Re: [PATCH RFC] mm: Fix kernel BUG when userfaultfd_move encounters swapcache

[Peter Xu]

On Thu, Feb 20, 2025 at 10:21:01PM +1300, Barry Song wrote:
> 2. src_anon_vma and its lock – swapcache doesn’t require it（folio is not mapped）

Could you help explain what guarantees the rmap walk not happen on a
swapcache page?

I'm not familiar with this path, though at least I see damon can start a
rmap walk on PageAnon almost with no locking..  some explanations would be
appreciated.

-- 
Peter Xu