From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: X-Spam-Status: No, score=0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_SOFTFAIL,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.6 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7CD2C433EF for ; Wed, 9 Mar 2022 15:48:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233976AbiCIPty (ORCPT ); Wed, 9 Mar 2022 10:49:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232908AbiCIPty (ORCPT ); Wed, 9 Mar 2022 10:49:54 -0500 X-Greylist: delayed 16117 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 09 Mar 2022 07:48:54 PST Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C77AB123428; Wed, 9 Mar 2022 07:48:53 -0800 (PST) Received: from zn.tnic (p200300ea97193859703755baa7c6e9ad.dip0.t-ipconnect.de [IPv6:2003:ea:9719:3859:7037:55ba:a7c6:e9ad]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id B23A51EC04A6; Wed, 9 Mar 2022 16:48:47 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1646840927; h=from:from: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:in-reply-to:in-reply-to: references:references; bh=La1XrlyNpE+yY/g5MBtL2GPKP7BcdtWqaFLgaoB6dTM=; b=GxaD8VCMNowjJlO+ctS/0njsHg/FhTIspM8DkSkoSe0F6jy2R2HWvtUiUxcnPNwmbP2v1r 3BReKBmGh7ZqqxOZzdqEVcXuICENQR2lgHppr+LZRlCFXrafDq8Vakt2a8fbGffSZ/V9Z/ FNwKr68Jj0P/ALopSenTalhZqs7qwac= Date: Wed, 9 Mar 2022 16:48:53 +0100 From: Borislav Petkov To: Dave Hansen Cc: Cathy Zhang , linux-sgx@vger.kernel.org, x86@kernel.org, lkml Subject: Re: [RFC PATCH 09/11] x86/microcode: Expose EUPDATESVN procedure via sysfs Message-ID: References: <20220309104050.18207-1-cathy.zhang@intel.com> <20220309104050.18207-10-cathy.zhang@intel.com> <35449b18-d77e-387b-f802-48f8013dfdf9@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <35449b18-d77e-387b-f802-48f8013dfdf9@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Wed, Mar 09, 2022 at 07:42:21AM -0800, Dave Hansen wrote: > There's a little bit in the cover letter that _implies_ why EUPDATESVN > isn't called during the actual microcode update: > > > This series implements the infrastructure needed to track and tear > > down bare-metal enclaves and then run EUPDATESVN. This is expected > > to be triggered by administrators via sysfs at some convenient time > > after a microcode update, probably by the microcode update tooling > > itself. > > This allows the (non-destructive) ucode update and the destructive > EUPDATESVN procedure to happen at different times. Which means, that this has even less to do with the microcode loader. That whole glue can be somewhere in arch/x86/...sgx/ land and be completely independent. > If we just want to make the ucode update itself call EUPDATESVN via > microcode_check(), that makes the ucode update itself destructive to SGX > enclaves. That's not the end of the world, but this series is going to > some amount of trouble (including new ABI) to avoid it. > > Perhaps we need to hear more about why this is so much of an issue. Yah, it all sounds weird. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette