Re: [PATCH RFC v2 05/27] mm: page_alloc: Add an arch hook to allow prep_new_page() to fail

From: David Hildenbrand
Date: Fri Nov 24 2023 - 14:35:57 EST


On 19.11.23 17:56, Alexandru Elisei wrote:
Introduce arch_prep_new_page(), which will be used by arm64 to reserve tag
storage for an allocated page. Reserving tag storage can fail, for example,
if the tag storage page has a short pin on it, so allow prep_new_page() ->
arch_prep_new_page() to similarly fail.

But what are the side-effects of this? How does the calling code recover?

E.g., what if we need to populate a page into user space, but that particular page we allocated fails to be prepared? So we inject a signal into that poor process?

--
Cheers,

David / dhildenb