Re: The future of PageAnonExclusive

David Hildenbrand
2024-12-11T16:15:22Z

On 11.12.24 17:11, Matthew Wilcox wrote:
> On Wed, Dec 11, 2024 at 04:50:12PM +0100, David Hildenbrand wrote:
>> On 11.12.24 16:45, Matthew Wilcox wrote:
>>> [1] https://kernelnewbies.org/MatthewWilcox/Memdescs
>>>
>>> Don't get too excited about "we're almost out of types". The "managed"
>>> type has subtypes. We could also collapse "file" and "anon" into a
>>> single type and distinguish between them with a bit in the folio.
>>>
>>> Anyway, yes, we can do one per-page flag. Two per-page flags starts to
>>> get dicey.
>>
>> hwpoison? :/
>
> type 9! My thinking is that the hwpoison type contains an orig_memdesc
> field, as well as whatever else is needed to describe the hwpoison that
> was discovered (start, length, what else?)

Ah, I see. So you'd have to allocate that type during a MCE, and have
all file/anon detection code respect that indirection as well.