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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 8204CC433FF for ; Mon, 5 Aug 2019 08:01:58 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 5A10F20818 for ; Mon, 5 Aug 2019 08:01:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="HX1IWoQi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A10F20818 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=vnkSQIIvXTj7pz5i//XRd/w0MOeNFi/7JmL8xOF1P8Q=; b=HX1IWoQiWkLK3+ CJkl8vtYTlzG/rnAO9oFUQ7HUVyIug6byzJ4Sn2J5d3xiV4V5A+VQSQiWsnr1E2C/SB/kyypVEdZZ pQLuWl13IC4LPYSv0nWxSgm0p4ONccvgA5tIQbio2GJA8i8UT6RlrvwPnqvXlNPIrgw+eOXATm98z ECzAly1Eny1PXl+TeiLviw5Fj5oLbtGSdv9YsJ8S/NXuc8iNl08jZHIQPa41J6HASLZi8zmvkNF6p 2RiBKBOzmGCfJUm2IcxVETKcjR/BitiV0ntnhvvflOcz5jwQghlFx7jw5ER5A4ZRRsUNJwGEyzMdH 7ZB4LArQk4mVsDenn1/w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1huXwG-0003MM-Fk; Mon, 05 Aug 2019 08:01:52 +0000 Received: from [195.167.85.94] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1huXwC-0003Lv-6m; Mon, 05 Aug 2019 08:01:49 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Subject: fix default dma_mmap_* pgprot v2 Date: Mon, 5 Aug 2019 11:01:43 +0300 Message-Id: <20190805080145.5694-1-hch@lst.de> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Shawn Anastasio , Will Deacon , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Russell King , linux-mips@vger.kernel.org, Paul Burton , Catalin Marinas , James Hogan , Robin Murphy , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi all, As Shawn pointed out we've had issues with the dma mmap pgprots ever since the dma_common_mmap helper was added beyong the initial architectures - we default to uncached mappings, but for devices that are DMA coherent, or if the DMA_ATTR_NON_CONSISTENT is set (and supported) this can lead to aliasing of cache attributes. This patch fixes that. My explanation of why this hasn't been much of an issue is that the dma_mmap_ helpers aren't used widely and mostly just in architecture specific drivers. Changes since v1: - fix handling of DMA_ATTR_NON_CONSISTENT where it is a no-op (which is most architectures) - remove DMA_ATTR_WRITE_COMBINE on mips, as it seem dangerous as-is _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel