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

Pratyush Yadav
2026-02-10T13:55:31Z

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>

[...]

--
Regards,
Pratyush Yadav