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X-CSE-ConnectionGUID: hqKqNdtGS8WVZt9HXjCdvw== X-CSE-MsgGUID: DYz9T3lhRnCPWj+k7+SFAg== X-IronPort-AV: E=McAfee;i="6700,10204,11414"; a="47363969" X-IronPort-AV: E=Sophos;i="6.15,238,1739865600"; d="scan'208";a="47363969" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Apr 2025 11:04:59 -0700 X-CSE-ConnectionGUID: pHmo2QjvRJu4Mo68JdEEIQ== X-CSE-MsgGUID: SULpJ2zHScmrAwn52PZxdQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.15,238,1739865600"; d="scan'208";a="138063280" Received: from uaeoff-desk2.amr.corp.intel.com (HELO [10.124.222.49]) ([10.124.222.49]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Apr 2025 11:04:58 -0700 Message-ID: <0d7d6b9a-e7bd-4225-8f08-05bd9473a894@intel.com> Date: Fri, 25 Apr 2025 11:04:56 -0700 Precedence: bulk X-Mailing-List: linux-sgx@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 2/2] x86/sgx: Implement EUPDATESVN and opportunistically call it during first EPC page alloc To: Sean Christopherson , Elena Reshetova Cc: "jarkko@kernel.org" , Kai Huang , "linux-sgx@vger.kernel.org" , Vincent Scarlata , "x86@kernel.org" , Vishal Annapurve , Chong Cai , Asit K Mallick , Erdem Aktas , "linux-kernel@vger.kernel.org" , "bondarn@google.com" , "dionnaglaze@google.com" , Scott Raynor References: <20250415115213.291449-1-elena.reshetova@intel.com> <20250415115213.291449-3-elena.reshetova@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 4/25/25 10:40, Sean Christopherson wrote: > So then why on earth is the kernel implementing automatic updates? Because it's literally the least amount of code and doesn't create any new ABI. > I read back through most of the cover letters, and IIUC, we went > straight from "destroy all enclaves and force an update" to "blindly > try to do EUPDATESVN every time the number of enclaves goes from > 0=>1". Those are essentially the two most extreme options. I'm sure we can think of a bunch more extreme things. How about after every ENCLS? ;)