diff mbox

[RESEND,v2,4/7] powerpc/pci: Don't scan empty slot

Message ID 1424157203-691-5-git-send-email-gwshan@linux.vnet.ibm.com (mailing list archive)
State Changes Requested
Delegated to: Benjamin Herrenschmidt
Headers show

Commit Message

Gavin Shan Feb. 17, 2015, 7:13 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 6e2b4e3..270a26d 100644
--- a/arch/powerpc/kernel/pci-hotplug.c
+++ b/arch/powerpc/kernel/pci-hotplug.c
@@ -120,7 +120,8 @@  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