From patchwork Fri Aug 14 14:41:07 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 507466 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id B46361401DE for ; Sat, 15 Aug 2015 01:27:23 +1000 (AEST) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 9AC6B1A1D97 for ; Sat, 15 Aug 2015 01:27:23 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by lists.ozlabs.org (Postfix) with ESMTP id DDC2D1A009B for ; Sat, 15 Aug 2015 00:41:19 +1000 (AEST) 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 81EA2483; Fri, 14 Aug 2015 07:41:14 -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 19A193F5A0; Fri, 14 Aug 2015 07:41:16 -0700 (PDT) From: Marc Zyngier To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Will Deacon , Bjorn Helgaas , Suravee Suthikulpanit , Lorenzo Pieralisi Subject: [PATCH 2/3] powerpc: PCI: Fix lookup of linux, pci-probe-only property Date: Fri, 14 Aug 2015 15:41:07 +0100 Message-Id: <1439563268-13418-3-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> X-Mailman-Approved-At: Sat, 15 Aug 2015 01:23:59 +1000 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Alexander Graf , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" When find_and_init_phbs() looks for the probe-only property, it seems to trust the firmware to be correctly written, and assumes that there is a parameter to the property. It is conceivable that the firmware could not be that perfect, and it could expose this property naked (at least one arm64 platform seems to exhibit this exact behaviour). The setup code the 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 --- arch/powerpc/platforms/pseries/setup.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index df6a704..6bdc1f9 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -490,14 +490,19 @@ static void __init find_and_init_phbs(void) */ if (of_chosen) { const int *prop; + int len; prop = of_get_property(of_chosen, - "linux,pci-probe-only", NULL); + "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 { + pr_warn("linux,pci-probe-only set without value, ignoring\n"); + } } } }