Re: [PATCH 02/12] mm: Convert pXd_devmap checks to vma_is_dax

Jason Gunthorpe
2025-06-03T13:35:11Z

On Thu, May 29, 2025 at 04:32:03PM +1000, Alistair Popple wrote:
> Currently dax is the only user of pmd and pud mapped ZONE_DEVICE
> pages. Therefore page walkers that want to exclude DAX pages can check
> pmd_devmap or pud_devmap. However soon dax will no longer set PFN_DEV,
> meaning dax pages are mapped as normal pages.
>
> Ensure page walkers that currently use pXd_devmap to skip DAX pages
> continue to do so by adding explicit checks of the VMA instead.
>
> Signed-off-by: Alistair Popple <apopple@nvidia.com>
> ---
> fs/userfaultfd.c | 2 +-
> mm/hmm.c | 2 +-
> mm/userfaultfd.c | 2 +-
> 3 files changed, 3 insertions(+), 3 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason