From patchwork Fri Sep 4 14:09:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 11757375 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 716AA618 for ; Fri, 4 Sep 2020 14:10:35 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 298C6206B7 for ; Fri, 4 Sep 2020 14:10:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="A5pq+QXz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 298C6206B7 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-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=blzCDBMhoaXZkBUk/GbZEhVEYtJOD5NgwRq4PU5uW/Y=; b=A5pq+QXzHQ5O7bvDmt8Mkj0sf4 c0pdiMrWA7vZLVlwrELXWFqGhPZyk+BKwSrU+HNmP90bQ4xpMP04uXMeNth4UBUPuX/l9IeCBHOZG TfIW6wJJSneh3TdZNqPDOYXUHkfl/2GdM93mThOxmKuDSX9ZMLRoRO2BN95FLjMPNYbcFB8yqz5/J k+dwbye1sAvSQYAC1sctgkA7hm6Ez1e0m13bB4lx3UVZA7cnflBRikT4vrhciEdjDe4+Ur83NqyOV 6eXplhdMLUKjHBe4BPgKam/sF6H6lJg2kThRQD7i9866GnMIOldT6Q+VNVVICeVwKGvqC1n/VsOcY mGMqCQDw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kECP2-0006rC-2I; Fri, 04 Sep 2020 14:09:20 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kECOz-0006qR-2q for linux-arm-kernel@lists.infradead.org; Fri, 04 Sep 2020 14:09:17 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 588711045; Fri, 4 Sep 2020 07:09:14 -0700 (PDT) Received: from red-moon.arm.com (unknown [10.57.6.237]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 43D123F71F; Fri, 4 Sep 2020 07:09:13 -0700 (PDT) From: Lorenzo Pieralisi To: linux-pci@vger.kernel.org Subject: [PATCH] PCI: rockchip: Fix bus checks in rockchip_pcie_valid_device() Date: Fri, 4 Sep 2020 15:09:04 +0100 Message-Id: <20200904140904.944-1-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 2.26.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200904_100917_169634_B48BB45D X-CRM114-Status: GOOD ( 15.93 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rob Herring , Lorenzo Pieralisi , Samuel Dionne-Riel , Shawn Lin , Bjorn Helgaas , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The root bus checks rework in: commit d84c572de1a3 ("PCI: rockchip: Use pci_is_root_bus() to check if bus is root bus") caused a regression whereby in rockchip_pcie_valid_device() if the bus parameter is the root bus and the dev value == 0 the function should return 1 (ie true) without checking if the bus->parent pointer is a root bus because that triggers a NULL pointer dereference. Fix this by streamlining the root bus detection. Fixes: d84c572de1a3 ("PCI: rockchip: Use pci_is_root_bus() to check if bus is root bus") Reported-by: Samuel Dionne-Riel Signed-off-by: Lorenzo Pieralisi Cc: Bjorn Helgaas Cc: Rob Herring Cc: Shawn Lin Reviewed-by: Rob Herring --- drivers/pci/controller/pcie-rockchip-host.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/pci/controller/pcie-rockchip-host.c b/drivers/pci/controller/pcie-rockchip-host.c index 0bb2fb3e8a0b..9705059523a6 100644 --- a/drivers/pci/controller/pcie-rockchip-host.c +++ b/drivers/pci/controller/pcie-rockchip-host.c @@ -71,16 +71,13 @@ static void rockchip_pcie_update_txcredit_mui(struct rockchip_pcie *rockchip) static int rockchip_pcie_valid_device(struct rockchip_pcie *rockchip, struct pci_bus *bus, int dev) { - /* access only one slot on each root port */ - if (pci_is_root_bus(bus) && dev > 0) - return 0; - /* - * do not read more than one device on the bus directly attached + * Access only one slot on each root port. + * Do not read more than one device on the bus directly attached * to RC's downstream side. */ - if (pci_is_root_bus(bus->parent) && dev > 0) - return 0; + if (pci_is_root_bus(bus) || pci_is_root_bus(bus->parent)) + return dev == 0; return 1; }