On Thursday 25 March 2010, Bjorn Helgaas wrote: > > 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: Bjorn Helgaas <bjorn.helgaas@xxxxxx> Acked-by: Rafael J. Wysocki <rjw@xxxxxxx> > --- > > drivers/pnp/pnpacpi/rsparser.c | 42 +++++++++++++++++++++++++++++----------- > 1 files changed, 30 insertions(+), 12 deletions(-) > > > diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c > index 54514aa..fe5bfa9 100644 > --- a/drivers/pnp/pnpacpi/rsparser.c > +++ b/drivers/pnp/pnpacpi/rsparser.c > @@ -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, > > > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
