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 --- lib/bsearch.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 lib/bsearch.c (limited to 'lib/bsearch.c') diff --git a/lib/bsearch.c b/lib/bsearch.c new file mode 100644 index 000000000..bf86aa66f --- /dev/null +++ b/lib/bsearch.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * A generic implementation of binary search for the Linux kernel + * + * Copyright (C) 2008-2009 Ksplice, Inc. + * Author: Tim Abbott + */ + +#include +#include +#include + +/* + * bsearch - binary search an array of elements + * @key: pointer to item being searched for + * @base: pointer to first element to search + * @num: number of elements + * @size: size of each element + * @cmp: pointer to comparison function + * + * This function does a binary search on the given array. The + * contents of the array should already be in ascending sorted order + * under the provided comparison function. + * + * Note that the key need not have the same type as the elements in + * the array, e.g. key could be a string and the comparison function + * could compare the string with the struct's name field. However, if + * the key and elements in the array are of the same type, you can use + * the same comparison function for both sort() and bsearch(). + */ +void *bsearch(const void *key, const void *base, size_t num, size_t size, cmp_func_t cmp) +{ + return __inline_bsearch(key, base, num, size, cmp); +} +EXPORT_SYMBOL(bsearch); +NOKPROBE_SYMBOL(bsearch); -- cgit v1.3.1