Masking CPU Flags Via Libvirt Xml Not Working?
Hi,
Has anyone here managed to get cpu masking working via libvirt?
Intention to enable VM migrations between hosts of a different CPU
generation.
Inside my xml I’m providing the model as well as a list of features to specifically disable, but none of it seems to take any effect. On booting the VM I still see the disabled flags in /proc/cpuinfo
Doing a dumpxml against the domU once it’s booted leaves out the entire
Anyone have this working or able to offer some suggestions?
Thanks!
– Nathan
2 thoughts on - Masking CPU Flags Via Libvirt Xml Not Working?
To add to this, I’ve tried using the boot options to set the cpu mask instead:
xen_commandline : dom0_mem 48M,max:2048M loglvl=all guest_loglvl=all cpuid_mask_ecx=0x009ee3fd cpuid_mask_edx=0xbfebfbff
Unfortunately still no luck. There’s no errors in xm dmesg to indicate the settings were / weren’t applied, it simply doesn’t seem to do anything.
– Nathan
Hi,
I guess this is the wrong approach:
Libvirt does manage cpu type in an xml file, you would have to alter this xml file:
/usr/share/libvirt/cpu_map.xml
HTH
PS: Maybe add an feature request upstream to enable this for all libvirt users?
I have seen this request quite some time on different mailing lists.
Am 27.08.2014 20:08, schrieb Nathan March: