On Wed, May 20, 2020 at 07:23:32PM +0200, Paolo Bonzini wrote: > On 20/05/20 19:13, Stefan Hajnoczi wrote: > > Hi, > > libvirt refuses to set KVM_HINTS_DEDICATED when the CPU model is not > > host-passthrough. > > > > Is there a reason for this limitation? > > > > My understanding is that KVM_HINTS_DEDICATED means the vCPU is pinned to > > a host CPU that is not shared with other tasks. Any KVM vCPU should be > > able to support this feature, regardless of whether host-passthrough is > > used or not. > > Perhaps it's because KVM_HINTS_DEDICATED enables mwait passthrough, and > the details of mwait vary per CPU model? KVM_HINTS_DEDICATED (now known as KVM_HINTS_REALTIME) is also used by cpuidle-haltpoll. In that case we don't care about mwait. CPU passthrough can prevent live migration, so I think we should relax this check, if possible. Wim: Can you let us know what the original intention of checking for cpu-passthrough was? Thanks, Stefan
Attachment:
signature.asc
Description: PGP signature
