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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1354CC05027 for ; Fri, 10 Feb 2023 19:04:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233222AbjBJTED (ORCPT ); Fri, 10 Feb 2023 14:04:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50044 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232950AbjBJTD7 (ORCPT ); Fri, 10 Feb 2023 14:03:59 -0500 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA93C7B154; Fri, 10 Feb 2023 11:03:57 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (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 3D4811EC0742; Fri, 10 Feb 2023 20:03:56 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1676055836; 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=EnP7Qn9diKKpjwRuoGhPqOr/OsykyrWTSkMEQBnQXCM=; b=H2Czyoff1Sqh+ZjOS60TJUZN6VKpNA5+2HyOuVICdLM8kWfEXTdtSHy1Ikep7BBkNKSNjx IHK12hZerE6XPuz9WRklr4RXE0NMaLUCnDr73n7zoSsbwsVWp9gUbIp6quQryLcsuMLFw3 LgJyfgaZ10bGZnjDaw+MU2VSteKRGbI= Date: Fri, 10 Feb 2023 20:03:51 +0100 From: Borislav Petkov To: Sean Christopherson Cc: "Michael Kelley (LINUX)" , Dave Hansen , "hpa@zytor.com" , KY Srinivasan , Haiyang Zhang , "wei.liu@kernel.org" , Dexuan Cui , "luto@kernel.org" , "peterz@infradead.org" , "davem@davemloft.net" , "edumazet@google.com" , "kuba@kernel.org" , "pabeni@redhat.com" , "lpieralisi@kernel.org" , "robh@kernel.org" , "kw@linux.com" , "bhelgaas@google.com" , "arnd@arndb.de" , "hch@lst.de" , "m.szyprowski@samsung.com" , "robin.murphy@arm.com" , "thomas.lendacky@amd.com" , "brijesh.singh@amd.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "dave.hansen@linux.intel.com" , Tianyu Lan , "kirill.shutemov@linux.intel.com" , "sathyanarayanan.kuppuswamy@linux.intel.com" , "ak@linux.intel.com" , "isaku.yamahata@intel.com" , "dan.j.williams@intel.com" , "jane.chu@oracle.com" , "tony.luck@intel.com" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-pci@vger.kernel.org" , "linux-arch@vger.kernel.org" , "iommu@lists.linux.dev" Subject: Re: [PATCH v5 06/14] x86/ioremap: Support hypervisor specified range to map as encrypted Message-ID: References: <1673559753-94403-1-git-send-email-mikelley@microsoft.com> <1673559753-94403-7-git-send-email-mikelley@microsoft.com> <4216dea6-d899-aecb-2207-caa2ae7db0e3@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 10, 2023 at 06:41:54PM +0000, Sean Christopherson wrote: > Anyways, tying things back to the actual code being discussed, I vote against > CC_ATTR_PARAVISOR. Being able to trust device emulation is not unique to a > paravisor. A single flag also makes too many assumptions about what is trusted > and thus should be accessed encrypted. I'm not crazy about the alternative either: one flag per access type: IO APIC, vTPM, and soon. Soon this will become an unmaintainable zoo of different guest types people want the kernel to support. I don't think I want that madness in kernel proper. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette