我正在关注 riscv.org 工具链构建指南。使用 qemu 运行本地构建的 rootfilesystem（带有busybox）和 Linux Kernel 进行仿真时，遇到以下错误：
使用本地构建的 root.bin 和内核映像运行 Qemu
danny@danny:~/test/riscv/work$ qemu-system-riscv -hda root-local.bin -kernel vmlinux-local -nographic
unassigned address was called?
with addr: 102000735F80006E
not implemented for riscv
使用 riscv.org 存储的 root.bin 和内核映像运行 Qemu
danny@danny:~/test/riscv/work$ qemu-system-riscv -hda root.bin -kernel vmlinux -nographic
[ 0.150000] io scheduler cfq registered (default)
[ 0.160000] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
[ 0.160000] serial8250: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[ 0.160000] TCP: cubic registered
[ 0.160000] htifbd: detected disk with ID 1
[ 0.160000] htifbd: adding htifbd0
[ 0.160000] VFS: Mounted root (ext2 filesystem) readonly on device 254:0.
[ 0.160000] devtmpfs: mounted
[ 0.160000] Freeing unused kernel memory: 64K (ffffffff80002000 - ffffffff80012000)
[ 0.200000] EXT2-fs (htifbd0): warning: mounting unchecked fs, running e2fsck is recommended
#uname -a
Linux ucbvax 3.14.15-g4073e84-dirty #4 Sun Jan 11 07:17:06 PST 2015 riscv GNU/Linux
如果使用从 riscv.org 下载的 root.bin 和 vmlinux 进行 qemu 测试，看起来还可以，但看不到busybox 启动消息并且终端无法停止：
使用各种组合测试了 qemu，结果如下：
**root.bin vmlinux RESULT**
local-built local-built Unassigned address was called ....
Downloaded Downloaded Seem OK but without busybox starting bar
local-built Downloaded Kernelpanic-not syncing:No working init found
Downloaded local-built Unassigned address was called ....
我们正在启动一个项目，为世界各地的 Maker 构建和制造 RISCV 硅芯片，并现在测试工具链，以便将 Ubuntu Core 和 Android 移植到 RISCV。知道可能出了什么问题吗？
谢谢。