Centos7 KVM编译安装Qemu4.0.0和libvirt5.4.0教程，解决多个问题
经过几天的努力，终于完成安装了！现在记录一下，方便以后重装KVM时使用。
安装版本：
qemu-4.0.0.tar.xz
libvirt-5.4.0.tar.xz
官网下载地址
QEMU
https://download.qemu.org/
Libvirt
https://libvirt.org/sources/
首先更新一下系统
yum update -y
然后重启
reboot
卸载旧内核
yum remove kernel -y
现在开始进行安装：
首先安装qemu kvm
安装依赖包
yum -y install gcc gcc-c++ automake libtool zlib-devel glib2-devel bzip2-devel libuuid-devel spice-protocol spice-server-devel usbredir-devel libaio-devel
在官网地址下载好qemu-4.0.0.tar.xz包解压并进入qemu-4.0.0目录
tar xvJf qemu-4.0.0.tar.xz
cd qemu-4.0.0
首先配置，改变一下编译安装的目录，方便以后使用
./configure --prefix=/usr
配置完成后进行安装
make && make install
安装完成后，做链接
ln -sf /usr/bin/qemu-system-x86_64 /usr/bin/qemu-kvm
ln -sf /usr/bin/qemu-system-x86_64 /usr/libexec/qemu-kvm
然后查看是否成功
qemu-img --version
qemu-kvm --version
现在开始安装libvirt
先安装一下virt-install工具，不然后面安装就会出现某些问题。
yum -y install virt-install
完成后，开始安装相关依赖包
yum -y install libnl-devel libxml2-devel yajl-devel device-mapper-devel libpciaccess-devel gnutls* libxslt
在官网地址下载好libvirt-5.4.0.tar.xz包解压并进入libvirt-5.4.0目录
tar xvJf libvirt-5.4.0.tar.xz
cd libvirt-5.4.0
autogen.sh脚本提供了“--system”参数，可保持对操作系统发型版中安装可执行程序和共享库的目录的一致性：
./autogen.sh --system
然后进行安装
make && make install
完成先安装一下管理工具包和桥接
yum -y install virt-manager virt-viewer bridge-utils
yum -y install libXdmcp libxkbfile xorg-x11-xkb-utils
完成后配置一下br0桥接
cd /etc/sysconfig/network-scripts
cp ifcfg-eth0 ifcfg-br0
sed -i 's/^IPADDR=/#IPADDR=/g' ifcfg-eth0
sed -i 's/^GATEWAY/#GATEWAY/g' ifcfg-eth0
sed -i 's/^IPV6ADDR=/#IPV6ADDR=/g' ifcfg-eth0
sed -i 's/^IPV6_DEFAULTGW=/#IPV6_DEFAULTGW=/g' ifcfg-eth0
echo BRIDGE="br0">>ifcfg-eth0
sed -i 's/TYPE="Ethernet"/TYPE="Bridge"/g' ifcfg-br0
sed -i 's/DEVICE="eth0"/DEVICE="br0"/g' ifcfg-br0
sed -i 's/NAME="eth0"/NAME="br0"/g' ifcfg-br0
sed -i 's/^UUID=/#UUID=/g' ifcfg-br0
重启网络
systemctl restart network
由于编译安装libvirt的版本无法使用systemctl管理，我们就拷贝一下libvirtd.service到/etc/systemd/system/，这样就可以使用systemctl管理了：
cp /usr/lib/systemd/system/libvirtd.service /etc/systemd/system/libvirtd.service
然后启动libvirt，并设置开机启动
systemctl start libvirtd.service #启动libvirt
systemctl enable libvirtd.service #开机启动libvirt
还需要安装一下防火墙
yum install firewalld
systemctl start firewalld
systemctl enable firewalld
最后测试一下
virsh list --all
没显示错误就成功了。
XMing，virt-manager管理工具
ubuntu编译时出错，
root@yuanjibin:/home/yuanjibin# cd libvirt-1.3.5
root@yuanjibin:/home/yuanjibin/libvirt-1.3.5# make
make all-recursive
make[1]: Entering directory '/home/yuanjibin/libvirt-1.3.5'
Making all in .
make[2]: Entering directory '/home/yuanjibin/libvirt-1.3.5'
make[2]: Leaving directory '/home/yuanjibin/libvirt-1.3.5'
Making all in gnulib/lib
make[2]: Entering directory '/home/yuanjibin/libvirt-1.3.5/gnulib/lib'
make all-am
make[3]: Entering directory '/home/yuanjibin/libvirt-1.3.5/gnulib/lib'
CC fseeko.lo
fseeko.c: In function 'rpl_fseeko':
fseeko.c:110:4: error: #error "Please port gnulib fseeko.c to your platform! Look at the code in fseeko.c, then report this to bug-gnulib."
110 | #error "Please port gnulib fseeko.c to your platform! Look at the code in fseeko.c, then report this to bug-gnulib."
| ^~~~~
make[3]: *** [Makefile:2259: fseeko.lo] Error 1
make[3]: Leaving directory '/home/yuanjibin/libvirt-1.3.5/gnulib/lib'
make[2]: *** [Makefile:2011: all] Error 2
make[2]: Leaving directory '/home/yuanjibin/libvirt-1.3.5/gnulib/lib'
make[1]: *** [Makefile:2004: all-recursive] Error 1
make[1]: Leaving directory '/home/yuanjibin/libvirt-1.3.5'
make: *** [Makefile:1901: all] Error 2
启动域时出错: 内部错误：qemu unexpectedly closed the monitor: libvirt: 错误 : 无法执行二进制文件 /usr/libexec/qemu-kvm: 权限不够
Traceback (most recent call last):
File "/usr/share/virt-manager/virtManager/asyncjob.py", line 89, in cb_wrapper
callback(asyncjob, *args, **kwargs)
File "/usr/share/virt-manager/virtManager/asyncjob.py", line 125, in tmpcb
callback(*args, **kwargs)
File "/usr/share/virt-manager/virtManager/libvirtobject.py", line 82, in newfn
ret = fn(self, *args, **kwargs)
File "/usr/share/virt-manager/virtManager/domain.py", line 1506, in startup
self._backend.create()
File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1080, in create
if ret == -1: raise libvirtError ('virDomainCreate() failed', dom=self)
libvirtError: 内部错误：qemu unexpectedly closed the monitor: libvirt: 错误 : 无法执行二进制文件 /usr/libexec/qemu-kvm: 权限不够
更新完成后 出现这个错误能帮忙看下嘛？
权限不够是不是没有关闭selinux，试试把这个关了