Task4: Add simple module file

task4-simple-kernel-module/Makefile

@@ -0,0 +1,13 @@
+# obj-m is predefined kbuild variable. used for modules.
+ifneq ($(KERNELRELEASE),)
+obj-m := hello.o
+else
+
+KDIR ?= /lib/modules/$(shell uname -r)/build
+
+all:
+	$(MAKE) -Wall -C $(KDIR)  M=$(shell pwd) modules
+
+clean:
+	$(MAKE) -C $(KDIR)  M=$(shell pwd) clean
+endif

task4-simple-kernel-module/hello.c

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) Copyright 2022
+ * Author: Roman Kulchytskyi <kulch.roman@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Roman Kulchytskyi");
+MODULE_DESCRIPTION("Some description");
+MODULE_VERSION("0.1");
+
+static int first = 100;
+module_param(first, int, 0444);
+MODULE_PARM_DESC(first, "A first integer");
+
+static int second = 99;
+module_param(second, int, 0444);
+MODULE_PARM_DESC(second, "A second integer");
+
+static int __init hello_init(void)
+{
+	pr_notice("Hello, world\n");
+	pr_info("%d + %d = %d", first, second, first + second);
+	pr_info("%d - %d = %d", first, second, first - second);
+	pr_info("%d * %d= %d", first, second, first * second);
+	return 0;
+}
+
+static void __exit hello_exit(void)
+{
+	pr_notice("Goodbye\n");
+}
+
+module_init(hello_init);
+module_exit(hello_exit);