Re: powerpc/e500: WARNING: at mm/hugetlb.c:4755 hugetlb_add_hstate

["David Hildenbrand (Red Hat)" <david@kernel.org>]

On 07.11.25 09:00, Sourabh Jain wrote:
> 
> 
> On 06/11/25 20:32, David Hildenbrand (Red Hat) wrote:
>>>> Yes, we discussed that in [1].
>>>>
>>>> We'll have to set ARCH_HAS_GIGANTIC_PAGE on ppc and increase
>>>> MAX_FOLIO_ORDER, because apparently, there might be ppc configs that
>>>> have even larger hugetlb sizes than PUDs.
>>>>
>>>> @Cristophe, I was under the impression that you would send a fix. Do
>>>> you
>>>> want me to prepare something and send it out?
>>>
>>> Indeed I would have liked to better understand the implications of all
>>> this, but I didn't have the time.
>>
>> Indeed, too me longer than it should to understand and make up my mind
>> as well.
>>
>>>
>>> By the way, you would describe the fix better than me so yes if you can
>>> prepare and send a fix please do.
>>
>> I just crafted the following. I yet have to test it more, some early
>> feedback+testing would be appreciated!
>>
>>  From 274928854644c49c92515f8675c090dba15a0db6 Mon Sep 17 00:00:00 2001
>> From: "David Hildenbrand (Red Hat)" <david@kernel.org>
>> Date: Thu, 6 Nov 2025 11:31:45 +0100
>> Subject: [PATCH] mm: fix MAX_FOLIO_ORDER on some ppc64 configs with
>> hugetlb
> 
> b4 did not detect this patch, and manually copying the patch text from this
> reply also did not apply cleanly on upstream master and linuxppc
> master/next.

I have it on a branch here:

https://github.com/davidhildenbrand/linux/commit/274928854644c49c92515f8675c090dba15a0db6

https://github.com/davidhildenbrand/linux.git max_folio_order

-- 
Cheers

David