+ module-add-helper-function-for-reading-module_buildid.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: module: add helper function for reading module_buildid()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     module-add-helper-function-for-reading-module_buildid.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/module-add-helper-function-for-reading-module_buildid.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Petr Mladek <pmladek@suse.com>
Subject: module: add helper function for reading module_buildid()
Date: Fri, 28 Nov 2025 14:59:16 +0100

Add a helper function for reading the optional "build_id" member of struct
module.  It is going to be used also in ftrace_mod_address_lookup().

Use "#ifdef" instead of "#if IS_ENABLED()" to match the declaration of the
optional field in struct module.

Link: https://lkml.kernel.org/r/20251128135920.217303-4-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Cc: Aaron Tomlin <atomlin@atomlin.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkman <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Luis Chamberalin <mcgrof@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/module.h   |    9 +++++++++
 kernel/module/kallsyms.c |    9 ++-------
 2 files changed, 11 insertions(+), 7 deletions(-)

--- a/include/linux/module.h~module-add-helper-function-for-reading-module_buildid
+++ a/include/linux/module.h
@@ -748,6 +748,15 @@ static inline void __module_get(struct m
 	__mod ? __mod->name : "kernel";		\
 })
 
+static inline const unsigned char *module_buildid(struct module *mod)
+{
+#ifdef CONFIG_STACKTRACE_BUILD_ID
+	return mod->build_id;
+#else
+	return NULL;
+#endif
+}
+
 /* Dereference module function descriptor */
 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
 
--- a/kernel/module/kallsyms.c~module-add-helper-function-for-reading-module_buildid
+++ a/kernel/module/kallsyms.c
@@ -334,13 +334,8 @@ int module_address_lookup(unsigned long
 	if (mod) {
 		if (modname)
 			*modname = mod->name;
-		if (modbuildid) {
-#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
-			*modbuildid = mod->build_id;
-#else
-			*modbuildid = NULL;
-#endif
-		}
+		if (modbuildid)
+			*modbuildid = module_buildid(mod);
 
 		sym = find_kallsyms_symbol(mod, addr, size, offset);
 
_

Patches currently in -mm which might be from pmladek@suse.com are

kallsyms-clean-up-namebuf-initialization-in-kallsyms_lookup_buildid.patch
kallsyms-clean-up-modname-and-modbuildid-initialization-in-kallsyms_lookup_buildid.patch
module-add-helper-function-for-reading-module_buildid.patch
kallsyms-cleanup-code-for-appending-the-module-buildid.patch
kallsyms-bpf-rename-__bpf_address_lookup-to-bpf_address_lookup.patch
kallsyms-ftrace-set-module-buildid-in-ftrace_mod_address_lookup.patch
kallsyms-prevent-module-removal-when-printing-module-name-and-buildid.patch