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/power/reset/syscon-poweroff.c | 98 +++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 drivers/power/reset/syscon-poweroff.c (limited to 'drivers/power/reset/syscon-poweroff.c') diff --git a/drivers/power/reset/syscon-poweroff.c b/drivers/power/reset/syscon-poweroff.c new file mode 100644 index 000000000..203936f4c --- /dev/null +++ b/drivers/power/reset/syscon-poweroff.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Generic Syscon Poweroff Driver + * + * Copyright (c) 2015, National Instruments Corp. + * Author: Moritz Fischer + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct syscon_poweroff_data { + struct regmap *map; + u32 offset; + u32 value; + u32 mask; +}; + +static int syscon_poweroff(struct sys_off_data *off_data) +{ + struct syscon_poweroff_data *data = off_data->cb_data; + + /* Issue the poweroff */ + regmap_update_bits(data->map, data->offset, data->mask, data->value); + + mdelay(1000); + + pr_emerg("Unable to poweroff system\n"); + + return NOTIFY_DONE; +} + +static int syscon_poweroff_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct syscon_poweroff_data *data; + int mask_err, value_err; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); + if (IS_ERR(data->map)) { + data->map = syscon_node_to_regmap(dev->parent->of_node); + if (IS_ERR(data->map)) { + dev_err(dev, "unable to get syscon"); + return PTR_ERR(data->map); + } + } + + if (of_property_read_u32(dev->of_node, "offset", &data->offset)) { + dev_err(dev, "unable to read 'offset'"); + return -EINVAL; + } + + value_err = of_property_read_u32(dev->of_node, "value", &data->value); + mask_err = of_property_read_u32(dev->of_node, "mask", &data->mask); + if (value_err && mask_err) { + dev_err(dev, "unable to read 'value' and 'mask'"); + return -EINVAL; + } + + if (value_err) { + /* support old binding */ + data->value = data->mask; + data->mask = 0xFFFFFFFF; + } else if (mask_err) { + /* support value without mask*/ + data->mask = 0xFFFFFFFF; + } + + return devm_register_sys_off_handler(&pdev->dev, + SYS_OFF_MODE_POWER_OFF, + SYS_OFF_PRIO_DEFAULT, + syscon_poweroff, data); +} + +static const struct of_device_id syscon_poweroff_of_match[] = { + { .compatible = "syscon-poweroff" }, + {} +}; + +static struct platform_driver syscon_poweroff_driver = { + .probe = syscon_poweroff_probe, + .driver = { + .name = "syscon-poweroff", + .of_match_table = syscon_poweroff_of_match, + }, +}; +builtin_platform_driver(syscon_poweroff_driver); -- cgit v1.3.1