[pve-devel] qemu2.7: cpu hotplug && hot-unplug v1

Alexandre Derumier aderumier at odiso.com
Tue Sep 6 12:41:52 CEST 2016

This patch series implement new qemu 2.7 cpu hotplug framework, with device_add|device_del

hot-unplug is working now !

config example:
cpu: kvm64

generate cmdline
-cpu kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,enforce
-smp 1,sockets=2,cores=2,maxcpus=4
-device kvm64-x86_64-cpu,id=cpu2,socket-id=0,core-id=1,thread-id=0 
-device kvm64-x86_64-cpu,id=cpu3,socket-id=1,core-id=0,thread-id=0 
-device kvm64-x86_64-cpu,id=cpu4,socket-id=1,core-id=1,thread-id=0 

First core is not hotpluggable (-smp 1). (socket-id=0,core-id=0)
Others cores are added with -device, with cpumodel,socket-id && core-id.

cpuflags are defined globally in -cpu , and are auto applied on hotplug

Tested with debian jessie, kernel 3.16.

This new config is only apply with machine 2.7+cpu hotplug enabled, as it break live migration.

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