QEMU FAQ
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标签：FAQ
持嵌套虚拟化
- 大多云平台都不支持嵌套虚拟化
- 裸金属服务器 支持虚拟化
- 参考
- GCP 嵌套虚拟化简介
- Intel Haswell+
- Sandy Bridge, Ivy Bridge 不可以
- AMD 不可以
- Intel Haswell+
- Cloud Provider Instances with KVM support
- GCP - 所有支持
- DO - 所有支持
- Azure Dv3, Ev3 - 4C16G+ - $140/mo
- Packet - 4C8G+ - ~$50/mo
- AWS
*.metal- 裸金属服务器 - 48CPU+
- GCP 嵌套虚拟化简介
RNG
建议默认添加，否则可能导致非常慢意外 Hang 住
-device virtio-rng-pci默认 /dev/random。 可自定义参数
-object rng-random,filename=/dev/hwrng,id=rng0 -device virtio-rng-pci,rng=rng0qemu-system-x86_64 -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-pci,rng=rng0,bus=pci.0,addr=0x7
环境检测
# KVM 要求 Intel VT, AMD-V
egrep '(vmx|svm)' /proc/cpuinfo
modprobe kvm
modprobe kvm-intel访问远程镜像
# apk add qemu-block-ssh
qemu -drive file=ssh://host/path/to/file,if=virtio,cache=noneqemu: uncaught target signal 4 (Illegal instruction) - core dumped
ppc64le 异常
qemu-s390x: warning: 'msa5-base' requires 'klmd-sha-512'
s390x 异常
virtfs
wiki.qemu.org/Documentation/9psetup
ProjectZero QEMU: virtfs permits guest to access entire host filesystem HN #13753950Hacker NewsHacker News #13753950Hacker News
convert 后无法启动
- 在 macOS 下从 qcow2 转换为 raw 后分区信息丢失
- Linux 未遇到这样的问题
- 转换后可使用 fdisk 检查分区信息
Overhead
Containerization vs. Virtualization – More on Overhead
硬件加速
开启硬件加速和不开启性能可能相差 10 倍+。
qemu-system-x86_64 -accel help- tcg - JIT 模式
- macOS - hvf, hax
- hvf 实现不是很完整，可能会出现无法运行的情况
- 如果加速有问题，尝试修改 smp 为 1
- Windows - hyper, hax
- Linux - kvm
USB
qemu-system-x86_64 \
-enable-kvm \
-M q35 \
-m 2G \
-usb -usbdevice host:16b2:1001 \
-usb -usbdevice host:0529:0001 \
-usbdevice tablet \
-net nic \
-net bridge,br=br0 \
-vga qxl \
-spice port=5930,disable-ticketing \
-device virtio-serial-pci \
-device virtserialport,chardev=spicechannel0,name=com.redhat.spice.0 \
-chardev spicevmc,id=spicechannel0,name=vdagent \
-drive file=/mnt/data/win-patch.img,if=virtio-accel kvm: failed to initialize kvm: Permission denied
addgroup $USER kvm鼠标偏移
-device usb-ehci,id=usb,bus=pci.0,addr=0x4 -device usb-mouse -device usb-tablet -device usb-kbdusb
usb2.0
- 兼容性更好
-device usb-ehci,id=usb,bus=pci.0,addr=0x4usb3.0
-device nec-usb-xhci,id=usb,bus=pci.0,addr=0x4Cannot enable HVF when guest CPU has EL3 enabled
- Exception Level 3 (EL3)
- 最高的特权级别
TBD
no scancode found for keysym 1185
no scancode found for keysym 65306关联信息
反向链接、本文链接的其他页面和外部资料。
参考资料
GitHub1 条
- qemu/qemu/docs/usb2.txtgithub.com/qemu/qemu/blob/master/docs/usb2.txt
Hacker News1 条
- Hacker News #13753950HN #13753950
其他外链7 条
- cloud.google.com/compute/docs/instances/nested-virtualization/overviewcloud.google.com/compute/docs/instances/nested-virtualization/overview
- cloudplatform.googleblog.com/2017/01/7-ways-we-harden-our-KVM-hypervisor-at-Google-Cloud-security-in-plaintext.htmlcloudplatform.googleblog.com/2017/01/7-ways-we-harden-our-KVM-hypervisor-at-Google-Cloud-security-in-plaintext.html
- ignite.readthedocs.io/en/stable/cloudproviderignite.readthedocs.io/en/stable/cloudprovider
- unix.stackexchange.com/a/251406/47774unix.stackexchange.com/a/251406/47774
- wiki.qemu.org/Documentation/9psetupwiki.qemu.org/Documentation/9psetup
- www.brightcomputing.com/blog/containerization-vs.-virtualization-more-on-overheadwww.brightcomputing.com/blog/containerization-vs.-virtualization-more-on-overhead
- www.qemu.org/docs/master/system/devices/vhost-user-rng.htmlwww.qemu.org/docs/master/system/devices/vhost-user-rng.html