Enable single register read/write.

Author: gz

kernel/src/arch/x86_64/gdb/mod.rs

@@ -106,7 +106,7 @@ pub fn event_loop(reason: KCoreStopReason) -> Result<(), KError> {
     loop {
         gdb_stm = match gdb_stm {
             GdbStubStateMachine::Idle(mut gdb_stm_inner) => {
-                trace!("GdbStubStateMachine::Idle");
+                //trace!("GdbStubStateMachine::Idle");
                 // This means we expect stuff on the serial line (from GDB)
                 // Let's read and react to it:
                 let conn = gdb_stm_inner.borrow_conn();

kernel/src/arch/x86_64/gdb/single_thread_ops.rs

@@ -43,6 +43,7 @@ impl SingleThreadOps for KernelDebugger {
         &mut self,
         regs: &mut gdbstub_arch::x86::reg::X86_64CoreRegs,
     ) -> TargetResult<(), Self> {
+        trace!("read_registers");
         let kcb = super::super::kcb::get_kcb();
         if let Some(saved) = &kcb.arch.save_area {
             // RAX, RBX, RCX, RDX, RSI, RDI, RBP, RSP, r8-r15
@@ -271,13 +272,11 @@ impl SingleThreadOps for KernelDebugger {
     }
 
     fn support_single_register_access(&mut self) -> Option<SingleRegisterAccessOps<(), Self>> {
-        //Some(self)
-        None
+        Some(self)
     }
 
     fn support_single_step(&mut self) -> Option<SingleThreadSingleStepOps<Self>> {
         Some(self)
-        //None
     }
 }