQqKgnI+cSq1lsH5B2Fo3s2wvyU9PTvJ2oiZm /hnsQujfXMYm/KUxZV9sCZnZX0Ix48e975U8wQ7pkfx+9Jl1U/DbdNuqhT35cxN60qoZ8L Bxi8AvJRBzbTABEQkpSXCcBw7WdNUEA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1716521425; x=1748057425; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=xkaLxk4meNwxWBCKUk3E7glOS8Ot23OguWIkyNFPEUM=; b=RmVazsIaf8/lHINdf9VKnlkH5bd8A3iLLfzUn2w4UMmeuGhcstN+pFww aktrkji/CN7DRUx/+WXkasj4pDlQ/1RUHqW7ITKBlaZspsOEVnMb7HE8q ADSMMKqxc3bFWMG2csJ7l0kps+0FvBSOkPx+YkOdVj8GnpOX0RnBNhtGO +5CpDlTyoKxpBwCqQYCUlAGsH6RdKSMhfJVDeDHamkAO5Z9qWuVuNp87w p52yzdHXwGb24eNVyVEpo0GllQpVvwmX/OKOuigbrbp8wyZu/gqVA10zv u22uYvb7KqJuM3e88esrL6b44MNZ9FDRb60FCNWkfNEpo2W74+OBsFhU8 g==; X-CSE-ConnectionGUID: cvhsmRWQSTq8pLNbUzdB4g== X-CSE-MsgGUID: XF5lGOOCRNqsNdiAdVequw== X-IronPort-AV: E=McAfee;i="6600,9927,11081"; a="23452524" X-IronPort-AV: E=Sophos;i="6.08,184,1712646000"; d="scan'208";a="23452524" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2024 20:30:23 -0700 X-CSE-ConnectionGUID: g06c64MBQqKNBaY6L2tqyQ== X-CSE-MsgGUID: jv2LXXkZQfikazMCp6mktA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,184,1712646000"; d="scan'208";a="33802324" Received: from unknown (HELO [10.125.110.91]) ([10.125.110.91]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2024 20:30:21 -0700 Message-ID: <7b6b6430-0237-4512-b99b-9eb815b3dc68@intel.com> Date: Thu, 23 May 2024 20:30:19 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC 2/2] mm/x86/pat: Do proper PAT bit shift for large mappings To: Peter Xu Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Thomas Gleixner , Jason Gunthorpe , Andrew Morton , Al Viro , Dave Hansen , Andy Lutomirski , Matthew Wilcox , Dan Williams , "Kirill A . Shutemov" , Mike Rapoport , Ingo Molnar , Michal Hocko , Alex Williamson , Peter Zijlstra , Suren Baghdasaryan , Borislav Petkov , x86@kernel.org References: <20240523223745.395337-1-peterx@redhat.com> <20240523223745.395337-3-peterx@redhat.com> From: Dave Hansen Content-Language: en-US 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: DB97520010 X-Stat-Signature: o19ay65issehhf8tpmdgc86sgr77mt36 X-HE-Tag: 1716521423-543265 X-HE-Meta: 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 Qo7Y8QiM ho/ioPdXv4nfzWbkmebytlpyDASGxcZqqLjZktrEau0hsSH0fh0F2Abfwfjy92iPDuqQooN9Br13a1MGFSgLUW6FwZhFi3h2GSZtzr3wQrZUeqiYhiAtab1bi8Mu8KxXemenYjo+dN2iGbDch8tIIp2zKXkBMjPuB2xOOqqWmNq5zWY7iOetUyFepBA== 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 5/23/24 16:07, Peter Xu wrote: > Probably not.. I think I can define a pgprot_to_large() globally, pointing > that to pgprot_4k_2_large() on x86 and make the fallback to be noop. And > if there's a new version I'll guarantee to run over my cross compilers. I guess that would be functional, but it would be a bit mean to everybody else. > Any comments on the idea itself? Do we have a problem, or maybe I > overlooked something? I think it's probably unnecessary to inflict this particular x86-ism on generic code. The arch-generic 'prot' should have PAT at its 4k (_PAGE_BIT_PAT) position and then p*d_mkhuge() can shift it into the _PAGE_BIT_PAT_LARGE spot.