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 3E45739B976 for ; Mon, 30 Mar 2026 19:46:58 +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=1774900020; cv=none; b=pz04NTYQz9ihbGXkqg3ARMiYDfkREBfFK4Fies9MQYT3oEKGjid4N8yUtf953RpqSCQ1JikY4oUUay67hR2UnnzDl3x57J2yBtPghq1I3icyrFI0MVcA0ho3xZgbNjDbLz1l3JRI6IYOgLu7v23g161jStc/pI6O1+CXtGVhuMI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774900020; c=relaxed/simple; bh=RM5ZF3TluCRGAx3kxtvQuJ8mxf50SSNTAl7vJVvV4Iw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=SN5FNF46DH/dEoX83oYrp4EUS+Chhof5yhZ6HUdbqwydrpI0K0AMpedogKNzCv8dk7Gg8r+P7rnIpzya3cWNfvZOVCZN1WD4BtiZUN1Q3uZH93fnBxG/v4niE0f23yPOqGfqwBpWJ0JaQ/pr9iBjLgQdqHWK6IZ66gNrWKWqzhI= 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=VNUyyUqJ; 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="VNUyyUqJ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1774900018; x=1806436018; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=RM5ZF3TluCRGAx3kxtvQuJ8mxf50SSNTAl7vJVvV4Iw=; b=VNUyyUqJ45GJVuVAn/v63PLYkzMaAyYnVTxGXZ7xEaV4u9oiQbobRER6 x+wlG+rs4sG9Yp6B7pV9lvvjoiHdkG3nYvDoQMjbShC8nTrWd4gKg3wG8 SjGCmR0E2Ce+0ASjsJoQZqwy0k1LWWsLk5Hb+1Jt8Nbzsk2ES7PBHRIh/ rTdVy6Ys08ZXVEA1WbFrnmjLzu8q+5g7OUU0SKAPRWy0VLq2NDi0EaERs FitT8C2ipo2s4gxaRjgAussLHd0bsCJqQJbTvnlMBzn3lFLOUptr59fjl 833dlv+9QbW7T8lfeu6I6DPDhMQ5+P2DnlIXcqPQQoV6kQ+YzFJs1PXZa A==; X-CSE-ConnectionGUID: nQS51xyrRSyu50MFhfQRXQ== X-CSE-MsgGUID: tCwZiCGQS5Cmz/liK2O9Xg== X-IronPort-AV: E=McAfee;i="6800,10657,11744"; a="87372772" X-IronPort-AV: E=Sophos;i="6.23,150,1770624000"; d="scan'208";a="87372772" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2026 12:46:57 -0700 X-CSE-ConnectionGUID: ci+HMGZ3TEuYDE+fJg5ryw== X-CSE-MsgGUID: oF2kvZ6LT9yURYONSru8aA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,150,1770624000"; d="scan'208";a="222836688" Received: from sghuge-mobl2.amr.corp.intel.com (HELO [10.125.110.248]) ([10.125.110.248]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2026 12:46:56 -0700 Message-ID: <55d3ba47-e609-4b22-911f-047d08dc3864@intel.com> Date: Mon, 30 Mar 2026 12:47:02 -0700 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: [PATCH next] i386: Remove string functions that use 'rep scasb' To: David Laight , Andy Shevchenko Cc: Andrew Morton , Andy Shevchenko , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Uros Bizjak , linux-kernel@vger.kernel.org, Kees Cook , Linus Torvalds References: <20260327195747.89556-1-david.laight.linux@gmail.com> <2f763ca6-794e-4b5a-9b92-9a9cc8858cd2@intel.com> <20260330202014.1eb6fc76@pumpkin> 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: <20260330202014.1eb6fc76@pumpkin> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/30/26 12:20, David Laight wrote: > I have Intel Quark at hand to test. But I need to know the > step-by-step instructions on what to do. I'll take it if it's all that we have, but Quark is really weird. It's probably Intel's last sold 32-bit-only CPU, but it wasn't used for anything remotely performance sensitive, it's more like a 1995 CPU than a 2010 CPU, and Intel probably sold like twenty of them. ;) But, seriously, we don't need to go digging in the junk heap for performance numbers. If nobody has one handy, it's just extra justification for "we don't care". But let's just say *THAT* instead of doing some kind of performance theater where we pretend that like every cycle on CPUs from 2003 matters on a 2026 kernel, and that we even cared enough to measure it.