diff options
| author | Toshi Kani <toshi.kani@hp.com> | 2013-08-29 18:22:07 -0600 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-09-25 10:38:09 +0200 |
| commit | 574b851e99923c884fee4e0d7cf7e7c3dc023ffa (patch) | |
| tree | 7498d2dcbc4bd2e3bf03434461ca36d31790a087 | |
| parent | f6913f990273a1fbfc0ec501d4998faa4f1ebae6 (diff) | |
hotplug / x86: Add hotplug lock to missing places
lock_device_hotplug[_sysfs]() 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 <toshi.kani@hp.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | arch/x86/kernel/topology.c | 2 | ||||
| -rw-r--r-- | drivers/base/cpu.c | 24 |
2 files changed, 24 insertions, 2 deletions
diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index 5823bbd668f4..a3f35ebb3b52 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 848ebbd25717..51f5d7fe2f0b 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -93,7 +93,17 @@ static ssize_t cpu_probe_store(struct device *dev, const char *buf, size_t count) { - return arch_cpu_probe(buf, count); + ssize_t cnt; + int ret; + + ret = lock_device_hotplug_sysfs(); + if (ret) + return ret; + + cnt = arch_cpu_probe(buf, count); + + unlock_device_hotplug(); + return cnt; } static ssize_t cpu_release_store(struct device *dev, @@ -101,7 +111,17 @@ static ssize_t cpu_release_store(struct device *dev, const char *buf, size_t count) { - return arch_cpu_release(buf, count); + ssize_t cnt; + int ret; + + ret = lock_device_hotplug_sysfs(); + if (ret) + return ret; + + cnt = arch_cpu_release(buf, count); + + unlock_device_hotplug(); + return cnt; } static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store); |