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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 EA646C43441 for ; Wed, 21 Nov 2018 16:01:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BBA49214DA for ; Wed, 21 Nov 2018 16:01:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBA49214DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731627AbeKVCgB (ORCPT ); Wed, 21 Nov 2018 21:36:01 -0500 Received: from foss.arm.com ([217.140.101.70]:53644 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730072AbeKVCgA (ORCPT ); Wed, 21 Nov 2018 21:36:00 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0034E3616; Wed, 21 Nov 2018 08:01:00 -0800 (PST) Received: from e110467-lin.cambridge.arm.com (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 71AEE3F5CF; Wed, 21 Nov 2018 08:00:58 -0800 (PST) From: Robin Murphy To: hch@lst.de, konrad.wilk@oracle.com Cc: m.szyprowski@samsung.com, john.stultz@linaro.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, sstabellini@kernel.org Subject: [PATCH v2 2/2] swiotlb: Skip cache maintenance on map error Date: Wed, 21 Nov 2018 16:00:51 +0000 Message-Id: X-Mailer: git-send-email 2.19.1.dirty In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If swiotlb_bounce_page() failed, calling arch_sync_dma_for_device() may lead to such delights as performing cache maintenance on whatever address phys_to_virt(SWIOTLB_MAP_ERROR) looks like, which is typically outside the kernel memory map and goes about as well as expected. Don't do that. Fixes: a4a4330db46a ("swiotlb: add support for non-coherent DMA") Tested-by: John Stultz Reviewed-by: Christoph Hellwig Signed-off-by: Robin Murphy --- v2: Collect tags kernel/dma/swiotlb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 5731daa09a32..045930e32c0e 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -679,7 +679,8 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, } if (!dev_is_dma_coherent(dev) && - (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) + (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0 && + dev_addr != DIRECT_MAPPING_ERROR) arch_sync_dma_for_device(dev, phys, size, dir); return dev_addr; -- 2.19.1.dirty