Allow catching int3

src/arch/x86_64/interrupt/exception.rs

@@ -49,8 +49,15 @@ interrupt_stack!(non_maskable, stack, {
 
 interrupt_stack!(breakpoint, stack, {
     println!("Breakpoint trap");
-    stack.dump();
-    ksignal(SIGTRAP);
+
+    let guard = ptrace::set_process_regs(stack);
+
+    if ptrace::breakpoint_callback(PTRACE_STOP_BREAKPOINT, None).is_none() {
+        drop(guard);
+
+        stack.dump();
+        ksignal(SIGTRAP);
+    }
 });
 
 interrupt_stack!(overflow, stack, {