Stage 1：使用debootstrap制作64位組件
盡管內核工作於64位模式，但系統大多數組件仍舊處於32位模式下。
我們的目標是引入Debian 9 arm64，自然會想到使用debootstrap。
在樹莓派上，給一張SD卡分兩個區：
- 一個在前面，大小100M左右，使用
mkfs.vfat，類型為W95 FAT32 - 一個占用后面所有的空間，視
/boot/cmdline.txt中rootfstype的設置選擇分區格式
然后（在樹莓派上）開干：
sudo debootstrap --verbose --arch=arm64 stretch . https://mirrors.ustc.edu.cn/debian/
編輯sources.list：
deb http://mirrors.ustc.edu.cn/debian/ stretch main
deb http://mirrors.ustc.edu.cn/archive.raspberrypi.org/ jessie main non-free contrib
apt.conf：
APT::Default-Release "stretch";
Chroot和之前的准備工作：
sudo mount -t proc proc proc
sudo mount -t sysfs sysfs sys
sudo mount -o bind /dev dev
sudo chroot .
視具體情況安裝軟件包。
apt install hostapd wpasupplicant udhcpd screen dnsmasq sudo openssh-server firmware-brcm80211 ...
- firmware-brcm80211：使系統識別樹莓派3板載網卡
- hostapd,udhcpd,dnsmasq：啟動AP必備
- wpasupplicant：用於連接Wifi熱點
- openssh-server：SSH服務器
- sudo,screen：這兩個想必大家都聽說過吧……
退出Chroot環境，復制配置文件及其它核心組件，例如：
/boot
/lib/modules
/etc/passwd
/etc/shadow
/etc/sudoers
/etc/hostapd
/etc/default
/etc/udhcpd.conf
/etc/udev/
/etc/dnsmasq.conf
...
成功啟動。
但是有煩人的提示（如果沒有就無視掉吧……）：
ERROR: ld.so: object '/usr/lib/arm-linux-gnueabihf/libarmmem.so' from /etc/ld.so.preload cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
解決方案顯而易見：
sudo mv /etc/ld.so.preload /etc/ld.so.preload.bak
sudo touch /etc/ld.so.preload
如果你使用了一張新的SD卡，記得編輯/etc/fstab！
Stage 2：站穩腳跟
*執行apt-get update，提示：
Ign:1 https://mirrors.ustc.edu.cn/debian stretch InRelease
Get:2 https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease [22.9 kB]
Hit:2 https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease
Get:3 https://mirrors.ustc.edu.cn/debian stretch Release [113 kB]
Hit:3 https://mirrors.ustc.edu.cn/debian stretch Release
Can't locate Storable.pm in @INC (you may need to install the Storable module) (@INC contains: /etc/perl /usr/local/lib/aarch64-linux-gnu/perl/5.24.1 /usr/local/share/perl/5.24.1 /usr/lib/aarch64-linux-gnu/perl5/5.24 /usr/share/perl5 /usr/lib/aarch64-linux-gnu/perl/5.24 /usr/share/perl/5.24 /usr/local/lib/site_perl /usr/lib/aarch64-linux-gnu/perl-base) at /usr/bin/apt-show-versions line 37.
BEGIN failed--compilation aborted at /usr/bin/apt-show-versions line 37.
Reading package lists... Done
N: Skipping acquire of configured file 'main/binary-arm64/Packages' as repository 'https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease' doesn't support architecture 'arm64'
N: Skipping acquire of configured file 'non-free/binary-arm64/Packages' as repository 'https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease' doesn't support architecture 'arm64'
N: Skipping acquire of configured file 'contrib/binary-arm64/Packages' as repository 'https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease' doesn't support architecture 'arm64'
N: Skipping acquire of configured file 'ui/binary-arm64/Packages' as repository 'https://mirrors.ustc.edu.cn/archive.raspberrypi.org jessie InRelease' doesn't support architecture 'arm64'
E: Problem executing scripts APT::Update::Post-Invoke-Success 'test -x /usr/bin/apt-show-versions || exit 0 ; apt-show-versions -i'
E: Sub-process returned an error code
筆者嘗試執行sudo apt-get install apt-show-versions，問題解決。
小結
路曼曼其修遠兮，吾將上下而求索。
目前整個系統僅僅只是能用，還有許多不完美的地方。
更新
4.12的內核可以使樹莓派工作得更好，ACT燈和VCHI將正常工作。