typedef struct _KTSS64
{
    unsigned long Reserved0;
    unsigned __int64 Rsp0;
    unsigned __int64 Rsp1;
    unsigned __int64 Rsp2;
    unsigned __int64 Ist[8];
    unsigned __int64 Reserved1;
    unsigned short Reserved2;
    unsigned short IoMapBase;
} KTSS64, *PKTSS64;