From patchwork Fri Aug 14 14:41:06 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 507398 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id DB693140291 for ; Sat, 15 Aug 2015 00:42:01 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755006AbbHNOlS (ORCPT ); Fri, 14 Aug 2015 10:41:18 -0400 Received: from foss.arm.com ([217.140.101.70]:38635 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755280AbbHNOlR (ORCPT ); Fri, 14 Aug 2015 10:41:17 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 30DB747D; Fri, 14 Aug 2015 07:41:12 -0700 (PDT) Received: from approximate.cambridge.arm.com (approximate.cambridge.arm.com [10.1.209.148]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BE5163F5A0; Fri, 14 Aug 2015 07:41:14 -0700 (PDT) From: Marc Zyngier To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Will Deacon , Bjorn Helgaas , Suravee Suthikulpanit , Lorenzo Pieralisi Cc: Alexander Graf , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org Subject: [PATCH 1/3] PCI: pci-host-generic: Fix lookup of linux, pci-probe-only property Date: Fri, 14 Aug 2015 15:41:06 +0100 Message-Id: <1439563268-13418-2-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1439563268-13418-1-git-send-email-marc.zyngier@arm.com> References: <1439563268-13418-1-git-send-email-marc.zyngier@arm.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When pci-host-generic looks for the probe-only property, it seems to trust the DT to be correctly written, and assumes that there is a parameter to the property. Unfortunately, this is not always the case, and some firmware expose this property naked. The driver ends up making a decision based on whatever the property pointer points to, which is likely to be junk. Instead, let's check for the validity of the property, and ignore it if the firmware couldn't make up its mind. Signed-off-by: Marc Zyngier --- drivers/pci/host/pci-host-generic.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c index 265dd25..2b2e2ff 100644 --- a/drivers/pci/host/pci-host-generic.c +++ b/drivers/pci/host/pci-host-generic.c @@ -211,6 +211,7 @@ static int gen_pci_probe(struct platform_device *pdev) const char *type; const struct of_device_id *of_id; const int *prop; + int len; struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL); @@ -225,12 +226,16 @@ static int gen_pci_probe(struct platform_device *pdev) return -EINVAL; } - prop = of_get_property(of_chosen, "linux,pci-probe-only", NULL); + prop = of_get_property(of_chosen, "linux,pci-probe-only", &len); if (prop) { - if (*prop) - pci_add_flags(PCI_PROBE_ONLY); - else - pci_clear_flags(PCI_PROBE_ONLY); + if (len) { + if (be32_to_cpup(prop)) + pci_add_flags(PCI_PROBE_ONLY); + else + pci_clear_flags(PCI_PROBE_ONLY); + } else { + dev_warn(&pdev->dev, "linux,pci-probe-only set without value, ignoring\n"); + } } of_id = of_match_node(gen_pci_of_match, np);