操作系统实验challenge1_1

ssize_t sys_user_printbacktrace(uint64 depth){
   

    // uint64 fpp = current->trapframe->regs.s0;
    // for(int i=0;i<depth;i++){
   
      // uint64 fpp = current->trapframe->regs.s0;
      // uint64 raa = (fpp-8);
      // uint64 yuanlaifpp = fpp-16;
      // sprint("fpp %p  raa  %p  yuanlaifpp  %p \n",fpp,raa,yuanlaifpp);
      // uint64 values0 = (*((uint64 * )fpp)); 
      // uint64 valueraa = (*((uint64 * )raa));