Re: [PATCH v3] mm/page_alloc: clear page->private in free_pages_prepare()

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

On 2/9/26 18:44, Zi Yan wrote:
> On 9 Feb 2026, at 12:36, David Hildenbrand (Arm) wrote:
> 
>> On 2/9/26 17:33, Zi Yan wrote:
>>>
>>>
>>> I agree. Silently fixing non zero ->private just moves the work/responsibility
>>> from users to core mm. They could do better. :)
>>>
>>> We can have a patch or multiple patches to fix users do not zero ->private
>>> when freeing a page and add the patch below.
>>
>> Do we know roughly which ones don't zero it out?
> 
> So far based on [1], I found:
> 
> 1. shmem_swapin_folio() in mm/shmem.c does not zero ->swap.val (overlapping
> with private);
> 2. __free_slab() in mm/slub.c does not zero ->inuse, ->objects, ->frozen
> (overlapping with private).
> 
> Mikhail found ttm_pool_unmap_and_free() in drivers/gpu/drm/ttm/ttm_pool.c
> does not zero ->private, which stores page order.
>

Looks doable then :) Should we take v3 as a quick fix to backport then?

-- 
Cheers,

David