From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423183AbeE1MJK (ORCPT ); Mon, 28 May 2018 08:09:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:51990 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1165032AbeE1LEu (ORCPT ); Mon, 28 May 2018 07:04:50 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Jin , John Sobecki , Rzeszutek Wilk Subject: [PATCH 4.16 022/272] xen-swiotlb: fix the check condition for xen_swiotlb_free_coherent Date: Mon, 28 May 2018 12:00:55 +0200 Message-Id: <20180528100242.322563496@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180528100240.256525891@linuxfoundation.org> References: <20180528100240.256525891@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joe Jin commit 4855c92dbb7b3b85c23e88ab7ca04f99b9677b41 upstream. When run raidconfig from Dom0 we found that the Xen DMA heap is reduced, but Dom Heap is increased by the same size. Tracing raidconfig we found that the related ioctl() in megaraid_sas will call dma_alloc_coherent() to apply memory. If the memory allocated by Dom0 is not in the DMA area, it will exchange memory with Xen to meet the requiment. Later drivers call dma_free_coherent() to free the memory, on xen_swiotlb_free_coherent() the check condition (dev_addr + size - 1 <= dma_mask) is always false, it prevents calling xen_destroy_contiguous_region() to return the memory to the Xen DMA heap. This issue introduced by commit 6810df88dcfc2 "xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs.". Signed-off-by: Joe Jin Tested-by: John Sobecki Reviewed-by: Rzeszutek Wilk Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- drivers/xen/swiotlb-xen.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -365,7 +365,7 @@ xen_swiotlb_free_coherent(struct device * physical address */ phys = xen_bus_to_phys(dev_addr); - if (((dev_addr + size - 1 > dma_mask)) || + if (((dev_addr + size - 1 <= dma_mask)) || range_straddles_page_boundary(phys, size)) xen_destroy_contiguous_region(phys, order);