From 1a4b1a41b8a3d5256019854e851beed063b34344 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt <benh@kernel.crashing.org> Date: Tue, 13 Sep 2011 15:16:33 -0300 Subject: 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> --- drivers/pci/probe.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index b1187ff31d89..f3f94a5c068f 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1351,7 +1351,8 @@ static int pcie_find_smpss(struct pci_dev *dev, void *data) * will occur as normal. */ if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) || - dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)) + (dev->bus->self && + dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))) *smpss = 0; if (*smpss > dev->pcie_mpss) -- cgit v1.2.2