From 7bed1b3caaedd5918f0820b29f3b7a2ddc812922 Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Tue, 24 Sep 2013 11:05:16 -0700 Subject: Thermal: x86_pkg_temp: change spin lock x86_pkg_temp receives thermal notifications via a callback from a therm_throt driver, where thermal interrupts are processed. This callback is pkg_temp_thermal_platform_thermal_notify. Here to avoid multiple interrupts from cores in a package, we disable the source and also set a variable to avoid scheduling delayed work function. This variable is protected via spin_lock_irqsave. On one buggy platform, we still receiving interrupts even if the source is disabled. This can cause deadlock/lockdep warning, when interrupt is generated while under spinlock in work function. Change spin_lock to spin_lock_irqsave and spin_unlock to spin_unlock_irqrestore as the data it is trying to protect can also be modified in a notification call called from interrupt handler. Signed-off-by: Srinivas Pandruvada Signed-off-by: Zhang Rui --- drivers/thermal/x86_pkg_temp_thermal.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'drivers/thermal') diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c index f36950e4134f..7722cb9d5a80 100644 --- a/drivers/thermal/x86_pkg_temp_thermal.c +++ b/drivers/thermal/x86_pkg_temp_thermal.c @@ -316,18 +316,19 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work) int phy_id = topology_physical_package_id(cpu); struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); bool notify = false; + unsigned long flags; if (!phdev) return; - spin_lock(&pkg_work_lock); + spin_lock_irqsave(&pkg_work_lock, flags); ++pkg_work_cnt; if (unlikely(phy_id > max_phy_id)) { - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); return; } pkg_work_scheduled[phy_id] = 0; - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); enable_pkg_thres_interrupt(); rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val); @@ -397,6 +398,7 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) int thres_count; u32 eax, ebx, ecx, edx; u8 *temp; + unsigned long flags; cpuid(6, &eax, &ebx, &ecx, &edx); thres_count = ebx & 0x07; @@ -420,19 +422,19 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) goto err_ret_unlock; } - spin_lock(&pkg_work_lock); + spin_lock_irqsave(&pkg_work_lock, flags); if (topology_physical_package_id(cpu) > max_phy_id) max_phy_id = topology_physical_package_id(cpu); temp = krealloc(pkg_work_scheduled, (max_phy_id+1) * sizeof(u8), GFP_ATOMIC); if (!temp) { - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); err = -ENOMEM; goto err_ret_free; } pkg_work_scheduled = temp; pkg_work_scheduled[topology_physical_package_id(cpu)] = 0; - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu); phy_dev_entry->first_cpu = cpu; -- cgit v1.2.1