我正在尝试使用 QEMU 模拟 ARM 架构。我的主机操作系统是 ubuntu 16.04，模拟机内的来宾操作系统也是 ubuntu 16.04。以下是我正在关注的教程：
sudo apt-get install qemu-system-arm qemu-efi
dd if=/dev/zero of=flash0.img bs=1M count=64
dd if=/usr/share/qemu-efi/QEMU_EFI.fd of=flash0.img conv=notrunc
dd if=/dev/zero of=flash1.img bs=1M count=64
sudo qemu-system-arm -m 1024 -cpu cortex-a57 -M virt -nographic -pflash flash0.img -pflash flash1.img -drive if=none,file=xenial-server-cloudimg-arm64-uefi1.img,id=hd0 -device virtio-blk-device,drive=hd0 -netdev type=tap,id=net0 -device virtio-net-device,netdev=net0,mac=$randmac
这给了我以下错误：
WARNING: Image format was not specified for 'flash0.img' and probing guessed raw.
Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted.
Specify …