On 2017/1/6 2:29, Lorenzo Pieralisi wrote:
Commit 618f535a6062 ("ACPI/IORT: Add single mapping function") introduced a function (iort_node_get_id()) to retrieve ids for IORT named components.iort_node_get_id() takes an index as input to refer to a specific mapping entry in the mapping array to retrieve the id at a specific index provided the index is below the total mapping count; currently the index is used to retrieve the mapping value from the correct entry but not to dereference the correct entry while retrieving the mapping output_reference (ie IORT parent pointer), which consequently always resolves to the output_reference of the first entry in the mapping array. Update the map array entry pointer computation in iort_node_get_id() to take into account the index value, fixing the issue. Fixes: 618f535a6062 ("ACPI/IORT: Add single mapping function") Reported-by: Hanjun Guo <hanjun....@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieral...@arm.com> Cc: Hanjun Guo <hanjun....@linaro.org> Cc: Sinan Kaya <ok...@codeaurora.org> Cc: Tomasz Nowicki <t...@semihalf.com> Cc: Nate Watterson <nwatt...@codeaurora.org> Cc: "Rafael J. Wysocki" <r...@rjwysocki.net> --- drivers/acpi/arm64/iort.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index e0d2e6e..ba156c5 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -333,7 +333,7 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node, return NULL; map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, - node->mapping_offset); + node->mapping_offset + index * sizeof(*map)); /* Firmware bug! */ if (!map->output_reference) { @@ -348,10 +348,10 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node, if (!(IORT_TYPE_MASK(parent->type) & type_mask)) return NULL; - if (map[index].flags & ACPI_IORT_ID_SINGLE_MAPPING) { + if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) { if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT || node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) { - *id_out = map[index].output_base; + *id_out = map->output_base; return parent; } }
Reviewed-by: Hanjun Guo <hanjun....@linaro.org>
