Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754714Ab3HQTtA (ORCPT ); Sat, 17 Aug 2013 15:49:00 -0400 Received: from g6t0187.atlanta.hp.com ([15.193.32.64]:17298 "EHLO g6t0187.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754656Ab3HQTs5 (ORCPT ); Sat, 17 Aug 2013 15:48:57 -0400 From: Toshi Kani To: mingo@redhat.com, hpa@linux.intel.com, tglx@linutronix.de, gregkh@linuxfoundation.org, benh@kernel.crashing.org Cc: x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, rjw@sisk.pl, fenghua.yu@intel.com, bp@suse.de, srivatsa.bhat@linux.vnet.ibm.com, isimatu.yasuaki@jp.fujitsu.com, Toshi Kani Subject: [PATCH 2/4] hotplug, x86: Add hotplug lock to missing places Date: Sat, 17 Aug 2013 13:46:57 -0600 Message-Id: <1376768819-28975-3-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1376768819-28975-1-git-send-email-toshi.kani@hp.com> References: <1376768819-28975-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2251 Lines: 76 lock_device_hotplug() serializes CPU & Memory online/offline and hotplug operations. However, this lock is not held in the debug interfaces below that initiate CPU online/offline operations. - _debug_hotplug_cpu(), cpu0 hotplug test interface enabled by CONFIG_DEBUG_HOTPLUG_CPU0. - cpu_probe_store() and cpu_release_store(), cpu hotplug test interface enabled by CONFIG_ARCH_CPU_PROBE_RELEASE. This patch changes the above interfaces to hold lock_device_hotplug(). Signed-off-by: Toshi Kani --- arch/x86/kernel/topology.c | 2 ++ drivers/base/cpu.c | 16 ++++++++++++++-- 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index 5823bbd..a3f35eb 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -65,6 +65,7 @@ int __ref _debug_hotplug_cpu(int cpu, int action) if (!cpu_is_hotpluggable(cpu)) return -EINVAL; + lock_device_hotplug(); cpu_hotplug_driver_lock(); switch (action) { @@ -91,6 +92,7 @@ int __ref _debug_hotplug_cpu(int cpu, int action) } cpu_hotplug_driver_unlock(); + unlock_device_hotplug(); return ret; } diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 4c358bc..4cc6928 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -88,7 +88,13 @@ static ssize_t cpu_probe_store(struct device *dev, const char *buf, size_t count) { - return arch_cpu_probe(buf, count); + ssize_t ret; + + lock_device_hotplug(); + ret = arch_cpu_probe(buf, count); + unlock_device_hotplug(); + + return ret; } static ssize_t cpu_release_store(struct device *dev, @@ -96,7 +102,13 @@ static ssize_t cpu_release_store(struct device *dev, const char *buf, size_t count) { - return arch_cpu_release(buf, count); + ssize_t ret; + + lock_device_hotplug(); + ret = arch_cpu_release(buf, count); + unlock_device_hotplug(); + + return ret; } static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store); -- 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/