diff mbox

[v4,11/21] powerpc/pci: Don't scan empty slot

Message ID 1430460188-31343-12-git-send-email-gwshan@linux.vnet.ibm.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Gavin Shan May 1, 2015, 6:02 a.m. UTC
In hotplug case, function pcibios_add_pci_devices() is called to
rescan the specified PCI bus, which might not have any child devices.
Access to the PCI bus's child device node will cause kernel crash
without exception. The patch adds condition of skipping scanning
PCI bus without child devices, in order to avoid kernel crash.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/pci-hotplug.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c
index 0040343..651a866a 100644
--- a/arch/powerpc/kernel/pci-hotplug.c
+++ b/arch/powerpc/kernel/pci-hotplug.c
@@ -92,7 +92,8 @@  void pcibios_add_pci_devices(struct pci_bus * bus)
 	if (mode == PCI_PROBE_DEVTREE) {
 		/* use ofdt-based probe */
 		of_rescan_bus(dn, bus);
-	} else if (mode == PCI_PROBE_NORMAL) {
+	} else if (mode == PCI_PROBE_NORMAL &&
+		   dn->child && PCI_DN(dn->child)) {
 		/*
 		 * Use legacy probe. In the partial hotplug case, we
 		 * probably have grandchildren devices unplugged. So