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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 8EFFCC432C0 for ; Thu, 28 Nov 2019 15:36:57 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5AB7D2084D for ; Thu, 28 Nov 2019 15:36:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5AB7D2084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 1980E86132; Thu, 28 Nov 2019 15:36:57 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DPAIV9G0y0nv; Thu, 28 Nov 2019 15:36:54 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 5D207860BC; Thu, 28 Nov 2019 15:36:54 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 416E5C1DD5; Thu, 28 Nov 2019 15:36:54 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 931DBC0881 for ; Thu, 28 Nov 2019 15:36:52 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 7DF2686A35 for ; Thu, 28 Nov 2019 15:36:52 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xH4ICPKBGh0b for ; Thu, 28 Nov 2019 15:36:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 2BC8786A2D for ; Thu, 28 Nov 2019 15:36:51 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 5692068B05; Thu, 28 Nov 2019 16:36:46 +0100 (CET) Date: Thu, 28 Nov 2019 16:36:46 +0100 From: "hch@lst.de" To: Thomas Hellstrom Subject: Re: [PATCH 2/2] dma-mapping: force unencryped devices are always addressing limited Message-ID: <20191128153646.GA29430@lst.de> References: <20191127144006.25998-1-hch@lst.de> <20191127144006.25998-3-hch@lst.de> <20191128075153.GD20659@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: "thomas.lendacky@amd.com" , Konrad Rzeszutek Wilk , "linux-kernel@vger.kernel.org" , "hch@lst.de" , "linux-mm@kvack.org" , "iommu@lists.linux-foundation.org" , "christian.koenig@amd.com" X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Thu, Nov 28, 2019 at 08:02:16AM +0000, Thomas Hellstrom wrote: > > We have a hard time handling that in generic code. Do we have any > > good use case for SWIOTLB_FORCE not that we have force_dma_unencrypted? > > I'd love to be able to get rid of it.. > > > IIRC the justification for it is debugging. Drivers that don't do > syncing correctly or have incorrect assumptions of initialization of DMA > memory will not work properly when SWIOTLB is forced. We recently found > a vmw_pvscsi device flaw that way... Ok. I guess debugging is reasonable. Although that means I need to repsin this quite a bit as I now need a callout to dma_direct. I'll respin it in the next days. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu