Re: [PATCH v2] kho: add support for deferred struct page init

Pratyush Yadav
2026-02-10T14:00:34Z

On Tue, Feb 10 2026, Pratyush Yadav wrote:

> On Tue, Feb 10 2026, Michal Clapinski wrote:
>
>> When `CONFIG_DEFERRED_STRUCT_PAGE_INIT` is enabled, struct page
>> initialization is deferred to parallel kthreads that run later
>> in the boot process.
>>
>> During KHO restoration, `deserialize_bitmap()` writes metadata for
>> each preserved memory region. However, if the struct page has not been
>> initialized, this write targets uninitialized memory, potentially
>> leading to errors like:
>> ```
>> BUG: unable to handle page fault for address: ...
>> ```
>>
>> Fix this by introducing `kho_get_preserved_page()`, which ensures
>> all struct pages in a preserved region are initialized by calling
>> `init_deferred_page()` which is a no-op when deferred init is disabled
>> or when the struct page is already initialized.
>>
>> Signed-off-by: Evangelos Petrongonas <epetron@amazon.de>
>> Signed-off-by: Michal Clapinski <mclapinski@google.com>
>
> Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>

Wait. I just noticed that Michal took authorship of the patch. I talked
to him and he said that was by mistake.

Andrew, can you please give the authorship to Evangelos when you queue
the patch?

--
Regards,
Pratyush Yadav