Re: [PATCH] acpi: don't register acpi_pad driver if running as xen dom0

From: Rafael J. Wysocki
Date: Thu Oct 13 2016 - 18:00:33 EST


On Wednesday, October 12, 2016 01:11:45 PM Juergen Gross wrote:
> When running as Xen dom0 a special processor_aggregator driver is
> needed. Don't register the standard driver in this case.
>
> Without that check an error message:
>
> "Error: Driver 'processor_aggregator' is already registered,
> aborting..."
>
> will be displayed.
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---
> drivers/acpi/acpi_pad.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c
> index 8ea8211..1c3be12 100644
> --- a/drivers/acpi/acpi_pad.c
> +++ b/drivers/acpi/acpi_pad.c
> @@ -26,6 +26,7 @@
> #include <linux/slab.h>
> #include <linux/acpi.h>
> #include <asm/mwait.h>
> +#include <xen/xen.h>
>
> #define ACPI_PROCESSOR_AGGREGATOR_CLASS "acpi_pad"
> #define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
> @@ -477,6 +478,10 @@ static struct acpi_driver acpi_pad_driver = {
>
> static int __init acpi_pad_init(void)
> {
> + /* Xen acpi pad is responsible when running as Xen Dom0. */
> + if (xen_initial_domain())
> + return -ENODEV;
> +
> power_saving_mwait_init();
> if (power_saving_mwait_eax == 0)
> return -EINVAL;
>

Applied.

Thanks,
Rafael