From 2e04c96fad8c657e283dcf7da2ebdaa6da3a5eeb Mon Sep 17 00:00:00 2001
From: Ciro Santilli <ciro.santilli@gmail.com>
Date: Mon, 13 Nov 2017 15:48:25 +0000
Subject: [PATCH] MODULE_VERSION and srcversion

---
 kernel_config_fragment         |  3 +++
 kernel_module/README.md        |  1 +
 kernel_module/module_version.c | 28 ++++++++++++++++++++++++++++
 kernel_module/vermagic.c       |  6 ++++--
 4 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 kernel_module/module_version.c

diff --git a/kernel_config_fragment b/kernel_config_fragment
index 0f3b62a..1a0ada4 100644
--- a/kernel_config_fragment
+++ b/kernel_config_fragment
@@ -1,6 +1,9 @@
 # Changes to this file are automatically trigger kernel reconfigures
 # even without using the linux-reconfigure target.
 
+CONFIG_MODULE_SRCVERSION_ALL=y
+
+# GDB debugging.
 CONFIG_DEBUG_FS=y
 CONFIG_DEBUG_INFO=y
 CONFIG_DEBUG_KERNEL=y
diff --git a/kernel_module/README.md b/kernel_module/README.md
index 51fcb55..5e00018 100644
--- a/kernel_module/README.md
+++ b/kernel_module/README.md
@@ -9,6 +9,7 @@
     1.  [params](params.c)
     1.  [vermagic](vermagic.c)
     1.  [vermagic_fail](vermagic_fail.c)
+    1.  [module_version](module_version.c)
 1.  Pseudo filesystems
     1.  [debugfs](debugfs.c)
     1.  [procfs](procfs.c)
diff --git a/kernel_module/module_version.c b/kernel_module/module_version.c
new file mode 100644
index 0000000..aac8189
--- /dev/null
+++ b/kernel_module/module_version.c
@@ -0,0 +1,28 @@
+/*
+https://stackoverflow.com/questions/4839024/how-to-find-the-version-of-a-compiled-kernel-module/42556565#42556565
+
+    insmod /module_version.ko
+    cat /sys/modules/module_version/version
+    # => 1.0
+    cat /sys/module/module_version/srcversion
+    # => AB0F06618BC3A36B687CDC5
+    modinfo /module_version.ko | grep -E '^(src|)version'
+    # => version:        1.0
+    # => srcversion:     AB0F06618BC3A36B687CDC5
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+static int myinit(void)
+{
+	pr_info(__FILE__ "\n");
+	return 0;
+}
+
+static void myexit(void) {}
+
+module_init(myinit)
+module_exit(myexit)
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");
diff --git a/kernel_module/vermagic.c b/kernel_module/vermagic.c
index d4baff1..aa00b52 100644
--- a/kernel_module/vermagic.c
+++ b/kernel_module/vermagic.c
@@ -1,7 +1,9 @@
 /*
     insmod /vermagic.ko
     # => 4.9.6 SMP mod_unload modversions
-TODO how to get the vermagic from running kernel from userland? <https://lists.kernelnewbies.org/pipermail/kernelnewbies/2012-October/006306.html>
+
+TODO how to get the vermagic from running kernel from userland?
+<https://lists.kernelnewbies.org/pipermail/kernelnewbies/2012-October/006306.html>
 */
 
 #include <linux/module.h>
@@ -10,7 +12,7 @@ TODO how to get the vermagic from running kernel from userland? <https://lists.k
 
 static int myinit(void)
 {
-	pr_info(VERMAGIC_STRING "\n");
+	pr_info(__FILE__ "\n");
 	return 0;
 }