首先使用 grep --color -E "vmx|svm" /proc/cpuinfo 检查 cpu 能不能支持虚拟化，注意 biso 里面要开启虚拟化。

内核开启相应选项

[*] Virtualization  --->

    <*>   Kernel-based Virtual Machine (KVM) support

[*] Virtualization  --->

    <M>   KVM for Intel processors support

[*] Virtualization  --->

    <M>   KVM for AMD processors support

[*] Virtualization  --->

    <*>   Host kernel accelerator for virtio net

Device Drivers  --->

    [*] Network device support  --->

        [*]   Network core driver support

        <*>   Universal TUN/TAP device driver support

[*] Networking support  --->

        Networking options  --->

            <*> The IPv6 protocol

            <*> 802.1d Ethernet Bridging

Kernel hacking  --->

        Compile-time checks and compiler options  --->

            [*] Debug Filesystem

File systems  --->

    <*> The Extended 4 (ext4) filesystem

    [*]   Ext4 Security Labels

然后根据需要 qemu 使用的客户端，修改 make.conf

QEMU_SOFTMMU_TARGETS="arm x86_64 i386"

QEMU_USER_TARGETS="x86_64 arm armeb i386"

增加 qemu 的 USE ： accessibility gtk ncurses python sdl spice usbredir

然后安装 qemu: emerge --ask app-emulation/qemu

加入 kvm组： gpasswd -a kvm

安装 virt-manager: emerge -v virt-manager，注意开启 USE： gtk

配置让普通用户使用 qemu:

groupadd libvirt

usermod -a -G libvirt

vim /etc/libvirt/libvirtd.conf

unix_sock_group = "libvirt"

unix_sock_ro_perms = "0777"

unix_sock_rw_perms = "0770"

退出重新登录后，rc-service libvirtd restart 重启服务.