On Thu, Jan 10, 2019 at 01:35:51PM +0000, Jean-Philippe Brucker wrote:
> When executed for a PCI_ROOT_COMPLEX type, iort_match_node_callback()
> expects the opaque pointer argument to be a PCI bus device. At the
> moment rc_dma_get_range() passes the PCI endpoint instead of the bus,
> and we've been lucky to have pci_domain_nr(ptr) return 0 instead of
> crashing. Pass the bus device to iort_scan_node().
Arguably it would have been better if it crashed instead of returning 0
(which is the default PCI domain number in most systems) by sheer luck.
Anyway - thanks for spotting this, I will mark if for stable and send it
to Will for an upcoming -rc asap.
Thanks,
Lorenzo
> Reported-by: Eric Auger <eric.auger@xxxxxxxxxx>
> Fixes: 5ac65e8c8941 ("ACPI/IORT: Support address size limit for root complexes")
> Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
> ---
> drivers/acpi/arm64/iort.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index fdd90ffceb85..c08afe44c488 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -952,9 +952,10 @@ static int rc_dma_get_range(struct device *dev, u64 *size)
> {
> struct acpi_iort_node *node;
> struct acpi_iort_root_complex *rc;
> + struct pci_bus *pbus = to_pci_dev(dev)->bus;
>
> node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
> - iort_match_node_callback, dev);
> + iort_match_node_callback, &pbus->dev);
> if (!node || node->revision < 1)
> return -ENODEV;
>
> --
> 2.19.1
>
