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 --- include/trace/events/module.h | 134 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 include/trace/events/module.h (limited to 'include/trace/events/module.h') diff --git a/include/trace/events/module.h b/include/trace/events/module.h new file mode 100644 index 000000000..e5a006be9 --- /dev/null +++ b/include/trace/events/module.h @@ -0,0 +1,134 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Because linux/module.h has tracepoints in the header, and ftrace.h + * used to include this file, define_trace.h includes linux/module.h + * But we do not want the module.h to override the TRACE_SYSTEM macro + * variable that define_trace.h is processing, so we only set it + * when module events are being processed, which would happen when + * CREATE_TRACE_POINTS is defined. + */ +#ifdef CREATE_TRACE_POINTS +#undef TRACE_SYSTEM +#define TRACE_SYSTEM module +#endif + +#if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_MODULE_H + +#include + +#ifdef CONFIG_MODULES + +struct module; + +#define show_module_flags(flags) __print_flags(flags, "", \ + { (1UL << TAINT_PROPRIETARY_MODULE), "P" }, \ + { (1UL << TAINT_OOT_MODULE), "O" }, \ + { (1UL << TAINT_FORCED_MODULE), "F" }, \ + { (1UL << TAINT_CRAP), "C" }, \ + { (1UL << TAINT_UNSIGNED_MODULE), "E" }) + +TRACE_EVENT(module_load, + + TP_PROTO(struct module *mod), + + TP_ARGS(mod), + + TP_STRUCT__entry( + __field( unsigned int, taints ) + __string( name, mod->name ) + ), + + TP_fast_assign( + __entry->taints = mod->taints; + __assign_str(name); + ), + + TP_printk("%s %s", __get_str(name), show_module_flags(__entry->taints)) +); + +TRACE_EVENT(module_free, + + TP_PROTO(struct module *mod), + + TP_ARGS(mod), + + TP_STRUCT__entry( + __string( name, mod->name ) + ), + + TP_fast_assign( + __assign_str(name); + ), + + TP_printk("%s", __get_str(name)) +); + +#ifdef CONFIG_MODULE_UNLOAD +/* trace_module_get/put are only used if CONFIG_MODULE_UNLOAD is defined */ + +DECLARE_EVENT_CLASS(module_refcnt, + + TP_PROTO(struct module *mod, unsigned long ip), + + TP_ARGS(mod, ip), + + TP_STRUCT__entry( + __field( unsigned long, ip ) + __field( int, refcnt ) + __string( name, mod->name ) + ), + + TP_fast_assign( + __entry->ip = ip; + __entry->refcnt = atomic_read(&mod->refcnt); + __assign_str(name); + ), + + TP_printk("%s call_site=%ps refcnt=%d", + __get_str(name), (void *)__entry->ip, __entry->refcnt) +); + +DEFINE_EVENT(module_refcnt, module_get, + + TP_PROTO(struct module *mod, unsigned long ip), + + TP_ARGS(mod, ip) +); + +DEFINE_EVENT(module_refcnt, module_put, + + TP_PROTO(struct module *mod, unsigned long ip), + + TP_ARGS(mod, ip) +); +#endif /* CONFIG_MODULE_UNLOAD */ + +TRACE_EVENT(module_request, + + TP_PROTO(char *name, bool wait, unsigned long ip), + + TP_ARGS(name, wait, ip), + + TP_STRUCT__entry( + __field( unsigned long, ip ) + __field( bool, wait ) + __string( name, name ) + ), + + TP_fast_assign( + __entry->ip = ip; + __entry->wait = wait; + __assign_str(name); + ), + + TP_printk("%s wait=%d call_site=%ps", + __get_str(name), (int)__entry->wait, (void *)__entry->ip) +); + +#endif /* CONFIG_MODULES */ + +#endif /* _TRACE_MODULE_H */ + +/* This part must be outside protection */ +#include -- cgit v1.3.1