Hi Alistair,

On Tue, 10 Sept 2024 at 12:21, Alistair Popple [off-list ref] wrote:

Now that DAX and all other reference counts to ZONE_DEVICE pages are
managed normally there is no need for the special devmap PTE/PMD/PUD
page table bits. So drop all references to these, freeing up a
software defined page table bit on architectures supporting it.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: Will Deacon <will@kernel.org> # arm64
---
 Documentation/mm/arch_pgtable_helpers.rst     |  6 +--
 arch/arm64/Kconfig                            |  1 +-
 arch/arm64/include/asm/pgtable-prot.h         |  1 +-
 arch/arm64/include/asm/pgtable.h              | 24 +--------
 arch/powerpc/Kconfig                          |  1 +-
 arch/powerpc/include/asm/book3s/64/hash-4k.h  |  6 +--
 arch/powerpc/include/asm/book3s/64/hash-64k.h |  7 +--
 arch/powerpc/include/asm/book3s/64/pgtable.h  | 52 +------------------
 arch/powerpc/include/asm/book3s/64/radix.h    | 14 +-----
 arch/x86/Kconfig                              |  1 +-
 arch/x86/include/asm/pgtable.h                | 50 +-----------------
 arch/x86/include/asm/pgtable_types.h          |  5 +--

RISC-V's references also need to be cleanup, it simply can be done by
reverting the commit

216e04bf1e4d (riscv: mm: Add support for ZONE_DEVICE)

Thanks,
Chunyan

 include/linux/mm.h                            |  7 +--
 include/linux/pfn_t.h                         | 20 +-------
 include/linux/pgtable.h                       | 19 +------
 mm/Kconfig                                    |  4 +-
 mm/debug_vm_pgtable.c                         | 59 +--------------------
 mm/hmm.c                                      |  3 +-
 18 files changed, 11 insertions(+), 269 deletions(-)