PCI: iproc: Save host bridge window resource in struct iproc_pcie

The host bridge memory window resource is inserted into the iomem_resource
tree and cannot be deallocated until the host bridge itself is removed.

Previously, the window was on the stack, which meant the iomem_resource
entry pointed into the stack and was corrupted as soon as the probe
function returned, which caused memory corruption and errors like this:

  pcie_iproc_bcma bcma0:8: resource collision: [mem 0x40000000-0x47ffffff] conflicts with PCIe MEM space [mem 0x40000000-0x47ffffff]

Move the memory window resource from the stack into struct iproc_pcie so
its lifetime matches that of the host bridge.

Fixes: c3245a5664 ("PCI: iproc: Request host bridge window resources")
Reported-and-tested-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v4.8+

drivers/pci/host/pcie-iproc-bcma.c

@@ -44,8 +44,7 @@ static int iproc_pcie_bcma_probe(struct bcma_device *bdev)
 {
 	struct device *dev = &bdev->dev;
 	struct iproc_pcie *pcie;
-	LIST_HEAD(res);
-	struct resource res_mem;
+	LIST_HEAD(resources);
 	int ret;
 
 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
@@ -63,22 +62,23 @@ static int iproc_pcie_bcma_probe(struct bcma_device *bdev)
 
 	pcie->base_addr = bdev->addr;
 
-	res_mem.start = bdev->addr_s[0];
-	res_mem.end = bdev->addr_s[0] + SZ_128M - 1;
-	res_mem.name = "PCIe MEM space";
-	res_mem.flags = IORESOURCE_MEM;
-	pci_add_resource(&res, &res_mem);
+	pcie->mem.start = bdev->addr_s[0];
+	pcie->mem.end = bdev->addr_s[0] + SZ_128M - 1;
+	pcie->mem.name = "PCIe MEM space";
+	pcie->mem.flags = IORESOURCE_MEM;
+	pci_add_resource(&resources, &pcie->mem);
 
 	pcie->map_irq = iproc_pcie_bcma_map_irq;
 
-	ret = iproc_pcie_setup(pcie, &res);
-	if (ret)
+	ret = iproc_pcie_setup(pcie, &resources);
+	if (ret) {
 		dev_err(dev, "PCIe controller setup failed\n");
-
-	pci_free_resource_list(&res);
+		pci_free_resource_list(&resources);
+		return ret;
+	}
 
 	bcma_set_drvdata(bdev, pcie);
-	return ret;
+	return 0;
 }
 
 static void iproc_pcie_bcma_remove(struct bcma_device *bdev)

drivers/pci/host/pcie-iproc-platform.c

@@ -51,7 +51,7 @@ static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 	struct device_node *np = dev->of_node;
 	struct resource reg;
 	resource_size_t iobase = 0;
-	LIST_HEAD(res);
+	LIST_HEAD(resources);
 	int ret;
 
 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
@@ -96,10 +96,10 @@ static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 		pcie->phy = NULL;
 	}
 
-	ret = of_pci_get_host_bridge_resources(np, 0, 0xff, &res, &iobase);
+	ret = of_pci_get_host_bridge_resources(np, 0, 0xff, &resources,
+					       &iobase);
 	if (ret) {
-		dev_err(dev,
-			"unable to get PCI host bridge resources\n");
+		dev_err(dev, "unable to get PCI host bridge resources\n");
 		return ret;
 	}
 
@@ -112,14 +112,15 @@ static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 		pcie->map_irq = of_irq_parse_and_map_pci;
 	}
 
-	ret = iproc_pcie_setup(pcie, &res);
-	if (ret)
+	ret = iproc_pcie_setup(pcie, &resources);
+	if (ret) {
 		dev_err(dev, "PCIe controller setup failed\n");
-
-	pci_free_resource_list(&res);
+		pci_free_resource_list(&resources);
+		return ret;
+	}
 
 	platform_set_drvdata(pdev, pcie);
-	return ret;
+	return 0;
 }
 
 static int iproc_pcie_pltfm_remove(struct platform_device *pdev)

drivers/pci/host/pcie-iproc.h

@@ -90,6 +90,7 @@ struct iproc_pcie {
 #ifdef CONFIG_ARM
 	struct pci_sys_data sysdata;
 #endif
+	struct resource mem;
 	struct pci_bus *root_bus;
 	struct phy *phy;
 	int (*map_irq)(const struct pci_dev *, u8, u8);