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

[Zi Yan <ziy@nvidia.com>]

On 22 Oct 2025, at 16:47, Zi Yan wrote:

> 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

this patch is Patch 1.

> 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


--
Best Regards,
Yan, Zi