From cb4cb4ac7338c28b047760be187355ed9c783e72 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Thu, 5 Mar 2009 19:28:40 -0700 Subject: [PATCH] PCIe: AER: during disable, check subordinate before walking Commit 47a8b0cc (Enable PCIe AER only after checking firmware support) wants to walk the PCI bus in the remove path to disable AER, and calls pci_walk_bus for downstream bridges. Unfortunately, in the remove path, we remove devices and bridges in a depth-first manner, starting with the furthest downstream bridge and working our way backwards. The furthest downstream bridges will not have a dev->subordinate, and we hit a NULL deref in pci_walk_bus. Check for dev->subordinate first before attempting to walk the PCI hierarchy below us. Acked-by: Andrew Patterson Signed-off-by: Alex Chiang Signed-off-by: Matthew Wilcox --- drivers/pci/pcie/aer/aerdrv_core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c index d0c9736..3825750 100644 --- a/drivers/pci/pcie/aer/aerdrv_core.c +++ b/drivers/pci/pcie/aer/aerdrv_core.c @@ -133,6 +133,9 @@ static void set_downstream_devices_error_reporting(struct pci_dev *dev, bool enable) { set_device_error_reporting(dev, &enable); + + if (!dev->subordinate) + return; pci_walk_bus(dev->subordinate, set_device_error_reporting, &enable); } -- 1.8.2.3