From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- include/kunit/device.h | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 include/kunit/device.h (limited to 'include/kunit/device.h') diff --git a/include/kunit/device.h b/include/kunit/device.h new file mode 100644 index 000000000..2450110ad --- /dev/null +++ b/include/kunit/device.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KUnit basic device implementation + * + * Helpers for creating and managing fake devices for KUnit tests. + * + * Copyright (C) 2023, Google LLC. + * Author: David Gow + */ + +#ifndef _KUNIT_DEVICE_H +#define _KUNIT_DEVICE_H + +#if IS_ENABLED(CONFIG_KUNIT) + +#include + +struct device; +struct device_driver; + +/** + * kunit_driver_create() - Create a struct device_driver attached to the kunit_bus + * @test: The test context object. + * @name: The name to give the created driver. + * + * Creates a struct device_driver attached to the kunit_bus, with the name @name. + * This driver will automatically be cleaned up on test exit. + * + * Return: a stub struct device_driver, managed by KUnit, with the name @name. + */ +struct device_driver *kunit_driver_create(struct kunit *test, const char *name); + +/** + * kunit_device_register() - Create a struct device for use in KUnit tests + * @test: The test context object. + * @name: The name to give the created device. + * + * Creates a struct kunit_device (which is a struct device) with the given name, + * and a corresponding driver. The device and driver will be cleaned up on test + * exit, or when kunit_device_unregister is called. See also + * kunit_device_register_with_driver, if you wish to provide your own + * struct device_driver. + * + * Return: a pointer to a struct device which will be cleaned up when the test + * exits, or an error pointer if the device could not be allocated or registered. + */ +struct device *kunit_device_register(struct kunit *test, const char *name); + +/** + * kunit_device_register_with_driver() - Create a struct device for use in KUnit tests + * @test: The test context object. + * @name: The name to give the created device. + * @drv: The struct device_driver to associate with the device. + * + * Creates a struct kunit_device (which is a struct device) with the given + * name, and driver. The device will be cleaned up on test exit, or when + * kunit_device_unregister is called. See also kunit_device_register, if you + * wish KUnit to create and manage a driver for you. + * + * Return: a pointer to a struct device which will be cleaned up when the test + * exits, or an error pointer if the device could not be allocated or registered. + */ +struct device *kunit_device_register_with_driver(struct kunit *test, + const char *name, + const struct device_driver *drv); + +/** + * kunit_device_unregister() - Unregister a KUnit-managed device + * @test: The test context object which created the device + * @dev: The device. + * + * Unregisters and destroys a struct device which was created with + * kunit_device_register or kunit_device_register_with_driver. If KUnit created + * a driver, cleans it up as well. + */ +void kunit_device_unregister(struct kunit *test, struct device *dev); + +#endif + +#endif -- cgit v1.3.1