On 14/09/2026 14:51, Muhammad Usama Anjum wrote:
> Hi,
>
> The generic series introduces hw_pte_t for HW PTEs, while SW PTE values
> use pte_t. This series enables the distinct type on arm64 so the
> compiler can distinguish HW PTE pointers (hw_pte_t *) from SW PTE value
> pointers (pte_t *).
>
> The conversion updates HW PTE pointers and accessors, including atomic
> updates, fixmap, and early page-table construction, before selecting
> ARCH_HAS_HW_PTE_T. Higher-level entry types remain out of scope, and
> shared helpers retain explicit casts.
>
> The linked generic series is a prerequisite. Its cover contains the
> Coccinelle script used for most pointer conversions; the remaining sites
> were converted by hand.
>
> Link: https://lore.kernel.org/all/20260903103002.1091859-1-usama.anjum@arm.com/
> Signed-off-by: Muhammad Usama Anjum <usama.anjum@arm.com>
I've been through this as best I can and provided some minor comments. This all
looks ok over all. But given the number of small changes, it would probably be
wise to go big on testing; what level of testing has been performed? I'd suggest
mm selftests (with all the magic to make all the tests actually run) at minimum
and all the fastpath benchmarks as a stress test.
I think it's quite ugly (and adds a bit to the cognitive load) to have this
intermediate state where only ptes are converted. But I understand the need to
do this incrementally. Hopefully you can follow up with the other levels soon :)
Thanks,
Ryan
> ---
> Muhammad Usama Anjum (6):
> arm64: use hw_pte_t for HW PTE pointers
> arm64: use hw_pte_val for HW PTE atomics
> arm64: convert between HW PTEs and SW PTE values
> arm64: use hw_pte_t for fixmap HW PTEs
> arm64: use HW PTE accessors in early map_range()
> arm64: enable a distinct type for HW PTEs
>
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/hugetlb.h | 19 ++---
> arch/arm64/include/asm/pgalloc.h | 2 +-
> arch/arm64/include/asm/pgtable.h | 157 ++++++++++++++++++++------------------
> arch/arm64/include/asm/vmalloc.h | 2 +-
> arch/arm64/kernel/efi.c | 3 +-
> arch/arm64/kernel/pi/map_kernel.c | 4 +-
> arch/arm64/kernel/pi/map_range.c | 20 +++--
> arch/arm64/kernel/pi/pi.h | 3 +-
> arch/arm64/mm/contpte.c | 49 ++++++------
> arch/arm64/mm/fault.c | 11 +--
> arch/arm64/mm/fixmap.c | 8 +-
> arch/arm64/mm/hugetlbpage.c | 48 ++++++------
> arch/arm64/mm/kasan_init.c | 4 +-
> arch/arm64/mm/mmu.c | 46 ++++++-----
> arch/arm64/mm/pageattr.c | 4 +-
> arch/arm64/mm/trans_pgd.c | 4 +-
> include/linux/pgtable_types.h | 6 ++
> 18 files changed, 215 insertions(+), 176 deletions(-)
> ---
> base-commit: ead700ca770c82167af32622cf8b68c9f87c3c7c
> change-id: 20260911-pte0_arm-f1b7df7c0b51
> prerequisite-message-id: 20260903103002.1091859-1-usama.anjum@arm.com
> prerequisite-patch-id: 0114fcc6ab0dbb739b5bb6fc0fe6b1c8f1fa37a1
> prerequisite-patch-id: 09fcf65970074620dd3a9cce6850b901beb01db8
> prerequisite-patch-id: 9b2fdab97c99effabb85526fa7f141c933b3aa23
> prerequisite-patch-id: 1aa309a26d98a1e93a54742705a03567ee93be71
> prerequisite-patch-id: ebe32f52c95ad0542982f0b37798d209595e25e1
> prerequisite-patch-id: a60d249f52d092524176851b2570d7245bb24434
> prerequisite-patch-id: 81ebd1378e25d40a1771b53973abcc4defa87535
> prerequisite-patch-id: d982f2b00c5eddb2459f69008a73e4f4ae4d8299
>
> Best regards,
> --
> Usama
>