The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From eac56aa3bc8af3d9b9850345d0f2da9d83529134 Mon Sep 17 00:00:00 2001
From: Johan Hovold johan@kernel.org Date: Fri, 17 Nov 2017 14:38:31 +0100 Subject: [PATCH] PCI: keystone: Fix interrupt-controller-node lookup
Fix child-node lookup during initialisation which was using the wrong OF-helper and ended up searching the whole device tree depth-first starting at the parent rather than just matching on its children.
To make things worse, the parent pci node could end up being prematurely freed as of_find_node_by_name() drops a reference to its first argument. Any matching child interrupt-controller node was also leaked.
Fixes: 0c4ffcfe1fbc ("PCI: keystone: Add TI Keystone PCIe driver") Cc: stable stable@vger.kernel.org # 3.18 Acked-by: Murali Karicheri m-karicheri2@ti.com Signed-off-by: Johan Hovold johan@kernel.org [lorenzo.pieralisi@arm.com: updated commit subject] Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com
diff --git a/drivers/pci/dwc/pci-keystone.c b/drivers/pci/dwc/pci-keystone.c index 5bee3af47588..39405598b22d 100644 --- a/drivers/pci/dwc/pci-keystone.c +++ b/drivers/pci/dwc/pci-keystone.c @@ -178,7 +178,7 @@ static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie, }
/* interrupt controller is in a child node */ - *np_temp = of_find_node_by_name(np_pcie, controller); + *np_temp = of_get_child_by_name(np_pcie, controller); if (!(*np_temp)) { dev_err(dev, "Node for %s is absent\n", controller); return -EINVAL; @@ -187,6 +187,7 @@ static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie, temp = of_irq_count(*np_temp); if (!temp) { dev_err(dev, "No IRQ entries in %s\n", controller); + of_node_put(*np_temp); return -EINVAL; }
@@ -204,6 +205,8 @@ static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie, break; }
+ of_node_put(*np_temp); + if (temp) { *num_irqs = temp; return 0;