Alex, On 8/19/2019 4:57 AM, Alexander Graf wrote: > > > On 15.08.19 18:25, Suthikulpanit, Suravee wrote: >> Currently, there is no way to tell whether APICv is active >> on a particular VM. This often cause confusion since APICv >> can be deactivated at runtime. >> >> Introduce a debugfs entry to report APICv state of a VM. >> This creates a read-only file: >> >> /sys/kernel/debug/kvm/70860-14/apicv-state >> >> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx> > > Shouldn't this first and foremost be a VM ioctl so that user space can inquire its own state? > > > Alex I introduce this mainly for debugging similar to how KVM is currently provides some per-VCPU information: /sys/kernel/debug/kvm/15957-14/vcpu0/ lapic_timer_advance_ns tsc-offset tsc-scaling-ratio tsc-scaling-ratio-frac-bits I'm not sure if this needs to be VM ioctl at this point. If this information is useful for user-space tool to inquire via ioctl, we can also provide it. Thanks, Suravee