Re: [RFC PATCH v1.9 00/14] livepatch: hybrid consistency model

From: Miroslav Benes
Date: Tue Apr 05 2016 - 10:24:40 EST


On Mon, 4 Apr 2016, Josh Poimboeuf wrote:

> > I'd add a fake signal facility for sleeping non-migrated tasks. This
> > would accelerate a migration to a new universe. We have it in kgraft for
> > quite some time and it worked out great. See
> > lkml.kernel.org/r/1430739625-4658-9-git-send-email-jslaby@xxxxxxx which
> > went with Jiri's kgraft-on-klp patch set. See also Oleg's reply as it is
> > important (I changed kgraft implementation according to that).
>
> Ok, I'll look into sending a fake signal to remaining tasks.

Oh, do not worry about this one. I can prepare a patch once we discuss and
review the rest. I think you have a lot on your plate even now.

There are several options how to do it. I think it would be nice not send
a fake signal immediately. So we can...

1. do it after some time of waiting, or

2. we can have a knob in sysfs for an admin to send a fake signal if he
does not want to wait anymore, or

3. (and this is crazy one) we can trace the progress of a migration and
when there is none for several iterations we can send a signal

...

Miroslav