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/interconnect/bulk.c | 159 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 drivers/interconnect/bulk.c (limited to 'drivers/interconnect/bulk.c') diff --git a/drivers/interconnect/bulk.c b/drivers/interconnect/bulk.c new file mode 100644 index 000000000..8b1d8a412 --- /dev/null +++ b/drivers/interconnect/bulk.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include + +/** + * of_icc_bulk_get() - get interconnect paths + * @dev: the device requesting the path + * @num_paths: the number of icc_bulk_data + * @paths: the table with the paths we want to get + * + * Returns 0 on success or negative errno otherwise. + */ +int __must_check of_icc_bulk_get(struct device *dev, int num_paths, + struct icc_bulk_data *paths) +{ + int ret, i; + + for (i = 0; i < num_paths; i++) { + paths[i].path = of_icc_get(dev, paths[i].name); + if (IS_ERR(paths[i].path)) { + ret = PTR_ERR(paths[i].path); + if (ret != -EPROBE_DEFER) + dev_err(dev, "of_icc_get() failed on path %s (%d)\n", + paths[i].name, ret); + paths[i].path = NULL; + goto err; + } + } + + return 0; + +err: + icc_bulk_put(i, paths); + + return ret; +} +EXPORT_SYMBOL_GPL(of_icc_bulk_get); + +/** + * icc_bulk_put() - put a list of interconnect paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table with the paths being put + */ +void icc_bulk_put(int num_paths, struct icc_bulk_data *paths) +{ + while (--num_paths >= 0) { + icc_put(paths[num_paths].path); + paths[num_paths].path = NULL; + } +} +EXPORT_SYMBOL_GPL(icc_bulk_put); + +/** + * icc_bulk_set_bw() - set bandwidth to a set of paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + * + * Returns 0 on success or negative errno otherwise. + */ +int icc_bulk_set_bw(int num_paths, const struct icc_bulk_data *paths) +{ + int ret = 0; + int i; + + for (i = 0; i < num_paths; i++) { + ret = icc_set_bw(paths[i].path, paths[i].avg_bw, paths[i].peak_bw); + if (ret) { + pr_err("icc_set_bw() failed on path %s (%d)\n", paths[i].name, ret); + return ret; + } + } + + return ret; +} +EXPORT_SYMBOL_GPL(icc_bulk_set_bw); + +/** + * icc_bulk_enable() - enable a previously disabled set of paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + * + * Returns 0 on success or negative errno otherwise. + */ +int icc_bulk_enable(int num_paths, const struct icc_bulk_data *paths) +{ + int ret, i; + + for (i = 0; i < num_paths; i++) { + ret = icc_enable(paths[i].path); + if (ret) { + pr_err("icc_enable() failed on path %s (%d)\n", paths[i].name, ret); + goto err; + } + } + + return 0; + +err: + icc_bulk_disable(i, paths); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_bulk_enable); + +/** + * icc_bulk_disable() - disable a set of interconnect paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + */ +void icc_bulk_disable(int num_paths, const struct icc_bulk_data *paths) +{ + while (--num_paths >= 0) + icc_disable(paths[num_paths].path); +} +EXPORT_SYMBOL_GPL(icc_bulk_disable); + +struct icc_bulk_devres { + struct icc_bulk_data *paths; + int num_paths; +}; + +static void devm_icc_bulk_release(struct device *dev, void *res) +{ + struct icc_bulk_devres *devres = res; + + icc_bulk_put(devres->num_paths, devres->paths); +} + +/** + * devm_of_icc_bulk_get() - resource managed of_icc_bulk_get + * @dev: the device requesting the path + * @num_paths: the number of icc_bulk_data + * @paths: the table with the paths we want to get + * + * Returns 0 on success or negative errno otherwise. + */ +int devm_of_icc_bulk_get(struct device *dev, int num_paths, struct icc_bulk_data *paths) +{ + struct icc_bulk_devres *devres; + int ret; + + devres = devres_alloc(devm_icc_bulk_release, sizeof(*devres), GFP_KERNEL); + if (!devres) + return -ENOMEM; + + ret = of_icc_bulk_get(dev, num_paths, paths); + if (!ret) { + devres->paths = paths; + devres->num_paths = num_paths; + devres_add(dev, devres); + } else { + devres_free(devres); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_of_icc_bulk_get); -- cgit v1.3.1