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X-CSE-ConnectionGUID: ZM5CIsIWRVi8P5+WNyhVkQ== X-CSE-MsgGUID: WGQdFigtRyC0Sp8NlSa1Ig== X-IronPort-AV: E=McAfee;i="6800,10657,11880"; a="90191650" X-IronPort-AV: E=Sophos;i="6.25,231,1779174000"; d="scan'208";a="90191650" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2026 08:26:54 -0700 X-CSE-ConnectionGUID: yYD3B8nlQSOelBEaJXlbbw== X-CSE-MsgGUID: VsFntrBzRlKh9umXn3/iAg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,231,1779174000"; d="scan'208";a="303798623" Received: from sghuge-mobl2.amr.corp.intel.com (HELO [10.125.108.15]) ([10.125.108.15]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2026 08:26:54 -0700 Message-ID: Date: Wed, 19 Aug 2026 08:26:53 -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: [linus:master] [x86/bugs] a3af84b0fa: stress-ng.seccomp.ops_per_sec 95.7% regression To: kernel test robot , Pawan Gupta Cc: oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, Daniel Borkmann , Dave Hansen References: <202608191340.98574fe2-lkp@intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/18/26 23:20, kernel test robot wrote: > kernel test robot noticed a 95.7% regression of stress-ng.seccomp.ops_per_sec on: One one level this is a "vulnerability mitigations cause performance loss, news at 11" kind of thing. Like, Duh! The microbenchmark here does seem to be a pretty worse-case scenario where it sits in a loop loading and running a seccomp filter program. In other words, it's just about as pathological of a test as you can have. I think Pawan had some more ideas about ways to optimize this. Is there any appetite for that? Or is the test just too synthetic to worry about?