From 51e3c1b558b31b11bf5fc66d3c6f5adacf3573f7 Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Fri, 20 Aug 2010 10:36:34 +0300 Subject: [PATCH] x86, hwmon: Fix unsafe smp_processor_id() in thermal_throttle_add_dev Fix BUG: using smp_processor_id() in preemptible thermal_throttle_add_dev. We know the cpu number when calling thermal_throttle_add_dev, so we can remove smp_processor_id call in thermal_throttle_add_dev by supplying the cpu number as argument. This should resolve kernel bugzilla 16615/16629. Signed-off-by: Sergey Senozhatsky LKML-Reference: <20100820073634.GB5209@swordfish.minsk.epam.com> Cc: Fenghua Yu Cc: Joerg Roedel Cc: Maciej Rutecki Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/mcheck/therm_throt.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c index c2a8b26..d9368ee 100644 --- a/arch/x86/kernel/cpu/mcheck/therm_throt.c +++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c @@ -202,10 +202,11 @@ static int therm_throt_process(bool new_event, int event, int level) #ifdef CONFIG_SYSFS /* Add/Remove thermal_throttle interface for CPU device: */ -static __cpuinit int thermal_throttle_add_dev(struct sys_device *sys_dev) +static __cpuinit int thermal_throttle_add_dev(struct sys_device *sys_dev, + unsigned int cpu) { int err; - struct cpuinfo_x86 *c = &cpu_data(smp_processor_id()); + struct cpuinfo_x86 *c = &cpu_data(cpu); err = sysfs_create_group(&sys_dev->kobj, &thermal_attr_group); if (err) @@ -251,7 +252,7 @@ thermal_throttle_cpu_callback(struct notifier_block *nfb, case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: mutex_lock(&therm_cpu_lock); - err = thermal_throttle_add_dev(sys_dev); + err = thermal_throttle_add_dev(sys_dev, cpu); mutex_unlock(&therm_cpu_lock); WARN_ON(err); break; @@ -287,7 +288,7 @@ static __init int thermal_throttle_init_device(void) #endif /* connect live CPUs to sysfs */ for_each_online_cpu(cpu) { - err = thermal_throttle_add_dev(get_cpu_sysdev(cpu)); + err = thermal_throttle_add_dev(get_cpu_sysdev(cpu), cpu); WARN_ON(err); } #ifdef CONFIG_HOTPLUG_CPU -- 2.7.4