Re: [PATCH] livepatch: support for repatching a function

[Josh Poimboeuf <jpoimboe@redhat.com>]

On Mon, Jan 19, 2015 at 08:48:42PM +0100, Jiri Kosina wrote:
> On Mon, 19 Jan 2015, Josh Poimboeuf wrote:
> 
> > > If this is implemented really in a fully stackable manner (i.e. you 
> > > basically would be able to disable only the function that is currently 
> > > "active", i.e. on top of the stack), woudln't that provide more 
> > > predictable semantics?
> > 
> > Yes, I agree.  Thanks for the comment.
> > 
> > Would you want to enforce stacking even if there are no dependencies
> > between the patches?  I think that would be easiest (and cleanest).
> 
> Yup, I think that makes the most sense (especially in this "first step"). 
> Relaxing the revert rules to cover only patches which are really dependent 
> on each other (and we'd have to be careful about defining the meaning 
> this, especially with repsect to various consistency models coming in the 
> future) is something tha can always be done later on top.

Sounds good.  I'll do a v2.

FYI, I've also been working on a prototype of a consistency model, based
on my discussions with Vojtech on the list a few months ago
(LEAVE_PATCHED_SET + SWITCH_THREAD).  I'll probably have some patches to
send out for comments in a few weeks.  That should hopefully be a good
starting point for more discussion about the consistency model(s).

-- 
Josh