Re: [PATCH v1 4/4] ACPI: scan: Make acpi_processor_add() check the device enabled bit

From: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Linux ACPI <linux-acpi@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	"Russell King (Oracle)" <linux@armlinux.org.uk>
Subject: Re: [PATCH v1 4/4] ACPI: scan: Make acpi_processor_add() check the device enabled bit
Date: Thu, 22 Feb 2024 18:47:38 +0000	[thread overview]
Message-ID: <20240222184738.00000bf7@Huawei.com> (raw)
In-Reply-To: <3298279.44csPzL39Z@kreacher>

On Wed, 21 Feb 2024 21:03:17 +0100
"Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:

> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Modify acpi_processor_add() return an error if _STA returns the enabled
> bit clear for the given processor device, so as to avoid using processors
> that don't decode their resources, as per the ACPI specification. [1]
> 
> Link: https://uefi.org/specs/ACPI/6.5/06_Device_Configuration.html#sta-device-status # [1]
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

This does the job for us so if you are happier with this approach
that works for me.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/acpi/acpi_processor.c |    3 +++
>  1 file changed, 3 insertions(+)
> 
> Index: linux-pm/drivers/acpi/acpi_processor.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/acpi_processor.c
> +++ linux-pm/drivers/acpi/acpi_processor.c
> @@ -381,6 +381,9 @@ static int acpi_processor_add(struct acp
>  	struct device *dev;
>  	int result = 0;
>  
> +	if (!acpi_device_is_enabled(device))
> +		return -ENODEV;
> +
>  	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
>  	if (!pr)
>  		return -ENOMEM;
> 
> 
> 