From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (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 68E671C84A6; Mon, 13 Oct 2025 14:06:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760364418; cv=none; b=SfjuymocayDfogZX0lcDM+sLKTNwA8pE1H8/BVrhDAQCG/F1z5F8HbytU9ULvoQjBaij9/5ClEWOK4RUgDkElxAFIj7m90bj9hNCu4ztOwj2uBKh+cidfzuNs/H7oLioVP+okwkFCp+D0HfNEHsYcSNMC4LdTPHEk+IbI0UmAn4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760364418; c=relaxed/simple; bh=L5mJoBb6ix5GBpByToQiDe5tqBFj7Zbr19ly3L1L3KI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=cMIwTdumXXebpCUDzIXCtMYnRKEzuvCH1qZwcdKWxwkBC5rWuzqDbz17uCOnNR2puuWQvfFnUkNXkUiiXaooP4HXkKWAp5vWQvylhHP0n/A+/Hq4xffL2+S04uFIYrpwv2RtKezaGm1X9i8MG+46GEbSbyEPxSVz1/Gul6aY5TM= 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=YaL1Lc2O; arc=none smtp.client-ip=198.175.65.12 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="YaL1Lc2O" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760364418; x=1791900418; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=L5mJoBb6ix5GBpByToQiDe5tqBFj7Zbr19ly3L1L3KI=; b=YaL1Lc2Omy7qI9scQjYqvVrPDt3IBuYgas97ODu3NZgxuPXDbBA/vBHI yjtewhM4xrSAaTlTwetf6Kg5VjKyxdtIGyIxfqG4TSREnr2umxtr5WwD0 4gERmaDzqqtue/XyWPCdEWcx1Nzp6qCCciFH/NqzRBNVs4Eb+vDBrRatr mvz/gq70YCjuyfbgTKiBVp2XqxqO90W0dw5WvGE+Fo054fdtFNBXRtj7Z dmTw4dzxCxDS7nBd2TYj9bJ8SNpZXwJF6dd6FsQ8aaDyLjWaAaT6T/NVL /cj1UbVeEHHA4UBZ4uX6JQTwBTUGwAo0CK6hRD5YQcLaNbJkmCbUBoVeH g==; X-CSE-ConnectionGUID: 4dC+1mT+RsyRHFucUrQ2vg== X-CSE-MsgGUID: wcOO+dXLQluY58daM+MB+A== X-IronPort-AV: E=McAfee;i="6800,10657,11581"; a="73946677" X-IronPort-AV: E=Sophos;i="6.19,225,1754982000"; d="scan'208";a="73946677" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2025 07:06:57 -0700 X-CSE-ConnectionGUID: uNRTtnxdRKStoMWW6widHg== X-CSE-MsgGUID: WCIV4fbYShWKbukyiTN2yA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,225,1754982000"; d="scan'208";a="186691282" Received: from aschofie-mobl2.amr.corp.intel.com (HELO [10.125.111.123]) ([10.125.111.123]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2025 07:06:57 -0700 Message-ID: Date: Mon, 13 Oct 2025 07:06:55 -0700 Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] vdso: Remove struct getcpu_cache To: =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= , Huacai Chen , WANG Xuerui , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Richard Weinberger , Anton Ivanov , Johannes Berg , Vincenzo Frascino , Shuah Khan Cc: loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20251013-getcpu_cache-v2-1-880fbfa3b7cc@linutronix.de> 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: <20251013-getcpu_cache-v2-1-880fbfa3b7cc@linutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 10/13/25 02:20, Thomas Weißschuh wrote: > -int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused); > -int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused) > +int __vdso_getcpu(unsigned int *cpu, unsigned int *node, void *unused); > +int __vdso_getcpu(unsigned int *cpu, unsigned int *node, void *unused) > { > int cpu_id; It would ideally be nice to have a _bit_ more history on this about how it became unused any why there is such high confidence that userspace never tries to use it. Let's say someone comes along in a few years and wants to use this 'unused' parameter. Could they?