On Fri, 18 May 2018 18:35:08 -0700 Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > get_user_pages_fast() for device pages is missing the typical validation > that all page references have been taken while the mapping was valid. > Without this validation truncate operations can not reliably coordinate > against new page reference events like O_DIRECT. > > Cc: <stable@xxxxxxxxxxxxxxx> I'm not seeing anything in the changelog which justifies a -stable backport. ie: a description of the end-user-visible effects of the bug?