This doesn't actually wait for the target vcpu thread to bounce back to userspace, do we need to synchronize? Is it expected that the target vcpu is usually the current vcpu?

CPU_OFF can only be called from the target CPU

In D51768#1183065, @andrew wrote:

CPU_OFF can only be called from the target CPU

If we expect the kernel to guarantee that, it'd be nice to assert it here.

This revision is now accepted and ready to land.Thu, Aug 7, 12:46 PM

I'm not sure there is anything to assert on. CPU_OFF is defined to "Power down the calling core" & doesn't take any arguments.

In D51768#1183137, @andrew wrote:

I'm not sure there is anything to assert on. CPU_OFF is defined to "Power down the calling core" & doesn't take any arguments.

Ah ok, I thought the target vCPU was a parameter to the CPU_OFF command.

Closed by commit rG642c0334f50a: bhyve/arm64: Implement PSCI_FNID_CPU_OFF (authored by andrew). · Explain WhyThu, Aug 7, 4:43 PM

This revision was automatically updated to reflect the committed changes.

andrew added a commit: rG642c0334f50a: bhyve/arm64: Implement PSCI_FNID_CPU_OFF.