On 10/01/2019 14:53, Jean-Philippe Brucker wrote:
On 10/01/2019 14:17, Robin Murphy wrote:
On 10/01/2019 13:35, 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().
Oops - that makes sense, and I can now see the combination of
circumstances that would have led me to overlook it at the time. Sorry
about that! However..
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;
...is this still right if the device is beyond a switch or other bridge
and not on the root bus?
My understanding is that the pci_dev still has a valid ->bus
representing its nearest upstream bridge, and the domain_nr attribute of
each bus is copied from its parent by pci_alloc_bus(). Other places in
the kernel seem to do the same thing, including iort_iommu_configure()
in this file
OK, having re-read the commit message properly and gone and looked at
the rest of the code, I think my concern is indeed unfounded - thanks.
Mostly I'd forgotten that the IORT node is associated with the segment
number rather than the actual RC device, so with doubts relieved:
Acked-by: Robin Murphy <robin.murphy@xxxxxxx>
Cheers,
Robin.
