On Sat, 11 Nov 2017, Dan Williams wrote:
> Currently only get_user_pages_fast() can safely handle the writable gup
> case due to its use of pud_access_permitted() to check whether the pud
> entry is writable. In the gup slow path pud_write() is used instead of
> pud_access_permitted() and to
Currently only get_user_pages_fast() can safely handle the writable gup
case due to its use of pud_access_permitted() to check whether the pud
entry is writable. In the gup slow path pud_write() is used instead of
pud_access_permitted() and to date it has been unimplemented, just calls
BUG_ON().
