Re: [PATCH v7 02/22] liveupdate: luo_core: integrate with KHO
From: Pratyush Yadav
Date: Mon Nov 24 2025 - 09:21:44 EST
On Sat, Nov 22 2025, 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.
>
> LUO now depends on `CONFIG_KEXEC_HANDOVER`.
Nit: This patch does not add the dependency. That is done by patch 1. I
guess that change needs to be moved here or the comment removed?
Other than this,
Reviewed-by: Pratyush Yadav <pratyush@xxxxxxxxxx>
[...]
--
Regards,
Pratyush Yadav