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#define		PG_P			0x1ULL
#define		PG_RW			0x2ULL
GLOBAL VOID IdleTask(THREAD* pMe){   //given the thread pointer of myself
	U64 PML4,PDP,PD,Stk;
	THREAD* p;
	/*	alloc page and thread struct for proc task.
		just a stack at linear address 1TB,
		the lower address was in kernel space,
		and was set G attribute in MemInit */ 
	p = (THREAD*)AllocPageK(4096);
	PML4 = AllocPageK(4096);
	PDP = AllocPageK(4096);
	PD = AllocPageK(4096);
	Stk = AllocPageK(0x200000);
	if(p==NULL||PML4==NULL||PDP==NULL||PD==NULL){
		Printk(COLOR_FR, L"\nFailed to creat process task.");
		while(1);
	}
	CleanMem((U64)p,4096);
	CleanMem(PML4,4096);
	CleanMem(PDP,4096);
	CleanMem(PD,4096);
	((U64*)PML4)[0] = ((U64*)(pMe->Cr3))[0]|PG_RW|PG_P;  //lower 512G is the same as kernel.Though G is set,but it got error without this
	((U64*)PML4)[1] = PDP|PG_RW|PG_P;  //this entry is 512G to 1T
	((U64*)PDP)[511] = PD|PG_RW|PG_P;   //use the last items,so it will be at 1T
	((U64*)PD)[511] = Stk|PG_RW|PG_P;
	p->IntStk[0] = (U64)ProcTask;
	p->IntStk[1] = SELECTORC1;
	p->IntStk[2] = 0x1002ULL;      			//IOPL=1
	p->IntStk[3] = 0x10000000000ull - 8;  	//rsp = 1T - 8byte
	p->IntStk[4] = SELECTORD1;
	p->Cr3 = PML4;
.......
}

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((U64*)PD)[511] = Stk|PG_RW|PG_P;