[CRIU] [PATCH 2/2] cpu: Add 'ins' mode to --cpu-cap option

[Pavel Emelyanov]

On 12/17/2014 04:48 PM, Cyrill Gorcunov wrote:
> 
> In this mode we test if target cpu has all features present
> in image file but do not require bit to bit match: target cpu
> may be a new one with more features present.
> 
> Signed-off-by: Cyrill Gorcunov <gorcunov at openvz.org>
> ---
>  Documentation/criu.txt |   6 +++
>  arch/x86/cpu.c         | 122 +++++++++++++++++++++++++++++++++++++++++++++++--
>  cr-dump.c              |   2 +-
>  cr-restore.c           |   2 +-
>  crtools.c              |   4 +-
>  include/cr_options.h   |   3 +-
>  6 files changed, 130 insertions(+), 9 deletions(-)

I've tried to compare all the possible --cpu-cap options we might
have an failed.

Let's summarize, CPU has many features. Here's what we get when we
specify --cpu-cap $smth option.

all -- need all caps... Hm, OK

cpu -- all caps should _match_.

fpu -- only FPU subset of features should be equal or "better". The
       rest isn't checked.

ins -- only "instructions" should be equal or "better". The rest
       isn't checked.

Is that correct?
What's the difference between "all" and "cpu"?
Does "ins" include "fpu"?
Can we request for "all caps should be equal or better"?

Thanks,
Pavel