Re: [PATCH 1/1] mm/hugetlb: do not dissolve gigantic pages without runtime support

From: Muchun Song

Date: Fri Aug 21 2026 - 05:40:46 EST




> On Aug 21, 2026, at 01:33, David Hildenbrand (Arm) <david@xxxxxxxxxx> wrote:
>
> On 8/20/26 11:38, Muchun Song wrote:
>>
>>
>>> On Aug 19, 2026, at 16:52, David Hildenbrand (Arm) <david@xxxxxxxxxx> wrote:
>>>
>>> On 8/17/26 18:20, Longlong Xia wrote:
>>>> From: Longlong Xia <xialonglong@xxxxxxxxxx>
>>>>
>>>> dissolve_free_hugetlb_folio() doesn't check hstate_is_gigantic_no_runtime(h)
>>>> though remove_hugetlb_folio()/update_and_free_hugetlb_folio() silently
>>>> bail for such folios
>>>
>>> That's odd. Why do they silently skip such folios instead of warning that
>>> something unexpected is happening?
>>>
>>> This screams for a cleanup unless I am missing something :)
>>
>> Hi David,
>>
>> Sashiko actually has a pretty detailed description [1]. So I think it deserves a fix.
>
> That's not what I meant. I agree that its a valid fix, but I think the code
> should possibly be reworked to not get silent rejection from these
> functions--IOW, likely the callers should make sure to never call them in this
> scenario, and then VM_WARN_ON() instead of handling it silently.

OK. Make sense.

Muchun,
Thanks.

>
>
> --
> Cheers,
>
> David