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/layouts/fixed-layout.c | 58 ++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 drivers/nvmem/layouts/fixed-layout.c (limited to 'drivers/nvmem/layouts/fixed-layout.c') diff --git a/drivers/nvmem/layouts/fixed-layout.c b/drivers/nvmem/layouts/fixed-layout.c new file mode 100644 index 000000000..635d448b3 --- /dev/null +++ b/drivers/nvmem/layouts/fixed-layout.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2026 Bootlin + * + * Authors: Mathieu Dubois-Briand + */ + +#include +#include + +#include "../internals.h" + +static int fixed_layout_add_cells(struct nvmem_layout *layout) +{ + struct device_node *np; + int ret; + + np = of_nvmem_layout_get_container(layout->nvmem); + if (!np) + return -ENOENT; + + ret = nvmem_add_cells_from_dt(layout->nvmem, np); + of_node_put(np); + + return ret; +} + +static int fixed_layout_probe(struct nvmem_layout *layout) +{ + layout->add_cells = fixed_layout_add_cells; + + return nvmem_layout_register(layout); +} + +static void fixed_layout_remove(struct nvmem_layout *layout) +{ + nvmem_layout_unregister(layout); +} + +static const struct of_device_id fixed_layout_of_match_table[] = { + { .compatible = "fixed-layout", }, + {}, +}; + +static struct nvmem_layout_driver fixed_layout_layout = { + .driver = { + .name = "fixed-layout", + .of_match_table = fixed_layout_of_match_table, + }, + .probe = fixed_layout_probe, + .remove = fixed_layout_remove, +}; +module_nvmem_layout_driver(fixed_layout_layout); + +MODULE_AUTHOR("Mathieu Dubois-Briand"); +MODULE_LICENSE("GPL"); +MODULE_DEVICE_TABLE(of, fixed_layout_of_match_table); +MODULE_DESCRIPTION("NVMEM fixed-layout driver"); -- cgit v1.3.1