Re: [PATCH v2 04/23] mm/balloon_compaction: centralize basic page migration handling

David Hildenbrand (Red Hat)
2026-01-19T22:25:22Z

On 1/19/26 23:22, David Hildenbrand (Red Hat) wrote:
> On 1/15/26 10:19, David Hildenbrand (Red Hat) wrote:
>> Let's update the balloon page references, the balloon page list, the
>> BALLOON_MIGRATE counter and the isolated-pages counter in
>> balloon_page_migrate(), after letting the balloon->migratepage()
>> callback deal with the actual inflation+deflation.
>>
>> Note that we now perform the balloon list modifications outside of any
>> implementation-specific locks: which is fine, there is nothing special
>> about these page actions that the lock would be protecting.
>>
>> The old page is already no longer in the list (isolated) and the new page
>> is not yet in the list.
>>
>> Let's use -ENOENT to communicate the special "inflation of new page
>> failed after already deflating the old page" to balloon_page_migrate() so
>> it can handle it accordingly.
>>
>> While at it, rename balloon->b_dev_info to make it match the other
>> functions. Also, drop the comment above balloon_page_migrate(), which
>> seems unnecessary.
>>
>> Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
>> ---
>
> Andrew, the following on top:

Ah no, I'll rather resend the whole thing, as it creates some conflicts
in the other patches.

--
Cheers

David