Re: prctl(PR_SET_MM)

[u3557@miso.sublimeip.com (Amnon Shiloh)]

Hi Cyrill,

Cyrill Gorcunov wrote:

> On Tue, Feb 19, 2013 at 05:25:31PM +1100, Amnon Shiloh wrote:
> > 
> > To reconstruct Linux process(es), one must be able to restore all their
> > memory contents, states and registers to their original and consistent
> > values.
> 
> I personally don't mind if this come become y by default, because it will
> work for us.

I don't mind either, to say the least, to have CONFIG_CHECKPOINT_RESTORE
have a "default y" in "init/Kconfig" - that would solve my problem and make
me happy, as well as your group and others, but we are told here that Linus
has a policy vetoing such changes and I don't believe either of us can make
him change his mind.

As such, we must look at other options, such as having the code in
"kernel/sys.c" out in the open, not enclosed by any #ifdef's altogether
- surely you would like that!

> Still I guess if you need to reconstruct Linux process(es)
> plain prctl extension is not enough, you still need a functionality which
> is enclosed in config-checkpoint-restore (say /proc/pid/map_files, kcmp),
> no?

My process-migration package only reconstructs Linux processes partially:
as it's a bit different than any classical checkpoint-restore, the critical
code in "kernel/sys.c" is all I need at the moment (from within
CONFIG_CHECKPOINT_RESTORE).  I do appreciate that anyone attempting to
perform complete, classical, checkpoint-restore operations, needs more
than that.

Best Regards,
Amnon.