Hi Salil,
I've pushed the branch here: https://gitlab.arm.com/linux-arm/linux-jm/-/commits/virtual_cpu_hotplug/rfc/...
I've not tested the qemu TCG workarounds .. but I figure I'm the only one that cares about those! I've not done any testing on x86 for this - I plan to do that before posting.
Thanks,
James