From patchwork Mon Jul 27 12:29:00 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King X-Patchwork-Id: 6873241 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 8C4A89F358 for ; Mon, 27 Jul 2015 12:31:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A9FD020623 for ; Mon, 27 Jul 2015 12:31:25 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D3A1920619 for ; Mon, 27 Jul 2015 12:31:24 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZJhXH-0002v7-6O; Mon, 27 Jul 2015 12:29:39 +0000 Received: from pandora.arm.linux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZJhX5-0002bt-4P for linux-arm-kernel@lists.infradead.org; Mon, 27 Jul 2015 12:29:28 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arm.linux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type:Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References:In-Reply-To; bh=spAwIUzXWL5MKNrjwQ0l1TVo8GRC9/H4vTeh2bt+3h8=; b=hAV9wISTin3ps4806ZUaDqb1QxCKsUYuPUuJOjMSQOv/aUH1NLZJebdnxECRVPoVzVWLTZToJmvVtKRbZ5bGimRBrHmWu0NYa78mzFon+98wqckqyxDoGS3O1iJXozeglS44qWN+HKP9m8Xhu83rHBMeR0lTPJNPejWMGbw/4nM=; Received: from e0022681537dd.dyn.arm.linux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:40251 helo=rmk-PC.arm.linux.org.uk) by pandora.arm.linux.org.uk with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1ZJhWf-0006zM-Od; Mon, 27 Jul 2015 13:29:01 +0100 Received: from rmk by rmk-PC.arm.linux.org.uk with local (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1ZJhWe-00043f-KS; Mon, 27 Jul 2015 13:29:00 +0100 In-Reply-To: <20150727122824.GH7557@n2100.arm.linux.org.uk> References: <20150727122824.GH7557@n2100.arm.linux.org.uk> From: Russell King To: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org Subject: [PATCH 03/18] iommu: tegra-smmu: fix iova_to_phys() method MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Mon, 27 Jul 2015 13:29:00 +0100 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150727_052928_134313_C64BC7D8 X-CRM114-Status: GOOD ( 11.52 ) X-Spam-Score: -2.0 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexandre Courbot , Joerg Roedel , Stephen Warren , Thierry Reding , Hiroshi Doyu Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP iova_to_phys() has several problems: (a) iova_to_phys() is supposed to return 0 if there is no entry present for the iova. (b) if as_get_pte() fails, we oops the kernel by dereferencing a NULL pointer. Really, we should not even be trying to allocate a page table at all, but should only be returning the presence of the 2nd level page table. This will be fixed in a subsequent patch. Treat both of these conditions as "no mapping" conditions. Signed-off-by: Russell King --- drivers/iommu/tegra-smmu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index c1f2e521dc52..083354903a1a 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -592,6 +592,9 @@ static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain, u32 *pte; pte = as_get_pte(as, iova, &page); + if (!pte || !*pte) + return 0; + pfn = *pte & as->smmu->pfn_mask; return PFN_PHYS(pfn);