struct X86_DBGKD_CONTROL_SET

typedef struct _X86_DBGKD_CONTROL_SET
{
     ULONG TraceFlag;
     ULONG Dr7;
     ULONG CurrentSymbolStart;
     ULONG CurrentSymbolEnd;
} X86_DBGKD_CONTROL_SET, *PX86_DBGKD_CONTROL_SET;

Windows Vista Kernel Structures