[PATCH] pci: of : fix kernel crash

[Murali Karicheri]

This is a debug patch to root cause the kernel crash

	commit 0b2af171520e5d5e7d5b5f479b90a6a5014d9df6

	PCI: Update DMA configuration from DT

Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx>
---
 drivers/of/of_pci.c       |    8 ++++++++
 drivers/pci/host-bridge.c |    5 +++++
 2 files changed, 13 insertions(+)

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 86d3c38..5a59fb8 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -129,6 +129,14 @@ void of_pci_dma_configure(struct pci_dev *pci_dev)
 	struct device *dev = &pci_dev->dev;
 	struct device *bridge = pci_get_host_bridge_device(pci_dev);
 
+	if (!bridge || !bridge->parent) {
+		if (!bridge)
+			pr_err("PCI bridge not found\n");
+		if (!bridge->parent)
+			pr_err("PCI bridge parent not found\n");
+		return;
+	}
+
 	of_dma_configure(dev, bridge->parent->of_node);
 	pci_put_host_bridge_device(bridge);
 }
diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index 3e5bbf9..ef2ab51 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -28,6 +28,11 @@ struct device *pci_get_host_bridge_device(struct pci_dev *dev)
 	struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
 	struct device *bridge = root_bus->bridge;
 
+	if (!bridge) {
+		pr_err("PCI: bridge not found\n");
+		return NULL;
+	}
+
 	kobject_get(&bridge->kobj);
 	return bridge;
 }
-- 
1.7.9.5


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