From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932904AbcHKQVx (ORCPT ); Thu, 11 Aug 2016 12:21:53 -0400 Received: from terminus.zytor.com ([198.137.202.10]:60184 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932826AbcHKQVu (ORCPT ); Thu, 11 Aug 2016 12:21:50 -0400 Date: Thu, 11 Aug 2016 09:21:08 -0700 From: tip-bot for Sebastian Andrzej Siewior Message-ID: Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, bigeasy@linutronix.de, peterz@infradead.org, hpa@zytor.com, labbott@redhat.com, tglx@linutronix.de, torvalds@linux-foundation.org Reply-To: hpa@zytor.com, labbott@redhat.com, tglx@linutronix.de, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, mingo@kernel.org, bigeasy@linutronix.de, peterz@infradead.org In-Reply-To: <1470924515-9444-1-git-send-email-bigeasy@linutronix.de> References: <1470924515-9444-1-git-send-email-bigeasy@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe() Git-Commit-ID: d52c0569bab4edc888832df44dc7ac28517134f6 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: d52c0569bab4edc888832df44dc7ac28517134f6 Gitweb: http://git.kernel.org/tip/d52c0569bab4edc888832df44dc7ac28517134f6 Author: Sebastian Andrzej Siewior AuthorDate: Thu, 11 Aug 2016 16:08:35 +0200 Committer: Ingo Molnar CommitDate: Thu, 11 Aug 2016 16:35:50 +0200 x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe() I made a mistake while converting the driver to the hotplug state machine and as a result x2apic_cluster_probe() was accessing cpus_in_cluster before allocating it. This patch fixes it by setting the cpumask after the allocation the memory succeeded. While at it, I marked two functions static which are only used within this file. Reported-by: Laura Abbott Signed-off-by: Sebastian Andrzej Siewior Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 6b2c28471de5 ("x86/x2apic: Convert to CPU hotplug state machine") Link: http://lkml.kernel.org/r/1470924515-9444-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic/x2apic_cluster.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c index 6368fa6..54f35d9 100644 --- a/arch/x86/kernel/apic/x2apic_cluster.c +++ b/arch/x86/kernel/apic/x2apic_cluster.c @@ -155,7 +155,7 @@ static void init_x2apic_ldr(void) /* * At CPU state changes, update the x2apic cluster sibling info. */ -int x2apic_prepare_cpu(unsigned int cpu) +static int x2apic_prepare_cpu(unsigned int cpu) { if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL)) return -ENOMEM; @@ -168,7 +168,7 @@ int x2apic_prepare_cpu(unsigned int cpu) return 0; } -int x2apic_dead_cpu(unsigned int this_cpu) +static int x2apic_dead_cpu(unsigned int this_cpu) { int cpu; @@ -186,13 +186,18 @@ int x2apic_dead_cpu(unsigned int this_cpu) static int x2apic_cluster_probe(void) { int cpu = smp_processor_id(); + int ret; if (!x2apic_mode) return 0; + ret = cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "X2APIC_PREPARE", + x2apic_prepare_cpu, x2apic_dead_cpu); + if (ret < 0) { + pr_err("Failed to register X2APIC_PREPARE\n"); + return 0; + } cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, cpu)); - cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "X2APIC_PREPARE", - x2apic_prepare_cpu, x2apic_dead_cpu); return 1; }