From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Miroslav Benes <mbenes@suse.cz>
Cc: Joe Lawrence <joe.lawrence@redhat.com>,
Petr Mladek <pmladek@suse.com>,
jikos@kernel.org, linux-kernel@vger.kernel.org,
live-patching@vger.kernel.org
Subject: Re: [RFC PATCH 2/2] livepatch: Clear relocation targets on a module removal
Date: Wed, 4 Sep 2019 21:32:02 -0500 [thread overview]
Message-ID: <20190905023202.ed7fecc22xze4pwj@treble> (raw)
In-Reply-To: <alpine.LSU.2.21.1909031447140.3872@pobox.suse.cz>
On Tue, Sep 03, 2019 at 03:02:34PM +0200, Miroslav Benes wrote:
> On Mon, 2 Sep 2019, Joe Lawrence wrote:
>
> > On 9/2/19 12:13 PM, Miroslav Benes wrote:
> > >> I can easily foresee more problems like those in the future. Going
> > >> forward we have to always keep track of which special sections are
> > >> needed for which architectures. Those special sections can change over
> > >> time, or can simply be overlooked for a given architecture. It's
> > >> fragile.
> > >
> > > Indeed. It bothers me a lot. Even x86 "port" is not feature complete in
> > > this regard (jump labels, alternatives,...) and who knows what lurks in
> > > the corners of the other architectures we support.
> > >
> > > So it is in itself reason enough to do something about late module
> > > patching.
> > >
> >
> > Hi Miroslav,
> >
> > I was tinkering with the "blue-sky" ideas that I mentioned to Josh the other
> > day.
>
> > I dunno if you had a chance to look at what removing that code looks
> > like, but I can continue to flesh out that idea if it looks interesting:
>
> Unfortunately no and I don't think I'll come up with something useful
> before LPC, so anything is really welcome.
>
> >
> > https://github.com/joe-lawrence/linux/tree/blue-sky
I like this a lot.
> > A full demo would require packaging up replacement .ko's with a livepatch, as
> > well as "blacklisting" those deprecated .kos, etc. But that's all I had time
> > to cook up last week before our holiday weekend here.
>
> Frankly, I'm not sure about this approach. I'm kind of torn. The current
> solution is far from ideal, but I'm not excited about the other options
> either. It seems like the choice is basically between "general but
> technically complicated fragile solution with nontrivial maintenance
> burden", or "something safer and maybe cleaner, but limiting for
> users/distros". Of course it depends on whether the limitation is even
> real and how big it is. Unfortunately we cannot quantify it much and that
> is probably why our opinions (in the email thread) differ.
How would this option be "limiting for users/distros"? If the packaging
part of the solution is done correctly then I don't see how it would be
limiting.
--
Josh
next prev parent reply other threads:[~2019-09-05 2:32 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-19 12:28 [RFC PATCH 0/2] livepatch: Clear relocation targets on a module removal Miroslav Benes
2019-07-19 12:28 ` [PATCH 1/2] livepatch: Nullify obj->mod in klp_module_coming()'s error path Miroslav Benes
2019-07-28 19:45 ` Josh Poimboeuf
2019-08-19 11:26 ` Petr Mladek
2019-07-19 12:28 ` [RFC PATCH 2/2] livepatch: Clear relocation targets on a module removal Miroslav Benes
2019-07-22 9:33 ` Petr Mladek
2019-08-14 12:33 ` Miroslav Benes
2019-07-28 20:04 ` Josh Poimboeuf
2019-08-14 11:06 ` Miroslav Benes
2019-08-14 15:12 ` Josh Poimboeuf
2019-08-16 9:46 ` Petr Mladek
2019-08-22 22:36 ` Josh Poimboeuf
2019-08-23 8:13 ` Petr Mladek
2019-08-26 14:54 ` Josh Poimboeuf
2019-08-27 15:05 ` Joe Lawrence
2019-08-27 15:37 ` Josh Poimboeuf
2019-09-02 16:13 ` Miroslav Benes
2019-09-02 17:05 ` Joe Lawrence
2019-09-03 13:02 ` Miroslav Benes
2019-09-04 8:49 ` Petr Mladek
2019-09-04 16:26 ` Joe Lawrence
2019-09-05 2:50 ` Josh Poimboeuf
2019-09-05 11:09 ` Petr Mladek
2019-09-05 11:19 ` Jiri Kosina
2019-09-05 13:23 ` Josh Poimboeuf
2019-09-05 13:31 ` Jiri Kosina
2019-09-05 13:42 ` Josh Poimboeuf
2019-09-05 11:39 ` Joe Lawrence
2019-09-05 13:08 ` Josh Poimboeuf
2019-09-05 13:15 ` Josh Poimboeuf
2019-09-05 13:52 ` Petr Mladek
2019-09-05 14:28 ` Josh Poimboeuf
2019-09-05 12:03 ` Miroslav Benes
2019-09-05 12:35 ` Josh Poimboeuf
2019-09-05 12:49 ` Miroslav Benes
2019-09-05 11:52 ` Miroslav Benes
2019-09-05 2:32 ` Josh Poimboeuf [this message]
2019-09-05 12:16 ` Miroslav Benes
2019-09-05 12:54 ` Josh Poimboeuf
2019-09-06 12:51 ` Miroslav Benes
2019-09-06 15:38 ` Joe Lawrence
2019-09-06 16:45 ` Josh Poimboeuf
2019-08-26 13:44 ` Nicolai Stange
2019-08-26 15:02 ` Josh Poimboeuf
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