c - 从寄存器读取值时出现分段错误

Question

我正在尝试从寄存器中读取值，但它返回分段错误错误。但是，如果我分别传递基地址和偏移量，则此代码可以正常工作，但是当我传递组合地址时，它会返回错误。有人可以指导我解决这个问题。提前感谢>

   #define REG_READ(addr) (*(volatile unsigned int*)(addr))
    unsigned int Read(unsigned int Base_Address)
    {   unsigned int Base_Address_R = Base_Address;
        //unsigned int offset = os;
        printf("Reading Register");
        //UINTPTR  Base_Address_R = Reg_base_address_R;
        int *reg_addr;
        int fd;
        int value_return;
        int map_length = getpagesize();
        fd = open("/dev/mem", (O_RDWR | O_SYNC));
        reg_addr = mmap(NULL,map_length, PROT_READ|PROT_WRITE, MAP_SHARED,fd,Base_Address_R);
        if (reg_addr == MAP_FAILED)
        {
            printf("mmap failed");
            close(fd);
        }
        //REG_WRITE(reg_addr, offset,value);
        REG_READ(reg_addr);
        printf("Memory=%d",(*(volatile unsigned int*)(reg_addr)));
        value_return = (*(volatile unsigned int*)(reg_addr));
        munmap((void *)reg_addr, map_length);
        return value_return;
    }
    
    int main()
    {   printf("Main");
        Read(0xFD480000);
    }