On Fri, Dec 8, 2017 at 5:40 AM, Sinan Kaya <okaya@xxxxxxxxxxxxxx> wrote:
> 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);
Do you really need this duplication? You may as well call
ged_shutdown() from here.
And the local variable is redundant too.
I guess it would be better to just fold ged_cleanup_irq() into
ged_shutdown() and call that from ged_remove().
> 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),
> --
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