Re: [PATCH v4 00/14] kexec: introduce Kexec HandOver (KHO)

[Baoquan He]

On 02/06/25 at 08:28pm, Pasha Tatashin wrote:
> On Thu, Feb 6, 2025 at 7:29 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Thu,  6 Feb 2025 15:27:40 +0200 Mike Rapoport <rppt@xxxxxxxxxx> wrote:
> >
> > > This a next version of Alex's "kexec: Allow preservation of ftrace buffers"
> > > series (https://lore.kernel.org/all/20240117144704.602-1-graf@xxxxxxxxxx),
> > > just to make things simpler instead of ftrace we decided to preserve
> > > "reserve_mem" regions.
> > >
> > > The patches are also available in git:
> > > https://git.kernel.org/rppt/h/kho/v4
> > >
> > >
> > > Kexec today considers itself purely a boot loader: When we enter the new
> > > kernel, any state the previous kernel left behind is irrelevant and the
> > > new kernel reinitializes the system.
> >
> > I tossed this into mm.git for some testing and exposure.
> >
> > What merge path are you anticipating?
> >
> > Review activity seems pretty thin thus far?
> 
> KHO is going to be discussed at the upcoming lsfmm, we are also
> planning to send v5 of this patch series (discussed with Mike
> Rapoport) in a couple of weeks. It will include enhancements needed
> for the hypervisor live update scenario:

So is this V4 still a RFC if v5 will be sent by plan? Should we hold the
reviewing until v5? Or this series is a infrustructure building, v5 will
add more details as you listed as below. I am a little confused.

> 
> 1. Allow nodes to be added to the KHO tree at any time
> 2. Remove "activate" (I will also send a live update framework that
> provides the activate functionality).
> 3. Allow serialization during shutdown.
> 4. Decouple KHO from kexec_file_load(), as kexec_file_load() should
> not be used during live update blackout time.
> 5. Enable multithreaded serialization by using hash-table as an
> intermediate step before conversion to FDT.