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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57661C48BCD for ; Wed, 9 Jun 2021 14:33:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 377026139A for ; Wed, 9 Jun 2021 14:33:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237146AbhFIOex (ORCPT ); Wed, 9 Jun 2021 10:34:53 -0400 Received: from mail.skyhub.de ([5.9.137.197]:41828 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234734AbhFIOes (ORCPT ); Wed, 9 Jun 2021 10:34:48 -0400 Received: from zn.tnic (p200300ec2f0cf6002c8ea3a9506b9c3f.dip0.t-ipconnect.de [IPv6:2003:ec:2f0c:f600:2c8e:a3a9:506b:9c3f]) (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 8EC981EC0516; Wed, 9 Jun 2021 16:32:52 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1623249172; 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=oTvJUNqNPXJgrATOUO5AJ0EllSZ5xLN85/3fQaACIhM=; b=ckclrrh8R2rjSCsIJOO3Gmdo5IV8CSqDWXGxCyOiLEGdOp8yE4bUSK2hliXNS5hrCdi1Xy KAjGylpJid/k5gR66MMg90X8SOLKxELW44ANk8UQEiE0CpB7nVsCJ1hs+p36f/1TnNO2Bq gPxBZguTtaQXHrH610B7eRQWEh+oDW4= Date: Wed, 9 Jun 2021 16:32:46 +0200 From: Borislav Petkov To: "Kuppuswamy, Sathyanarayanan" Cc: Peter Zijlstra , Andy Lutomirski , Dave Hansen , Tony Luck , Andi Kleen , Kirill Shutemov , Kuppuswamy Sathyanarayanan , Dan Williams , Raj Ashok , Sean Christopherson , linux-kernel@vger.kernel.org, Tom Lendacky Subject: Re: [RFC v2-fix-v2 1/1] x86: Introduce generic protected guest abstraction Message-ID: References: <20210527042356.3983284-2-sathyanarayanan.kuppuswamy@linux.intel.com> <20210601211417.2177598-1-sathyanarayanan.kuppuswamy@linux.intel.com> <82f9e5a9-682a-70be-e5ea-938bb742265f@linux.intel.com> <9466ae0b-3a2a-5a43-a4c6-39e07ebe0fbc@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <9466ae0b-3a2a-5a43-a4c6-39e07ebe0fbc@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 09, 2021 at 07:01:13AM -0700, Kuppuswamy, Sathyanarayanan wrote: > I am still not clear. What happens when a driver which includes > linux/protected-guest.h is compiled for non-x86 arch (s390 or arm64)? I was wondering what felt weird: why is prot{ected,}_guest_has() in a generic linux/ namespace header and not in an asm/ one? I think the proper way is for the other arches should be to provide their own prot_guest_has() implementation which generic code uses and the generic header would contain only the PR_GUEST_* defines. Take ioremap() as an example: arch/x86/include/asm/io.h arch/arm64/include/asm/io.h arch/s390/include/asm/io.h ... and pretty much every arch has that arch-specific io.h header which defines ioremap() and generic code includes include/linux/io.h which includes the respective asm/io.h header so that users can call the respective ioremap() implementation. prot_guest_has() sounds just the same to me. Better? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette