Re: [RFC Patch 12/19] ACPI: Enforce stricter checks for address space descriptors

From: Rafael J. Wysocki
Date: Tue Jan 20 2015 - 19:23:19 EST


On Thursday, January 08, 2015 10:32:59 AM Jiang Liu wrote:
> Enforce stricter checks for address space descriptors according to
> ACPI spec.

So is the spec the only reason for doing this? If so, I'd say don't.

> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
> ---
> drivers/acpi/resource.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index 26b47f1da523..e82149e44347 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -192,6 +192,14 @@ static bool acpi_decode_space(struct resource *res,
> bool wp = base->info.mem.write_protect;
> u64 len = addr->address_length;
>
> + /*
> + * Filter out invalid descriptor according to ACPI Spec 5.0, section
> + * 6.4.3.5 Address Space Resource Descriptors.
> + */
> + if ((base->min_address_fixed != base->max_address_fixed && len) ||
> + (base->min_address_fixed && base->max_address_fixed && !len))
> + return false;
> +
> res->start = addr->minimum;
> res->end = addr->maximum;
>
>

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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