lkml.org 
[lkml]   [2018]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled
On Thu, 20 Dec 2018, Joao Moreira wrote:

> On 12/20/18 12:33 AM, Miroslav Benes wrote:
> > On Wed, 19 Dec 2018, Jiri Kosina wrote:
> >
> >> On Wed, 19 Dec 2018, Josh Poimboeuf wrote:
> >>
> >>> Also the commit message needs an analysis of the performance impacts.
> >>
> >> Agreed. Especially as it's expected (*) to be completely in the noise
> >> particularly for the kernel, it'd be good to have that documented in the
> >> changelog.
> >>
> >> (*) actually measured already for some subset of the IPA optimizations
> >
> > Ok, we can do that. I don't expect the results to be different from the
> > last measurement as Jiri mentions. The sets of disabled optimizations are
> > similar.
> >
> > I'll add it to v2.
> >
> > On Wed, 19 Dec 2018, Jiri Kosina wrote:
> >
> >> On Wed, 19 Dec 2018, Josh Poimboeuf wrote:
> >>
> >>>>> This option only makes sense for source-based patch generation, so isn't
> >>>>> it a bit premature to make this change without proper source-based patch
> >>>>> tooling?
> >>>>
> >>>> The reality is though that before the full-fledged patch tooling exists,
> >>>> people are actually already writing livepatches by hand, so this option
> >>>> is
> >>>> useful for them.
> >>>
> >>> Fair enough.
> >
> > Yes, that was the reason I sent it. It would not make sense to wait for
> > the tooling in this case, because -flive-patching is useful even now,
> > since there is a way to prepare livepatches without any tooling.
> >
> >>> Though, upstream, almost everybody seems to use kpatch-build, for which
> >>> this patch doesn't help. And people will continue to do so until we
> >>> have decent source-based tooling. Will the klp-convert patches be
> >>> revived soon?
> >>
> >> Let me add Joao, who's working on that.
> >>
> >> Joao, I think you had something basically ready for upstream exposure,
> >> right?
> >
> > I think that when Joao posted it a long time ago, the conclusion was that
> > it would be better to wait for the source-based tooling and have the
> > complete solution. I may misremember though.
>
> Your memories match mine, Miroslav.
>
> FTR, we recently integrated klp-convert to SLE. There were some fixes in
> comparison with the version which was submitted upstream, thus a v2 of the
> patches is necessary.
>
> >
> > If Josh thinks that it would be acceptable to have klp-convert merged even
> > without the tooling, I'm all for it.
> >
> Of course I can work on that and I'll be glad to do so / submit this new
> version, if this is now something considered useful.

Yes, please.

Some context first. We decided to remove the integration into kbuild at
SUSE. klp-convert is called from rpm .spec file directly after a livepatch
module is compiled.

I think we should preserve kbuild process in upstream though. It makes
more sense there.

Miroslav

\
 
 \ /
  Last update: 2018-12-21 10:49    [W:0.074 / U:3.912 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site