4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zachary Zhang <zhangzg@xxxxxxxxxxx> commit 91a2968e245d6ba616db37001fa1a043078b1a65 upstream. The PCIE I/O and MEM resource allocation mechanism is that root bus goes through the following steps: 1. Check PCI bridges' range and computes I/O and Mem base/limits. 2. Sort all subordinate devices I/O and MEM resource requirements and allocate the resources and writes/updates subordinate devices' requirements to PCI bridges I/O and Mem MEM/limits registers. Currently, PCI Aardvark driver only handles the second step and lacks the first step, so there is an I/O and MEM resource allocation failure when using a PCI switch. This commit fixes that by sizing bridges before doing the resource allocation. Fixes: 8c39d710363c1 ("PCI: aardvark: Add Aardvark PCI host controller driver") Signed-off-by: Zachary Zhang <zhangzg@xxxxxxxxxxx> [Thomas: edit commit log.] Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxx> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/controller/pci-aardvark.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -952,6 +952,7 @@ static int advk_pcie_probe(struct platfo bus = bridge->bus; + pci_bus_size_bridges(bus); pci_bus_assign_resources(bus); list_for_each_entry(child, &bus->children, node)