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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CC2DC433EF for ; Thu, 30 Sep 2021 01:30:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0715A617E2 for ; Thu, 30 Sep 2021 01:30:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347453AbhI3Bcc (ORCPT ); Wed, 29 Sep 2021 21:32:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:58350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbhI3Bcb (ORCPT ); Wed, 29 Sep 2021 21:32:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2260F615A4; Thu, 30 Sep 2021 01:30:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1632965449; bh=wbV6F8K1YktqcMeI72zuNPMPZDIFwa82A8AaD7ODLuw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fXjfarfg3fUv2muoaPe42X68dGkHzYxP7+Rx+dfcEIwPVEEXYb3YujSrGkuwYaEyR RBviPEQVigL46cTnV30o1q9UuVwTnlEwM80bxFwI0dOYDPqd5h7OeNGds+KwCdHbth aNRhbH1JLXBtYJx+1W0V35Y7MM53cDmE0dhYqLU+DoKzLo9As2V6bZ62L1VPBx0oeB TpDkkGOxFvmsRoFajPHO+DBJGWr3puqmzrHfMTxvzzZXwnPUNwr3MxrXFqkgyrJk4J 4Lxnxb5c3SAbWRdBXITuXM7EnTl92PVstb9AIKyQn9fbKOLR2V3j1XNg6flwXR2eTU t0TgXntvfJYTw== From: Mike Rapoport To: linux-arm-kernel@lists.infradead.org Cc: Alex Bee , Andrew Morton , Anshuman Khandual , Catalin Marinas , Christoph Hellwig , David Hildenbrand , Linux Kernel Mailing List , Marek Szyprowski , Mike Rapoport , Mike Rapoport , Robin Murphy , Will Deacon , iommu@lists.linux-foundation.org Subject: [PATCH 1/2] dma-mapping: remove bogus test for pfn_valid from dma_map_resource Date: Thu, 30 Sep 2021 04:30:38 +0300 Message-Id: <20210930013039.11260-2-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20210930013039.11260-1-rppt@kernel.org> References: <20210930013039.11260-1-rppt@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Rapoport dma_map_resource() uses pfn_valid() to ensure the range is not RAM. However, pfn_valid() only checks for availability of the memory map for a PFN but it does not ensure that the PFN is actually backed by RAM. As dma_map_resource() is the only method in DMA mapping APIs that has this check, simply drop the pfn_valid() test from dma_map_resource(). Link: https://lore.kernel.org/all/20210824173741.GC623@arm.com/ Signed-off-by: Mike Rapoport --- kernel/dma/mapping.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 06fec5547e7c..dda8d8b84a55 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -296,10 +296,6 @@ dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr, if (WARN_ON_ONCE(!dev->dma_mask)) return DMA_MAPPING_ERROR; - /* Don't allow RAM to be mapped */ - if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) - return DMA_MAPPING_ERROR; - if (dma_map_direct(dev, ops)) addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs); else if (ops->map_resource) -- 2.28.0