[PATCH 2/2] MIPS/PCI: Fix pcibios_scan_bus() NULL check code path

From: Lorenzo Pieralisi
Date: Mon Jul 10 2017 - 08:32:40 EST


If pci_scan_root_bus() fails (ie returns NULL) pcibios_scan_bus() must
return immediately since the struct pci_bus pointer it returns is not
valid and cannot be used.

Move code checking the pci_scan_root_bus() return value to reinstate
proper pcibios_scanbus() error path behaviour.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Paul Burton <paul.burton@xxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
arch/mips/pci/pci-legacy.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/mips/pci/pci-legacy.c b/arch/mips/pci/pci-legacy.c
index 174575a..71d62f8 100644
--- a/arch/mips/pci/pci-legacy.c
+++ b/arch/mips/pci/pci-legacy.c
@@ -89,16 +89,16 @@ static void pcibios_scanbus(struct pci_controller *hose)
pci_add_resource(&resources, hose->busn_resource);
bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
&resources);
- hose->bus = bus;
-
- need_domain_info = need_domain_info || pci_domain_nr(bus);
- set_pci_need_domain_info(hose, need_domain_info);
-
if (!bus) {
pci_free_resource_list(&resources);
return;
}

+ hose->bus = bus;
+
+ need_domain_info = need_domain_info || pci_domain_nr(bus);
+ set_pci_need_domain_info(hose, need_domain_info);
+
next_busno = bus->busn_res.end + 1;
/* Don't allow 8-bit bus number overflow inside the hose -
reserve some space for bridges. */
--
2.10.0