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=-3.9 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 96A9AC388F9 for ; Tue, 27 Oct 2020 08:44:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F23B2224E for ; Tue, 27 Oct 2020 08:44:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uwVkm9dZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2509213AbgJ0IoY (ORCPT ); Tue, 27 Oct 2020 04:44:24 -0400 Received: from casper.infradead.org ([90.155.50.34]:34702 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2443713AbgJ0IoX (ORCPT ); Tue, 27 Oct 2020 04:44:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jmNJLBRCFdFXQCPDsbgJxCeg7OTT63Ved9ZS239LUkg=; b=uwVkm9dZG6qemWi1SUFtrghO8y U61seC3CjXBZ7FVApPCnMiEXJCSFrO9lQKMTHYIfUr9Y15LQGLCcbwOtZCWWC+SkmG8RD3nregZlH kiitudLOmiKoSMDkcfFvPQb6jgNt7RT75k+oQZNyu0kdR4f2Y5/Vde5PI0ld2a3pmmW/WyqruPh2z T8hXR7Pv6ajnvlYC45xSGFziuYv/skTWwThqP5D7d4RiekvuZst5EbXOyMB9/C6jF5mLzW6eym5ay +pvcFFcjgZ3QmJBlfJk+JydPksRC3QWLCdZGY6t3YUAhA1biP76jRuDxsqf5e10JjDNtZKhKTEWJw sXCX+sHg==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kXKaD-0002zC-6S; Tue, 27 Oct 2020 08:43:57 +0000 Date: Tue, 27 Oct 2020 08:43:57 +0000 From: Christoph Hellwig To: Jason Gunthorpe Cc: Tom Lendacky , x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, Radim Kr??m???? , Arnd Bergmann , Matt Fleming , Konrad Rzeszutek Wilk , Andrey Ryabinin , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , Alexander Potapenko , Thomas Gleixner , Dmitry Vyukov , Rik van Riel , Larry Woodman , Dave Young , Toshimitsu Kani , "Michael S. Tsirkin" , Brijesh Singh Subject: Re: AMD SME encrpytion and PCI BAR pages to user space Message-ID: <20201027084357.GA10053@infradead.org> References: <20201019152556.GA560082@nvidia.com> <4b9f13bf-3f82-1aed-c7be-0eaecebc5d82@amd.com> <20201021115933.GS6219@nvidia.com> <20201021160322.GT6219@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201021160322.GT6219@nvidia.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 21, 2020 at 01:03:22PM -0300, Jason Gunthorpe wrote: > Oh, interesting.. Yes the issue is no userspace DMA stuff uses the DMA > API correctly (because it is in userspace) > > So SWIOTLB tricks don't work, I wish the dma_map could fail for these > situations Userspace DMA by definition also does not use dma_map..