On 18/05/21 14:22, Thomas Parrott wrote:
Due to QEMU moving towards a QMP configuration mechanism and away from
config file support, the LXD team are currently in the process of
migrating to using QMP to add devices to VMs (so that we can support the
use of QEMU 6.0).
If the only issue you have is with -spice, that's just a bug that we
need to fix. -readconfig is still supposed to work, even though
-writeconfig is deprecated and I'd like to remove it as soon as 6.1.
In particular, the issue you reported below is not a bug. Devices that
are added after startup are considered hotplugged, and the boot index
list is frozen until the next reset. QMP-based configuration of
coldplugged devices is in the works, but unfortunately it is not yet ready.
Paolo
Currently we are using the `-S` flag to freeze CPU at startup, then
using QMP to add NIC devices via the `device_add` command, and then
using the `cont` command to start the VM guest.
This is working mostly fine, but there is one issue; the provided
"bootindex" property is not respected.
E.g.
device_add
{"addr":"00.0","bootindex":"0","bus":"qemu_pcie4","driver":"virtio-net-pci","id":"dev-lxd_eth0","mac":"00:16:3e:0c:69:e7","mq":"on","multifunction":"off","netdev":"lxd_eth0","vectors":"6"}
The device is seen within the VM guest and the VM BIOS, but its boot
order is last rather than first.
We've also tried using a non-zero bootindex of 1 and that has the same
effect.
After discussions on #qemu IRC channel, we found that running
`system_reset` after adding the devices allowed the `bootindex` property
to be respected.
So this looks like bug. Perhaps we can discuss it in one of the
forthcoming community calls?
Thanks
Tom Parrott
