> On May 14, 2026, at 01:46, Andrew Morton <[email protected]> wrote:
>
> On Wed, 13 May 2026 21:04:28 +0800 Muchun Song <[email protected]>
> wrote:
>
>> In this series, HVO is redefined as Hugepage Vmemmap Optimization: a
>> general vmemmap optimization model for large hugepage-backed mappings,
>> rather than a HugeTLB-only implementation detail.
>>
>> The existing code grew around the original HugeTLB-specific HVO path,
>> while device DAX developed similar but separate vmemmap optimization
>> handling. As a result, the current implementation carries duplicated
>> logic, boot-time special cases, and subsystem-specific interfaces around
>> what is fundamentally the same sparse-vmemmap optimization.
>>
>> This series generalizes that optimization into a common framework used
>> by both HugeTLB and device DAX.
>>
>> The first few patches include some minor bug fixes found during AI-aided
>> review of the current code. These fixes are not the main goal of the
>> series, but the later refactoring and unification work depends on them,
>> so they are included here as preparatory changes.
>>
>> The series then reworks the relevant early boot and sparse
>> initialization paths, introduces a generic section-based sparse-vmemmap
>> optimization infrastructure, switches HugeTLB and device DAX over to the
>> shared implementation, and removes the old special-case code.
>>
>> ...
>>
>> 46 files changed, 743 insertions(+), 1812 deletions(-)
>
> Gulp.
Sorry for a so big series to refactor lots of things.
>
> I think the first 15ish patches (little fixes and cleanups and
> refactorings) are ready to go in immediately?
Overall, I believe the first 12 patches (excluding the bugfixes)
have already been reviewed by Mike and are theoretically ready
to be merged.
>
> Perhaps you could prepare such things as a separate series. Or tell me
> which ones are suitable and I'll fudge up a [0/N]?
I'd prefer to group the first 19 patches into a single series (titled
"Refactor bootmem gigantic hugepage allocation"). Therefore, I
suggest waiting for feedback from other maintainers/reviewers;
once patches 13-19 pass review, I will send them out as a standalone
series.
Muchun,
Thanks.
