From: David Daney <david.daney@cavium.com>
Date: Tue, 16 Aug 2011 18:24:37 +0000 (-0700)
Subject: PCI: OF: Don't crash when bridge parent is NULL.
X-Git-Tag: Ubuntu-5.0.0-8.9~17840^2
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=69566dd8be42dea7a22f625abc96e65bb4b45d1f;p=mirror_ubuntu-disco-kernel.git

PCI: OF: Don't crash when bridge parent is NULL.

In pcibios_get_phb_of_node(), we will crash while booting if
bus->bridge->parent is NULL.

Check for this case and avoid dereferencing the NULL pointer.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index c94d37ec55c8..f0929934bb7a 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -55,7 +55,7 @@ struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
 	 */
 	if (bus->bridge->of_node)
 		return of_node_get(bus->bridge->of_node);
-	if (bus->bridge->parent->of_node)
+	if (bus->bridge->parent && bus->bridge->parent->of_node)
 		return of_node_get(bus->bridge->parent->of_node);
 	return NULL;
 }