From 9879d0300bc4d0ecbacce7969b1712a8d205ebaf Mon Sep 17 00:00:00 2001 From: Anil Kumar Mamidala Date: Fri, 22 Apr 2016 12:42:51 +0530 Subject: qos: Register irq notify after adding the qos request Before adding the irq affinity based qos request to the list, if the affinity of the interrupt changes it will trigger notify call. This notifier call will try to update the qos request. Accessing the qos request which is not yet added to the list leads to a NULL pointer exception. Avoid this race by registering the notifier after adding the qos request. Change-Id: I99869cc233573b5db10e4f3224d65c29511050ea Signed-off-by: Anil Kumar Mamidala --- kernel/power/qos.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/kernel/power/qos.c b/kernel/power/qos.c index b822206ac811..582b66e882ce 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -596,7 +596,6 @@ void pm_qos_add_request(struct pm_qos_request *req, #ifdef CONFIG_SMP case PM_QOS_REQ_AFFINE_IRQ: if (irq_can_set_affinity(req->irq)) { - int ret = 0; struct irq_desc *desc = irq_to_desc(req->irq); struct cpumask *mask = desc->irq_data.common->affinity; @@ -606,13 +605,6 @@ void pm_qos_add_request(struct pm_qos_request *req, req->irq_notify.notify = pm_qos_irq_notify; req->irq_notify.release = pm_qos_irq_release; - ret = irq_set_affinity_notifier(req->irq, - &req->irq_notify); - if (ret) { - WARN(1, KERN_ERR "IRQ affinity notify set failed\n"); - req->type = PM_QOS_REQ_ALL_CORES; - cpumask_setall(&req->cpus_affine); - } } else { req->type = PM_QOS_REQ_ALL_CORES; cpumask_setall(&req->cpus_affine); @@ -634,6 +626,24 @@ void pm_qos_add_request(struct pm_qos_request *req, trace_pm_qos_add_request(pm_qos_class, value); pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints, req, PM_QOS_ADD_REQ, value); + +#ifdef CONFIG_SMP + if (req->type == PM_QOS_REQ_AFFINE_IRQ && + irq_can_set_affinity(req->irq)) { + int ret = 0; + + ret = irq_set_affinity_notifier(req->irq, + &req->irq_notify); + if (ret) { + WARN(1, "IRQ affinity notify set failed\n"); + req->type = PM_QOS_REQ_ALL_CORES; + cpumask_setall(&req->cpus_affine); + pm_qos_update_target( + pm_qos_array[pm_qos_class]->constraints, + req, PM_QOS_UPDATE_REQ, value); + } + } +#endif } EXPORT_SYMBOL_GPL(pm_qos_add_request); -- cgit v1.2.3