Commit 3162b6f0 authored by Bjorn Helgaas's avatar Bjorn Helgaas Committed by Len Brown
Browse files

PNPACPI: truncate _CRS windows with _LEN > _MAX - _MIN + 1 

The ACPI spec (sec 6.4.3.5 in v4.0) requires that for Address Space Resource
Descriptors, _LEN <= _MAX - _MIN + 1 in all cases, but there are BIOSes that
violate this.  We experimentally determined that Windows truncates the
resource so it doesn't extend past _MAX, so let's do the same thing in
Linux.

http://bugzilla.kernel.org/show_bug.cgi?id=15480



Signed-off-by: default avatarBjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 2eaa9cfd

drivers/pnp/pnpacpi/rsparser.c

+30 −12
Original line number Diff line number Diff line
@@ -273,12 +273,33 @@ static void pnpacpi_parse_allocated_busresource(struct pnp_dev *dev, 
	pnp_add_bus_resource(dev, start, end);

}



static u64 addr_space_length(struct pnp_dev *dev, u64 min, u64 max, u64 len)

{

	u64 max_len;



	max_len = max - min + 1;

	if (len <= max_len)

		return len;



	/*

	 * Per 6.4.3.5, _LEN cannot exceed _MAX - _MIN + 1, but some BIOSes

	 * don't do this correctly, e.g.,

	 * https://bugzilla.kernel.org/show_bug.cgi?id=15480

	 */

	dev_info(&dev->dev,

	         "resource length %#llx doesn't fit in %#llx-%#llx, trimming\n",

		 (unsigned long long) len, (unsigned long long) min,

		 (unsigned long long) max);

	return max_len;

}



static void pnpacpi_parse_allocated_address_space(struct pnp_dev *dev,

						  struct acpi_resource *res)

{

	struct acpi_resource_address64 addr, *p = &addr;

	acpi_status status;

	int window;

	u64 len;



	status = acpi_resource_to_address64(res, p);

	if (!ACPI_SUCCESS(status)) {
@@ -287,20 +308,18 @@ static void pnpacpi_parse_allocated_address_space(struct pnp_dev *dev, 
		return;

	}



	len = addr_space_length(dev, p->minimum, p->maximum, p->address_length);

	window = (p->producer_consumer == ACPI_PRODUCER) ? 1 : 0;



	if (p->resource_type == ACPI_MEMORY_RANGE)

		pnpacpi_parse_allocated_memresource(dev,

			p->minimum, p->address_length,

		pnpacpi_parse_allocated_memresource(dev, p->minimum, len,

			p->info.mem.write_protect, window);

	else if (p->resource_type == ACPI_IO_RANGE)

		pnpacpi_parse_allocated_ioresource(dev,

			p->minimum, p->address_length,

		pnpacpi_parse_allocated_ioresource(dev, p->minimum, len,

			p->granularity == 0xfff ? ACPI_DECODE_10 :

				ACPI_DECODE_16, window);

	else if (p->resource_type == ACPI_BUS_NUMBER_RANGE)

		pnpacpi_parse_allocated_busresource(dev, p->minimum,

						    p->address_length);

		pnpacpi_parse_allocated_busresource(dev, p->minimum, len);

}



static void pnpacpi_parse_allocated_ext_address_space(struct pnp_dev *dev,
@@ -308,21 +327,20 @@ static void pnpacpi_parse_allocated_ext_address_space(struct pnp_dev *dev, 
{

	struct acpi_resource_extended_address64 *p = &res->data.ext_address64;

	int window;

	u64 len;



	len = addr_space_length(dev, p->minimum, p->maximum, p->address_length);

	window = (p->producer_consumer == ACPI_PRODUCER) ? 1 : 0;



	if (p->resource_type == ACPI_MEMORY_RANGE)

		pnpacpi_parse_allocated_memresource(dev,

			p->minimum, p->address_length,

		pnpacpi_parse_allocated_memresource(dev, p->minimum, len,

			p->info.mem.write_protect, window);

	else if (p->resource_type == ACPI_IO_RANGE)

		pnpacpi_parse_allocated_ioresource(dev,

			p->minimum, p->address_length,

		pnpacpi_parse_allocated_ioresource(dev, p->minimum, len,

			p->granularity == 0xfff ? ACPI_DECODE_10 :

				ACPI_DECODE_16, window);

	else if (p->resource_type == ACPI_BUS_NUMBER_RANGE)

		pnpacpi_parse_allocated_busresource(dev, p->minimum,

						    p->address_length);

		pnpacpi_parse_allocated_busresource(dev, p->minimum, len);

}



static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,

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