Fixes #18 -- call the kernel's BUG macro when we panic

.travis.yml

@@ -31,9 +31,12 @@ script:
     - cd $MODULE_DIR
     - RUST_TARGET_PATH="$(pwd)/.." cargo xbuild --target x86_64-linux-kernel-module
     - make
+    - sudo dmesg -C
     - sudo insmod "${MODULE}.ko"
     - sudo rmmod "$MODULE"
 
+after_failure:
+    - dmesg
 
 notifications:
     email: false

src/helpers.c

@@ -1,6 +1,12 @@
+#include <linux/bug.h>
 #include <linux/printk.h>
 
 int printk_helper(const unsigned char *s, int len)
 {
-	return printk(KERN_INFO "%.*s", len, (const char *)s);
+    return printk(KERN_INFO "%.*s", len, (const char *)s);
+}
+
+void bug_helper(void)
+{
+    BUG();
 }

src/lib.rs

@@ -64,12 +64,18 @@ pub trait KernelModule: Sized {
     fn init() -> KernelResult<Self>;
 }
 
+extern "C" {
+    fn bug_helper() -> !;
+}
+
 #[lang = "eh_personality"]
 extern "C" fn eh_personality() {}
 
 #[lang = "panic_fmt"]
 extern "C" fn panic_fmt() -> ! {
-    loop {}
+    unsafe {
+        bug_helper();
+    }
 }
 
 #[global_allocator]