Host insane unsafe usage

host/Makefile

@@ -6,7 +6,7 @@ ccflags-y := -Wno-declaration-after-statement -std=gnu99
 all: hello.ko
 
 hello.ko: hello.c
-	make -C '/lib/modules/$(shell uname -r)/build' M='$(PWD)' modules
+	$(MAKE) -C '/lib/modules/$(shell uname -r)/build' M='$(PWD)' modules
 
 clean:
-	make -C '/lib/modules/$(shell uname -r)/build' M='$(PWD)' clean
+	$(MAKE) -C '/lib/modules/$(shell uname -r)/build' M='$(PWD)' clean

host/README.md

@@ -1,35 +1,3 @@
 # Host
 
-Simple things that can be demonstrated by inserting a module into the currently running host. Tested on Ubuntu 16.04.
-
-1. [hello](hello.c)
-
-## Rationale
-
-This method easier to setup, but it is not recommended for development, as:
-
-- it may break your system
-- you can't control which kernel version to use
-
-Use VMs instead.
-
-## Usage
-
-We only use it for super simple examples.
-
-Build, insert and remove a hello world module:
-
-    make
-
-    sudo insmod hello.ko
-
-    # Our module should be there.
-    sudo lsmod | grep hello
-
-    # Last message should be: init_module
-    dmest -T
-
-    sudo rmmod hello
-
-    # Last message should be: cleanup_module
-    dmest -T
+Minimal host build system sanity check example.

host/hello.c

@@ -1,13 +1,17 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 
-int init_module(void)
+static int myinit(void)
 {
-	printk(KERN_INFO "init_module\n");
+	pr_info("hello init\n");
 	return 0;
 }
 
-void cleanup_module(void)
+static void myexit(void)
 {
-	printk(KERN_INFO "cleanup_module\n");
+	pr_info("hello exit\n");
 }
+
+module_init(myinit)
+module_exit(myexit)
+MODULE_LICENSE("GPL");