[PATCH V3] ACPI / GED: unregister interrupts during shutdown

From: Sinan Kaya
Date: Thu Dec 07 2017 - 23:41:05 EST


Some GED interrupts could be pending by the time we are doing a reboot.

Even though GED driver uses devm_request_irq() to register the interrupt
handler, the handler is not being freed on time during a shutdown since
the driver is missing a shutdown callback.

If the ACPI handler is no longer available, this causes an interrupt
storm and delays shutdown.

1. Don't use devm family of functions for IRQ registration/free
2. Keep track of the events since free_irq() requires the dev_id parameter
passed into the request_irq() function.
3. Call free_irq() on both remove and shutdown explicitly.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/acpi/evged.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 49 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/evged.c b/drivers/acpi/evged.c
index 46f0603..38cb00e 100644
--- a/drivers/acpi/evged.c
+++ b/drivers/acpi/evged.c
@@ -49,6 +49,11 @@

#define MODULE_NAME "acpi-ged"

+struct acpi_ged_device {
+ struct device *dev;
+ struct list_head event_list;
+};
+
struct acpi_ged_event {
struct list_head node;
struct device *dev;
@@ -76,7 +81,8 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
unsigned int irq;
unsigned int gsi;
unsigned int irqflags = IRQF_ONESHOT;
- struct device *dev = context;
+ struct acpi_ged_device *geddev = context;
+ struct device *dev = geddev->dev;
acpi_handle handle = ACPI_HANDLE(dev);
acpi_handle evt_handle;
struct resource r;
@@ -102,8 +108,6 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
return AE_ERROR;
}

- dev_info(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
-
event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL);
if (!event)
return AE_ERROR;
@@ -116,26 +120,63 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
if (r.flags & IORESOURCE_IRQ_SHAREABLE)
irqflags |= IRQF_SHARED;

- if (devm_request_threaded_irq(dev, irq, NULL, acpi_ged_irq_handler,
- irqflags, "ACPI:Ged", event)) {
+ if (request_threaded_irq(irq, NULL, acpi_ged_irq_handler,
+ irqflags, "ACPI:Ged", event)) {
dev_err(dev, "failed to setup event handler for irq %u\n", irq);
return AE_ERROR;
}

+ dev_dbg(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
+ list_add_tail(&event->node, &geddev->event_list);
return AE_OK;
}

static int ged_probe(struct platform_device *pdev)
{
+ struct acpi_ged_device *geddev;
acpi_status acpi_ret;

+ geddev = devm_kzalloc(&pdev->dev, sizeof(*geddev), GFP_KERNEL);
+ if (!geddev)
+ return -ENOMEM;
+
+ geddev->dev = &pdev->dev;
+ INIT_LIST_HEAD(&geddev->event_list);
acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS",
- acpi_ged_request_interrupt, &pdev->dev);
+ acpi_ged_request_interrupt, geddev);
if (ACPI_FAILURE(acpi_ret)) {
dev_err(&pdev->dev, "unable to parse the _CRS record\n");
return -EINVAL;
}
+ platform_set_drvdata(pdev, geddev);
+
+ return 0;
+}
+
+static void ged_cleanup_irq(struct acpi_ged_device *geddev)
+{
+ struct acpi_ged_event *event, *next;
+
+ list_for_each_entry_safe(event, next, &geddev->event_list, node) {
+ free_irq(event->irq, event);
+ list_del(&event->node);
+ dev_dbg(geddev->dev, "GED releasing GSI %u @ IRQ %u\n",
+ event->gsi, event->irq);
+ }
+}
+
+static void ged_shutdown(struct platform_device *pdev)
+{
+ struct acpi_ged_device *geddev = platform_get_drvdata(pdev);
+
+ ged_cleanup_irq(geddev);
+}
+
+static int ged_remove(struct platform_device *pdev)
+{
+ struct acpi_ged_device *geddev = platform_get_drvdata(pdev);

+ ged_cleanup_irq(geddev);
return 0;
}

@@ -146,6 +187,8 @@ static int ged_probe(struct platform_device *pdev)

static struct platform_driver ged_driver = {
.probe = ged_probe,
+ .remove = ged_remove,
+ .shutdown = ged_shutdown,
.driver = {
.name = MODULE_NAME,
.acpi_match_table = ACPI_PTR(ged_acpi_ids),
--
1.9.1