> > > Yes, but _why_? I know _what_ a debugs knob allows, but you have yet to explain > > > why this > > I think that if such an interface is provided, it can be used to check the source of > > vm's max_halt_poll_ns, general module parameter or per-vm configuration. > > When configured through per-vm, such an interface can be used to monitor this > > configuration. If there is an error in the setting through KVMCAP_HALL_POLL, such > > an interface can be used to fix or reset it dynamicly. > But again, that argument can be made for myriad settings in KVM. And unlike many > settings, a "bad" max_halt_poll_ns can be fixed simply by redoing KVM_CAP_HALL_POLL. Yes, Whether it is convenient to redo it will depend on the userspace. > It's not KVM's responsibility to police userspace for bugs/errors, and IMO a > backdoor into max_halt_poll_ns isn't justified. Yes, It's not KVM's responsibility to police userspace. In addition to depend on userspace redo, it can be seen as a planB to ensure that the VM works as expected.
