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 C7461C2D0E4 for ; Tue, 24 Nov 2020 09:01:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F49E2076B for ; Tue, 24 Nov 2020 09:01:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="fj3ptSS1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730940AbgKXJBD (ORCPT ); Tue, 24 Nov 2020 04:01:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726942AbgKXJBC (ORCPT ); Tue, 24 Nov 2020 04:01:02 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A22F1C0613CF for ; Tue, 24 Nov 2020 01:01:02 -0800 (PST) Received: from zn.tnic (p200300ec2f0e3600a9cb1df0e98d070c.dip0.t-ipconnect.de [IPv6:2003:ec:2f0e:3600:a9cb:1df0:e98d:70c]) (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 3EB881EC04DF; Tue, 24 Nov 2020 10:01:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1606208460; 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=spuCTuobFwZYtpYYd4DV2fwHDk1geO/8cruVmOCIaH0=; b=fj3ptSS1GtXsvj+p8OhlpnW/U9DSzWgcspkEvxrdmT29kMCqUlsSIez4hyxYY0SZw7LX/z 4yAaVBGc6siRwnUFXzcYgN4RqqvaO3Rmtt6RdnKKSSd40K8B+OPuBSjxCvic3UJo9603rU M62U9inbR4ckew8vrSFeasWEjqAIMoU= Date: Tue, 24 Nov 2020 10:00:55 +0100 From: Borislav Petkov To: Konrad Rzeszutek Wilk Cc: Ashish Kalra , hch@lst.de, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, luto@kernel.org, peterz@infradead.org, dave.hansen@linux-intel.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, brijesh.singh@amd.com, Thomas.Lendacky@amd.com, jon.grimm@amd.com, rientjes@google.com Subject: Re: [PATCH v6] swiotlb: Adjust SWIOTBL bounce buffer size for SEV guests. Message-ID: <20201124090055.GB4009@zn.tnic> References: <20201119214205.11062-1-Ashish.Kalra@amd.com> <20201123170647.GE15044@zn.tnic> <20201123175632.GA21539@char.us.oracle.com> <20201123180215.GG15044@zn.tnic> <20201123184327.GA22269@char.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201123184327.GA22269@char.us.oracle.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 23, 2020 at 01:43:27PM -0500, Konrad Rzeszutek Wilk wrote: > I am assuming that TDX is going to have the same exact issue that > AMD SEV will have. > > Are you recommending to have an unified x86 specific callback > where we check if it: > > - CPUID_AMD_SEV or CPUID_INTEL_TDX is set, and > - No vIOMMU present, then we adjust the size? I'm thinking do it correct right now and when TDX appears on the horizon requesting this adjusted to TDX, then change it. Like we always do. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette