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 --- drivers/acpi/tiny-power-button.c | 87 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 drivers/acpi/tiny-power-button.c (limited to 'drivers/acpi/tiny-power-button.c') diff --git a/drivers/acpi/tiny-power-button.c b/drivers/acpi/tiny-power-button.c new file mode 100644 index 000000000..92516ef84 --- /dev/null +++ b/drivers/acpi/tiny-power-button.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Josh Triplett"); +MODULE_DESCRIPTION("ACPI Tiny Power Button Driver"); +MODULE_LICENSE("GPL"); + +static int power_signal __read_mostly = CONFIG_ACPI_TINY_POWER_BUTTON_SIGNAL; +module_param(power_signal, int, 0644); +MODULE_PARM_DESC(power_signal, "Power button sends this signal to init"); + +static const struct acpi_device_id tiny_power_button_device_ids[] = { + { ACPI_BUTTON_HID_POWER, 0 }, + { ACPI_BUTTON_HID_POWERF, 0 }, + { "", 0 }, +}; +MODULE_DEVICE_TABLE(acpi, tiny_power_button_device_ids); + +static void acpi_tiny_power_button_notify(acpi_handle handle, u32 event, void *data) +{ + kill_cad_pid(power_signal, 1); +} + +static void acpi_tiny_power_button_notify_run(void *not_used) +{ + acpi_tiny_power_button_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, NULL); +} + +static u32 acpi_tiny_power_button_event(void *not_used) +{ + acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_tiny_power_button_notify_run, NULL); + return ACPI_INTERRUPT_HANDLED; +} + +static int acpi_tiny_power_button_probe(struct platform_device *pdev) +{ + struct acpi_device *device; + acpi_status status; + + device = ACPI_COMPANION(&pdev->dev); + if (!device) + return -ENODEV; + + if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) { + status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, + acpi_tiny_power_button_event, + NULL); + } else { + status = acpi_install_notify_handler(device->handle, + ACPI_DEVICE_NOTIFY, + acpi_tiny_power_button_notify, + NULL); + } + if (ACPI_FAILURE(status)) + return -ENODEV; + + return 0; +} + +static void acpi_tiny_power_button_remove(struct platform_device *pdev) +{ + struct acpi_device *device = ACPI_COMPANION(&pdev->dev); + + if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) { + acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, + acpi_tiny_power_button_event); + } else { + acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_tiny_power_button_notify); + } + acpi_os_wait_events_complete(); +} + +static struct platform_driver acpi_tiny_power_button_driver = { + .probe = acpi_tiny_power_button_probe, + .remove = acpi_tiny_power_button_remove, + .driver = { + .name = "acpi-tiny-power-button", + .acpi_match_table = tiny_power_button_device_ids, + }, +}; + +module_platform_driver(acpi_tiny_power_button_driver); -- cgit v1.3.1