From 8660cb6674877d07792c78becd649af95f4df80d Mon Sep 17 00:00:00 2001 From: Anil Kumar Mamidala Date: Fri, 22 Apr 2016 12:42:51 +0530 Subject: [PATCH] ANDROID: GKI: 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. Test: build, boot Bug: 150901210 Change-Id: I99869cc233573b5db10e4f3224d65c29511050ea Signed-off-by: Anil Kumar Mamidala (cherry picked from commit 5db62557cb0e0fb88a638bd300295d1adb8f5bd7) Signed-off-by: Hridya Valsaraju --- kernel/power/qos.c | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 278cb0e6217a..789dd20b6669 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -574,9 +574,13 @@ 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; + struct cpumask *mask; + + if (!desc) + return; + + mask = desc->irq_data.common->affinity; /* Get the current affinity */ cpumask_copy(&req->cpus_affine, mask); @@ -584,13 +588,6 @@ 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, "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); @@ -612,6 +609,24 @@ 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->node, 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->node, PM_QOS_UPDATE_REQ, value); + } + } +#endif } EXPORT_SYMBOL_GPL(pm_qos_add_request);