On Thu, Jun 29, 2017 at 10:39:26 +0200, Marek Marczykowski-Górecki wrote: > On Thu, Jun 29, 2017 at 10:04:42AM +0200, Jiri Denemark wrote: > > On Thu, Jun 29, 2017 at 03:11:42 +0200, Marek Marczykowski-Górecki wrote: > > > Set CPU features in appropriate libxl structure. > > > Use old "xend" syntax, because it allow control over any bit and libvirt > > > already have API for translating features to appropriate cpuid bits. And > > > also features naming in libxl do not match the one of libvirt in > > > multiple cases. > > > > How does the new syntax look like? > > "host,tm=0,sse3=0" Is "host" fixed there or are other CPU models supported too? If only "host" is allowed, libxl driver should support host-passthrough mode only and it would be pretty easy to map it to the libxl's syntax. The following CPU XML <cpu mode='host-passthrough'> <feature name='avx' policy='disable'/> <feature name='aes' policy='require'/> </cpu> could be directly translated into "host,avx=0,aes=1". > > And would it be actually better? > > Maybe? But the new syntax use different names for many features (like > pni vs sse3, or sep vs sysenter), so it would require some ugly > translation table... I don't a translation table would be ugly. > What I would really like here, is to get list of bits specified with > <feature ...>, _without_ those defined by <model>. And maybe even > without requiring <model> to be set at all. That's what host-passthrough mode is for. Jirka -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list