From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1323FC433EF for ; Thu, 14 Oct 2021 07:57:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E7930610F9 for ; Thu, 14 Oct 2021 07:57:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230123AbhJNH7s (ORCPT ); Thu, 14 Oct 2021 03:59:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229967AbhJNH7r (ORCPT ); Thu, 14 Oct 2021 03:59:47 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E02ACC061570 for ; Thu, 14 Oct 2021 00:57:42 -0700 (PDT) Received: from zn.tnic (p200300ec2f0c72004cd8e1678c0b16c3.dip0.t-ipconnect.de [IPv6:2003:ec:2f0c:7200:4cd8:e167:8c0b:16c3]) (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 3ECF21EC03EA; Thu, 14 Oct 2021 09:57:41 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1634198261; 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=RLbTK0HRgG5pyCuStO02HK9+Id9iOaym4Axzlf6nny0=; b=ScMbOH7AXJPOCt+bcyatjILnCcnqdxt6B1ahhtXBPsjXlSgSS36bm7Z9dGG7TboUz9IEDO MQIYFSvvmO3fgSYwB2ou74z8ucYqRTKtQLq7+jC9X0pETjkmw8ulWLl/8pHr4bpnZ5lWoz hKUF9Vz/zluqFpiLc3jpkJNzGdlsu7M= Date: Thu, 14 Oct 2021 09:57:40 +0200 From: Borislav Petkov To: Josh Poimboeuf Cc: Thomas Gleixner , Kuppuswamy Sathyanarayanan , Ingo Molnar , x86@kernel.org, Paolo Bonzini , David Hildenbrand , Andrea Arcangeli , Juergen Gross , Deep Shah , VMware Inc , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Peter H Anvin , Dave Hansen , Tony Luck , Dan Williams , Andi Kleen , Kirill Shutemov , Sean Christopherson , Kuppuswamy Sathyanarayanan , linux-kernel@vger.kernel.org Subject: Re: [PATCH v10 03/11] x86/cpufeatures: Add TDX Guest CPU feature Message-ID: References: <20211009053747.1694419-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20211009053747.1694419-4-sathyanarayanan.kuppuswamy@linux.intel.com> <20211013194251.ndbyj45egz6msl63@treble> <87wnmg7bt0.ffs@tglx> <20211014002506.2rqkgzrvy5ki2rcw@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20211014002506.2rqkgzrvy5ki2rcw@treble> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 13, 2021 at 05:25:06PM -0700, Josh Poimboeuf wrote: > I think Boris said that's not possible because of some ordering > reasons which are eluding me (and I didn't have time to investigate). The obvious one being that CPU caps aren't set yet. And then there was this wild goose chase about fixup_pointer() and whether the compiler generates rip-relative addressing to global vars in early boot code which runs out of 1:1 mapping and could be loaded somewhere else... So I'm not opposed to doing cap flags - that would get rid of the new flags but it needs to be done carefully because with early boot, the devil's in the detail. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette