Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755402AbbHNOlX (ORCPT ); Fri, 14 Aug 2015 10:41:23 -0400 Received: from foss.arm.com ([217.140.101.70]:38648 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755280AbbHNOlT (ORCPT ); Fri, 14 Aug 2015 10:41:19 -0400 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 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> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1794 Lines: 55 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"); + } } } } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/