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/nvmem/internals.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 drivers/nvmem/internals.h (limited to 'drivers/nvmem/internals.h') diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h new file mode 100644 index 000000000..4e610deea --- /dev/null +++ b/drivers/nvmem/internals.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_NVMEM_INTERNALS_H +#define _LINUX_NVMEM_INTERNALS_H + +#include +#include +#include + +/* Hold pointers to callbacks owned by the nvmem provider module. */ +struct nvmem_operations { + nvmem_reg_read_t reg_read; + nvmem_reg_write_t reg_write; +}; + +struct nvmem_device { + struct module *owner; + struct device dev; + int stride; + int word_size; + int id; + struct kref refcnt; + size_t size; + bool read_only; + bool root_only; + int flags; + enum nvmem_type type; + struct bin_attribute eeprom; + struct device *base_dev; + struct list_head cells; + void (*fixup_dt_cell_info)(struct nvmem_device *nvmem, + struct nvmem_cell_info *cell); + const struct nvmem_keepout *keepout; + unsigned int nkeepout; + struct gpio_desc *wp_gpio; + struct nvmem_layout *layout; + struct nvmem_operations *ops; + void *priv; + bool sysfs_cells_populated; +}; + +int nvmem_add_cells_from_dt(struct nvmem_device *nvmem, struct device_node *np); + +#if IS_ENABLED(CONFIG_OF) +int nvmem_layout_bus_register(void); +void nvmem_layout_bus_unregister(void); +int nvmem_populate_layout(struct nvmem_device *nvmem); +void nvmem_destroy_layout(struct nvmem_device *nvmem); +#else /* CONFIG_OF */ +static inline int nvmem_layout_bus_register(void) +{ + return 0; +} + +static inline void nvmem_layout_bus_unregister(void) {} + +static inline int nvmem_populate_layout(struct nvmem_device *nvmem) +{ + return 0; +} + +static inline void nvmem_destroy_layout(struct nvmem_device *nvmem) { } +#endif /* CONFIG_OF */ + +#endif /* ifndef _LINUX_NVMEM_INTERNALS_H */ -- cgit v1.3.1