lkml.org 
[lkml]   [2018]   [Dec]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v14 05/11] livepatch: Simplify API by removing registration step
On Tue, 4 Dec 2018, Petr Mladek wrote:

> On Tue 2018-12-04 13:54:55, Miroslav Benes wrote:
> > > diff --git a/Documentation/livepatch/livepatch.txt b/Documentation/livepatch/livepatch.txt
> > > index 2d7ed09dbd59..d849af312576 100644
> > > --- a/Documentation/livepatch/livepatch.txt
> > > +++ b/Documentation/livepatch/livepatch.txt
> > > @@ -12,12 +12,11 @@ Table of Contents:
> > > 4. Livepatch module
> > > 4.1. New functions
> > > 4.2. Metadata
> > > - 4.3. Livepatch module handling
> > > 5. Livepatch life-cycle
> > > - 5.1. Registration
> > > + 5.1. Loading
> > > 5.2. Enabling
> > > 5.3. Disabling
> > > - 5.4. Unregistration
> > > + 5.4. Removing
> > > 6. Sysfs
> > > 7. Limitations
> > >
> > > @@ -298,117 +297,91 @@ into three levels:
> > > see the "Consistency model" section.
> > >
> > >
> > > -4.3. Livepatch module handling
> > > -------------------------------
> > > -
> > > -The usual behavior is that the new functions will get used when
> > > -the livepatch module is loaded. For this, the module init() function
> > > -has to register the patch (struct klp_patch) and enable it. See the
> > > -section "Livepatch life-cycle" below for more details about these
> > > -two operations.
> > > -
> > > -Module removal is only safe when there are no users of the underlying
> > > -functions. This is the reason why the force feature permanently disables
> > > -the removal. The forced tasks entered the functions but we cannot say
> > > -that they returned back. Therefore it cannot be decided when the
> > > -livepatch module can be safely removed. When the system is successfully
> > > -transitioned to a new patch state (patched/unpatched) without being
> > > -forced it is guaranteed that no task sleeps or runs in the old code.
> >
> > Is the change necessary? The documentation in v13 looked ok and I am not
> > sure if it is better now. Only my opinion though and I understand why you
> > changed it.
>
> The huge rewrite was triggered by an innocent Josh's comment, see
> https://lkml.kernel.org/r/20181017190657.dv3kwx467brzhdnz@treble
>
> I made a big effort to rework the text. I wanted to explain the
> difference between the module loading/unloading and the livepatch
> enabling/disabling in a better structured and hopefully easier to
> understand way.
>
> It is possible that I failed. But let's put it the following way.
> I refuse to do any other big rework of the documentation in this
> patchset. If anyone has a better idea, please provide alternative
> text or a patch.

I let the others to judge if you failed or not, but I guess no one asked
for the huge rewrite. I'm not asking for another one now. I only noticed a
few things and I mentioned them.

Regards,
Miroslav

\
 
 \ /
  Last update: 2018-12-04 16:32    [W:0.055 / U:1.760 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site