mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 00:40:03 +00:00
![David Daney](/assets/img/avatar_default.png)
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>
61 lines
1.5 KiB
C
61 lines
1.5 KiB
C
/*
|
|
* PCI <-> OF mapping helpers
|
|
*
|
|
* Copyright 2011 IBM Corp.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_pci.h>
|
|
#include "pci.h"
|
|
|
|
void pci_set_of_node(struct pci_dev *dev)
|
|
{
|
|
if (!dev->bus->dev.of_node)
|
|
return;
|
|
dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
|
|
dev->devfn);
|
|
}
|
|
|
|
void pci_release_of_node(struct pci_dev *dev)
|
|
{
|
|
of_node_put(dev->dev.of_node);
|
|
dev->dev.of_node = NULL;
|
|
}
|
|
|
|
void pci_set_bus_of_node(struct pci_bus *bus)
|
|
{
|
|
if (bus->self == NULL)
|
|
bus->dev.of_node = pcibios_get_phb_of_node(bus);
|
|
else
|
|
bus->dev.of_node = of_node_get(bus->self->dev.of_node);
|
|
}
|
|
|
|
void pci_release_bus_of_node(struct pci_bus *bus)
|
|
{
|
|
of_node_put(bus->dev.of_node);
|
|
bus->dev.of_node = NULL;
|
|
}
|
|
|
|
struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
|
|
{
|
|
/* This should only be called for PHBs */
|
|
if (WARN_ON(bus->self || bus->parent))
|
|
return NULL;
|
|
|
|
/* Look for a node pointer in either the intermediary device we
|
|
* create above the root bus or it's own parent. Normally only
|
|
* the later is populated.
|
|
*/
|
|
if (bus->bridge->of_node)
|
|
return of_node_get(bus->bridge->of_node);
|
|
if (bus->bridge->parent && bus->bridge->parent->of_node)
|
|
return of_node_get(bus->bridge->parent->of_node);
|
|
return NULL;
|
|
}
|