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/memory-notifier-error-inject.c | 49 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 lib/memory-notifier-error-inject.c (limited to 'lib/memory-notifier-error-inject.c') diff --git a/lib/memory-notifier-error-inject.c b/lib/memory-notifier-error-inject.c new file mode 100644 index 000000000..2c46dde59 --- /dev/null +++ b/lib/memory-notifier-error-inject.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include + +#include "notifier-error-inject.h" + +static int priority; +module_param(priority, int, 0); +MODULE_PARM_DESC(priority, "specify memory notifier priority"); + +static struct notifier_err_inject memory_notifier_err_inject = { + .actions = { + { NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_ONLINE) }, + { NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_OFFLINE) }, + {} + } +}; + +static struct dentry *dir; + +static int err_inject_init(void) +{ + int err; + + dir = notifier_err_inject_init("memory", notifier_err_inject_dir, + &memory_notifier_err_inject, priority); + if (IS_ERR(dir)) + return PTR_ERR(dir); + + err = register_memory_notifier(&memory_notifier_err_inject.nb); + if (err) + debugfs_remove_recursive(dir); + + return err; +} + +static void err_inject_exit(void) +{ + unregister_memory_notifier(&memory_notifier_err_inject.nb); + debugfs_remove_recursive(dir); +} + +module_init(err_inject_init); +module_exit(err_inject_exit); + +MODULE_DESCRIPTION("memory notifier error injection module"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Akinobu Mita "); -- cgit v1.3.1