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: 7015521 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 99407C05AC for ; Fri, 14 Aug 2015 14:41:51 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D1F0C207D2 for ; Fri, 14 Aug 2015 14:41:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D95B1207F9 for ; Fri, 14 Aug 2015 14:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755380AbbHNOlU (ORCPT ); Fri, 14 Aug 2015 10:41:20 -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 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 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-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable 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 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"); + } } } }