tree fa62183e093cf032c74cac8149fb69a49b07b7e0
parent 2f4d3218e95d48de2951dcf2bea619ea49ef93de
author Benjamin Herrenschmidt <benh@kernel.crashing.org> 1315937793 -0300
committer Linus Torvalds <torvalds@linux-foundation.org> 1315955311 -0700

pci: Don't crash when reading mpss from root complex

In pcie_find_smpss(), we have the following statement:

 	if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
	    dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))

The problem is that at least on my machine, this gets called for the
root complex (virtual P2P bridge), and dev->bus->self is NULL since
the parent bus for this is not itself anchor to a PCI device.

This adds the necessary NULL check.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jon Mason <mason@myri.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>