Re: livepatch/module: remove livepatch module notifier

From: Jessica Yu
Date: Tue Feb 16 2016 - 14:52:07 EST


+++ Miroslav Benes [16/02/16 09:41 +0100]:
On Mon, 15 Feb 2016, Jessica Yu wrote:

+++ Jiri Kosina [16/02/16 00:42 +0100]:
> On Mon, 15 Feb 2016, Josh Poimboeuf wrote:
>
> > So I think the commit causing the regression is 5156dca34a3e, which
> > occurred in the 4.5 cycle, *not* in 4.4.
>
> Agreed, by "4.4 regresion" I mean "regression compared to 4.4"; i.e.
> regression that will become real issue once 4.5 is released.
>
> > Also it's my understanding that only the third patch ("remove ftrace
> > module notifier") is needed to fix the regression, and the other patches
> > are just general improvements. So if needed I think we can just rebase
> > that patch (which already has Rusty's ack I believe) and send it to
> > Linus now.
>
> 3/4 and 4/4 are be sufficient, yes (although I'd like to have this
> confimed by Jessica, as she apparently already has a reliable testcase).

Yes, so Josh is right; technically only patch 3/4 "ftrace/module:
remove ftrace module notifier" is sufficient enough to fix the bug,
and patch 4/4 is just a natural extension of that change. Since I'm
going to be sending out another patchset anyway without the module.c
cleanups, I'll just keep them together.

Yes, 3/4 should be sufficient to fix the bug. However if you take 4/4 too,
you need 1/4 as well. Otherwise we would introduce a bug in error handling
as Petr pointed out.


Hm. I am just realizing that patch 4/4 will still need new ACK's for
the error handling portion. What I'll do is, after testing, send out
patch 3/4 ("ftrace/module: remove ftrace module notifier") as a
standalone patch to be merged immediately, since it fixes an actual
bug. The rest of this patchset will follow separately and can be
reviewed at its own pace.

Jessica