On Fri, 19 Jul 2019, Petr Mladek wrote: > Documentation explaining the motivation, capabilities, and usage > of the new API for tracking system state changes. > > Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> > --- > Documentation/livepatch/index.rst | 1 + > Documentation/livepatch/system-state.rst | 167 +++++++++++++++++++++++++++++++ > 2 files changed, 168 insertions(+) > create mode 100644 Documentation/livepatch/system-state.rst > > diff --git a/Documentation/livepatch/index.rst b/Documentation/livepatch/index.rst > index edd291d51847..94bbbc2c8993 100644 > --- a/Documentation/livepatch/index.rst > +++ b/Documentation/livepatch/index.rst > @@ -9,6 +9,7 @@ Kernel Livepatching > > livepatch > callbacks > + system-state > cumulative-patches > module-elf-format > shadow-vars This is really a nitpick, but wouldn't it be better to move system-state to the end of the list, because it relies on the information from the other parts? > diff --git a/Documentation/livepatch/system-state.rst b/Documentation/livepatch/system-state.rst > new file mode 100644 > index 000000000000..f04ef2b9089a > --- /dev/null > +++ b/Documentation/livepatch/system-state.rst > @@ -0,0 +1,167 @@ > +==================== > +System State Changes > +==================== > + > +Some users are really reluctant to reboot a system. This brings the need > +to provide more livepatches and maintain some compatibility between them. > + > +Maintaining more livepatches is much easier with cumulative livepatches. > +Each new livepatch completely replaces any older one. It can keep, > +add, and even remove fixes. And it is typically safe to replace any version > +of the livepatch with any other one thanks to the atomic replace feature. > + > +The problems might come with shadow variables and callbacks. They might > +change the system behavior or state so that it is not longer safe to s/not longer/no longer/ (there are more instances of this in the patch). Miroslav
