Re: [PATCH v3 0/4] Optimize folio split in memory failure

[Zi Yan <ziy@nvidia.com>]

On 21 Oct 2025, at 23:35, Zi Yan wrote:

> Hi all,
>
> This patchset is a follow-up of "[PATCH v3] mm/huge_memory: do not change
> split_huge_page*() target order silently."[1]. It improves how memory
> failure code handles large block size(LBS) folios with
> min_order_for_split() > 0. By splitting a large folio containing HW
> poisoned pages to min_order_for_split(), the after-split folios without
> HW poisoned pages could be freed for reuse. To achieve this, folio split
> code needs to set has_hwpoisoned on after-split folios containing HW
> poisoned pages.
>
> This patchset includes:
> 1. A patch sets has_hwpoisoned on the right after-split folios after
>    scanning all pages in the folios,

Based on the discussion with David[1], this patch will be sent separately
as a hotfix. The remaining patches will be sent out after Patch 1 is picked
up. Please note that I will address David's feedback in the new version of
Patch 1. Sorry for the inconvenience.

[1] https://lore.kernel.org/all/d3d05898-5530-4990-9d61-8268bd483765@redhat.com/

> 2. A patch adds split_huge_page_to_order(),
> 3. Patch 2 and Patch 3 of "[PATCH v2 0/3] Do not change split folio target
>    order"[2],
>
> This patchset is based on mm-new.
>
> Changelog
> ===
> From V2[2]:
> 1. Patch 1 is sent separately as a hotfix[1].
> 2. set has_hwpoisoned on after-split folios if any contains HW poisoned
>    pages.
> 3. added split_huge_page_to_order().
> 4. added a missing newline after variable decalaration.
> 5. added /* release= */ to try_to_split_thp_page().
> 6. restructured try_to_split_thp_page() in memory_failure().
> 7. fixed a typo.
> 8. clarified the comment in soft_offline_in_use_page().
>
>
> Link: https://lore.kernel.org/all/20251017013630.139907-1-ziy@nvidia.com/ [1]
> Link: https://lore.kernel.org/all/20251016033452.125479-1-ziy@nvidia.com/ [2]
>
> Zi Yan (4):
>   mm/huge_memory: preserve PG_has_hwpoisoned if a folio is split to >0
>     order
>   mm/huge_memory: add split_huge_page_to_order()
>   mm/memory-failure: improve large block size folio handling.
>   mm/huge_memory: fix kernel-doc comments for folio_split() and related.
>
>  include/linux/huge_mm.h | 22 ++++++++++++-----
>  mm/huge_memory.c        | 55 ++++++++++++++++++++++++++++++-----------
>  mm/memory-failure.c     | 30 +++++++++++++++++++---
>  3 files changed, 82 insertions(+), 25 deletions(-)
>
> -- 
> 2.51.0


--
Best Regards,
Yan, Zi