Let's compare behavior:
0. Status quo do nothing and succeed
1. Your patch fail with GenericError
2. Your patch less error_setg() do nothing and succeed
3. Immediate removal fail with CommandNotFound
Does the difference between 1. and 3. matter at all? Or is it just
deprecation cargo cult?
Good point. If both the deprecation message and the removal will
result in error for the user ....
Here's my take on it. I'd prefer 3. Immediate removal. I'd also be
fine with 2. Your patch less error_setg(), followed by removal after the
customary deprecation period. 1. plus later removal just doesn't make
sense to me, but it's really no big deal, so if you guys want it...
It all goes down to whether we consider qmp_cpu, a QMP command that does
nothing since its creation and apparently no one ever used it, a
feature. If it's a
feature, then I vote for (2) and removal after 2 releases following the
regular
deprecation policy.
If we consider that applying the policy to qmp_cpu is more trouble than
it's worth,
I'll gladly resend this patch removing it entirely and rewording the
qemu-doc.texi
entry to mention that it was removed because it did nothing and it was of
no use for anyone.