Re: [PATCH 1/1] userfaultfd: remove WRITE_ONCE when setting folio->index during UFFDIO_MOVE

From: Peter Xu
Date: Mon Apr 15 2024 - 09:39:10 EST


On Sun, Apr 14, 2024 at 07:08:21PM -0700, Suren Baghdasaryan wrote:
> When folio is moved with UFFDIO_MOVE it gets locked before the rmap and
> index are modified. Due to the folio lock being already held, WRITE_ONCE()
> is not needed when setting the folio index. Remove it.
>
> Reported-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: Peter Xu <peterx@xxxxxxxxxx>
> Cc: Lokesh Gidra <lokeshgidra@xxxxxxxxxx>

Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>

--
Peter Xu