Re: [PATCH v8 02/18] liveupdate: luo_core: integrate with KHO
From: Pasha Tatashin
Date: Tue Nov 25 2025 - 14:02:09 EST
On Tue, Nov 25, 2025 at 1:54 PM Mike Rapoport <rppt@xxxxxxxxxx> wrote:
>
> On Tue, Nov 25, 2025 at 11:58:32AM -0500, Pasha Tatashin wrote:
> > Integrate the LUO with the KHO framework to enable passing LUO state
> > across a kexec reboot.
> >
> > This patch implements the lifecycle integration with KHO:
> >
> > 1. Incoming State: During early boot (`early_initcall`), LUO checks if
> > KHO is active. If so, it retrieves the "LUO" subtree, verifies the
> > "luo-v1" compatibility string, and reads the `liveupdate-number` to
> > track the update count.
> >
> > 2. Outgoing State: During late initialization (`late_initcall`), LUO
> > allocates a new FDT for the next kernel, populates it with the basic
> > header (compatible string and incremented update number), and
> > registers it with KHO (`kho_add_subtree`).
> >
> > 3. Finalization: The `liveupdate_reboot()` notifier is updated to invoke
> > `kho_finalize()`. This ensures that all memory segments marked for
> > preservation are properly serialized before the kexec jump.
> >
> > Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
> > Reviewed-by: Pratyush Yadav <pratyush@xxxxxxxxxx>
>
> Reviewed-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
Thank you!
Pasha