[PATCH v2 2/4] ACPI/APMT: Don't register invalid resource

[Lorenzo Pieralisi]

On Mon, Jun 05, 2023 at 06:01:32PM +0100, Robin Murphy wrote:
> Don't register a resource for the second page unless the dual-page
> extension flag is actually present to say it's valid.
> 
> CC: Lorenzo Pieralisi <lpieralisi at kernel.org>
> CC: Sudeep Holla <sudeep.holla at arm.com>
> Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> Reviewed-by: Hanjun Guo <guohanjun at huawei.com>
> Reviewed-and-tested-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> ---
>  drivers/acpi/arm64/apmt.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)

Acked-by: Lorenzo Pieralisi <lpieralisi at kernel.org>

As you mentioned in v1 I don't think we need to backport this
since the kernel is working around it (in code you are cleaning
up) even though that would not hurt.

Lorenzo

> diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c
> index 8cab69fa5d59..aa7d5c3c0dd8 100644
> --- a/drivers/acpi/arm64/apmt.c
> +++ b/drivers/acpi/arm64/apmt.c
> @@ -35,11 +35,13 @@ static int __init apmt_init_resources(struct resource *res,
>  
>  	num_res++;
>  
> -	res[num_res].start = node->base_address1;
> -	res[num_res].end = node->base_address1 + SZ_4K - 1;
> -	res[num_res].flags = IORESOURCE_MEM;
> +	if (node->flags & ACPI_APMT_FLAGS_DUAL_PAGE) {
> +		res[num_res].start = node->base_address1;
> +		res[num_res].end = node->base_address1 + SZ_4K - 1;
> +		res[num_res].flags = IORESOURCE_MEM;
>  
> -	num_res++;
> +		num_res++;
> +	}
>  
>  	if (node->ovflw_irq != 0) {
>  		trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE);
> -- 
> 2.39.2.101.g768bb238c484.dirty
>