oh, there is much much much code,it's too too too hard for me.

So,,,,,can i ask more question:use virt-manager create a domain,but with a result of "unsupported configuration:the ioh3420 controller is not supported in this qemu".since it's arm64 platform,and ioh3420 is a intel device.right?Why produce a intel device in arm64 platform?

So, can i delete the ioh3420 only by changing the code?info: i use the libvirt-2.0.0,virt-manager create doamin succeed;when i update to libvirt-3.2.0,the issue above happened. qemu is 2.3.0

Thanks!

--
Have a good day


> -----原始邮件-----
> 发件人: Michal Privoznik <mprivozn@redhat.com>
> 发送时间: 2018年4月26日 星期四
> 收件人: "李卓瑶" <lizhuoyao@hikdata.com>
> 抄送: libvirt-users <libvirt-users@redhat.com>, shengyizju@163.com
> 主题: Re: [libvirt-users] how xml generated
> 
> On 04/26/2018 09:50 AM, 李卓瑶 wrote:
> > Thanks for your reply
> > what i want to know is that why there are many devices in $domain.xml, actully , i choose nothing in virt-manager?
> > so, Do i need to look at qemuDomainDefineXMLFlags()?
> 
> Because we try to have 1:1 relationship between domain XML configuration
> and devices as seen by guest. Even when you don't select anything in
> virt-manager the domain will definitely have a PCI root controller,
> controller for disk bus (be it sata, scsi, ide, ..), then it'll also
> have a virtual NIC, some memory/cpu configuration, and so on.
> 
> In the code, these devices are added once XML is parsed by
> virDomainDefPostParseInternal(). Each driver can pass this xmlopt
> structure filled in with callbacks (take a look at
> virQEMUDriverCreateXMLConf()). So in the end, devices are added only
> after XML is parsed. However, it is not done all in one place. For
> instance, controllers are added during device address assignment, other
> devices are added in PostParse callbacks, and so on.
> 
> > hours ago, i thought it's qemuDomainCreateWithFlags.
> 
> No. This creates so called transient domains.
> 
> https://wiki.libvirt.org/page/VM_lifecycle#Transient_guest_domains_vs_Persistent_guest_domains
> 
> Michal