Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756088AbdGCOSw (ORCPT ); Mon, 3 Jul 2017 10:18:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36838 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932584AbdGCNpT (ORCPT ); Mon, 3 Jul 2017 09:45:19 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefano Stabellini , Pooya Keshavarzi , Boris Ostrovsky , Konrad Rzeszutek Wilk , Sasha Levin Subject: [PATCH 4.9 083/172] swiotlb-xen: update dev_addr after swapping pages Date: Mon, 3 Jul 2017 15:34:23 +0200 Message-Id: <20170703133418.180425075@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170703133414.260777365@linuxfoundation.org> References: <20170703133414.260777365@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2208 Lines: 65 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefano Stabellini [ Upstream commit f1225ee4c8fcf09afaa199b8b1f0450f38b8cd11 ] In xen_swiotlb_map_page and xen_swiotlb_map_sg_attrs, if the original page is not suitable, we swap it for another page from the swiotlb pool. In these cases, we don't update the previously calculated dma address for the page before calling xen_dma_map_page. Thus, we end up calling xen_dma_map_page passing the wrong dev_addr, resulting in xen_dma_map_page mistakenly assuming that the page is foreign when it is local. Fix the bug by updating dev_addr appropriately. This change has no effect on x86, because xen_dma_map_page is a stub there. Signed-off-by: Stefano Stabellini Signed-off-by: Pooya Keshavarzi Tested-by: Pooya Keshavarzi Reviewed-by: Boris Ostrovsky Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/xen/swiotlb-xen.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -409,9 +409,9 @@ dma_addr_t xen_swiotlb_map_page(struct d if (map == SWIOTLB_MAP_ERROR) return DMA_ERROR_CODE; + dev_addr = xen_phys_to_bus(map); xen_dma_map_page(dev, pfn_to_page(map >> PAGE_SHIFT), dev_addr, map & ~PAGE_MASK, size, dir, attrs); - dev_addr = xen_phys_to_bus(map); /* * Ensure that the address returned is DMA'ble @@ -567,13 +567,14 @@ xen_swiotlb_map_sg_attrs(struct device * sg_dma_len(sgl) = 0; return 0; } + dev_addr = xen_phys_to_bus(map); xen_dma_map_page(hwdev, pfn_to_page(map >> PAGE_SHIFT), dev_addr, map & ~PAGE_MASK, sg->length, dir, attrs); - sg->dma_address = xen_phys_to_bus(map); + sg->dma_address = dev_addr; } else { /* we are not interested in the dma_addr returned by * xen_dma_map_page, only in the potential cache flushes executed