Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757704Ab2JQTS1 (ORCPT ); Wed, 17 Oct 2012 15:18:27 -0400 Received: from terminus.zytor.com ([198.137.202.10]:36608 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757568Ab2JQTS0 (ORCPT ); Wed, 17 Oct 2012 15:18:26 -0400 Date: Wed, 17 Oct 2012 12:18:12 -0700 From: tip-bot for Daniel J Blueman Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, tglx@linutronix.de, hpa@linux.intel.com, borislav.petkov@amd.com, daniel@numascale-asia.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, hpa@linux.intel.com, daniel@numascale-asia.com, borislav.petkov@amd.com In-Reply-To: <1349073725-14093-1-git-send-email-daniel@numascale-asia.com> References: <1349073725-14093-1-git-send-email-daniel@numascale-asia.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86, amd, mce: Avoid NULL pointer reference on CPU northbridge lookup Git-Commit-ID: 21c5e50e15b1abd797e62f18fd7f90b9cc004cbd X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Wed, 17 Oct 2012 12:18:18 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2482 Lines: 65 Commit-ID: 21c5e50e15b1abd797e62f18fd7f90b9cc004cbd Gitweb: http://git.kernel.org/tip/21c5e50e15b1abd797e62f18fd7f90b9cc004cbd Author: Daniel J Blueman AuthorDate: Mon, 1 Oct 2012 14:42:05 +0800 Committer: H. Peter Anvin CommitDate: Wed, 17 Oct 2012 11:25:32 -0700 x86, amd, mce: Avoid NULL pointer reference on CPU northbridge lookup When booting on a federated multi-server system (NumaScale), the processor Northbridge lookup returns NULL; add guards to prevent this causing an oops. On those systems, the northbridge is accessed through MMIO and the "normal" northbridge enumeration in amd_nb.c doesn't work since we're generating the northbridge ID from the initial APIC ID and the last is not unique on those systems. Long story short, we end up without northbridge descriptors. Signed-off-by: Daniel J Blueman Cc: stable@vger.kernel.org # 3.6 Link: http://lkml.kernel.org/r/1349073725-14093-1-git-send-email-daniel@numascale-asia.com [ Boris: beef up commit message ] Signed-off-by: Borislav Petkov Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/mcheck/mce_amd.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index c4e916d..698b6ec 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -576,12 +576,10 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank) int err = 0; if (shared_bank[bank]) { - nb = node_to_amd_nb(amd_get_nb_id(cpu)); - WARN_ON(!nb); /* threshold descriptor already initialized on this node? */ - if (nb->bank4) { + if (nb && nb->bank4) { /* yes, use it */ b = nb->bank4; err = kobject_add(b->kobj, &dev->kobj, name); @@ -615,8 +613,10 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank) atomic_set(&b->cpus, 1); /* nb is already initialized, see above */ - WARN_ON(nb->bank4); - nb->bank4 = b; + if (nb) { + WARN_ON(nb->bank4); + nb->bank4 = b; + } } err = allocate_threshold_blocks(cpu, bank, 0, -- 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/