mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
4d395c5e74
When we walk up the device hierarchy in tb_acpi_add_link() make sure we
break the loop if the device has no parent. Otherwise we may crash the
kernel by dereferencing a NULL pointer.
Fixes: b2be2b05cf
("thunderbolt: Create device links from ACPI description")
Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
118 lines
2.9 KiB
C
118 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* ACPI support
|
|
*
|
|
* Copyright (C) 2020, Intel Corporation
|
|
* Author: Mika Westerberg <mika.westerberg@linux.intel.com>
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
|
|
#include "tb.h"
|
|
|
|
static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
|
|
void **return_value)
|
|
{
|
|
struct fwnode_reference_args args;
|
|
struct fwnode_handle *fwnode;
|
|
struct tb_nhi *nhi = data;
|
|
struct acpi_device *adev;
|
|
struct pci_dev *pdev;
|
|
struct device *dev;
|
|
int ret;
|
|
|
|
if (acpi_bus_get_device(handle, &adev))
|
|
return AE_OK;
|
|
|
|
fwnode = acpi_fwnode_handle(adev);
|
|
ret = fwnode_property_get_reference_args(fwnode, "usb4-host-interface",
|
|
NULL, 0, 0, &args);
|
|
if (ret)
|
|
return AE_OK;
|
|
|
|
/* It needs to reference this NHI */
|
|
if (nhi->pdev->dev.fwnode != args.fwnode)
|
|
goto out_put;
|
|
|
|
/*
|
|
* Try to find physical device walking upwards to the hierarcy.
|
|
* We need to do this because the xHCI driver might not yet be
|
|
* bound so the USB3 SuperSpeed ports are not yet created.
|
|
*/
|
|
dev = acpi_get_first_physical_node(adev);
|
|
while (!dev) {
|
|
adev = adev->parent;
|
|
if (!adev)
|
|
break;
|
|
dev = acpi_get_first_physical_node(adev);
|
|
}
|
|
|
|
if (!dev)
|
|
goto out_put;
|
|
|
|
/*
|
|
* Check that the device is PCIe. This is because USB3
|
|
* SuperSpeed ports have this property and they are not power
|
|
* managed with the xHCI and the SuperSpeed hub so we create the
|
|
* link from xHCI instead.
|
|
*/
|
|
while (dev && !dev_is_pci(dev))
|
|
dev = dev->parent;
|
|
|
|
if (!dev)
|
|
goto out_put;
|
|
|
|
/*
|
|
* Check that this actually matches the type of device we
|
|
* expect. It should either be xHCI or PCIe root/downstream
|
|
* port.
|
|
*/
|
|
pdev = to_pci_dev(dev);
|
|
if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI ||
|
|
(pci_is_pcie(pdev) &&
|
|
(pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ||
|
|
pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) {
|
|
const struct device_link *link;
|
|
|
|
link = device_link_add(&pdev->dev, &nhi->pdev->dev,
|
|
DL_FLAG_AUTOREMOVE_SUPPLIER |
|
|
DL_FLAG_PM_RUNTIME);
|
|
if (link) {
|
|
dev_dbg(&nhi->pdev->dev, "created link from %s\n",
|
|
dev_name(&pdev->dev));
|
|
} else {
|
|
dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
|
|
dev_name(&pdev->dev));
|
|
}
|
|
}
|
|
|
|
out_put:
|
|
fwnode_handle_put(args.fwnode);
|
|
return AE_OK;
|
|
}
|
|
|
|
/**
|
|
* tb_acpi_add_links() - Add device links based on ACPI description
|
|
* @nhi: Pointer to NHI
|
|
*
|
|
* Goes over ACPI namespace finding tunneled ports that reference to
|
|
* @nhi ACPI node. For each reference a device link is added. The link
|
|
* is automatically removed by the driver core.
|
|
*/
|
|
void tb_acpi_add_links(struct tb_nhi *nhi)
|
|
{
|
|
acpi_status status;
|
|
|
|
if (!has_acpi_companion(&nhi->pdev->dev))
|
|
return;
|
|
|
|
/*
|
|
* Find all devices that have usb4-host-controller interface
|
|
* property that references to this NHI.
|
|
*/
|
|
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 32,
|
|
tb_acpi_add_link, NULL, nhi, NULL);
|
|
if (ACPI_FAILURE(status))
|
|
dev_warn(&nhi->pdev->dev, "failed to enumerate tunneled ports\n");
|
|
}
|