Re: [PATCH] alpha: Add ARCH_HAS_PTE_SPECIAL support

[Michael Cree <mcree@orcon.net.nz>]

Hi Matt,

On Fri, Apr 03, 2026 at 11:00:48AM -0400, Matt Turner wrote:
> Add _PAGE_SPECIAL using bit 19 (0x80000), which is unused in the Alpha
> PTE layout. This enables pte_special()/pte_mkspecial() for marking PTEs
> that are not backed by struct page (VDSO mappings, zero page,
> io_remap_pfn_range, etc.).
> 
> Include _PAGE_SPECIAL in _PAGE_CHG_MASK so it is preserved across
> pte_modify() calls.
> 
> Assisted-by: Claude:claude-opus-4-6
> Signed-off-by: Matt Turner <mattst88@gmail.com>
> ---
>  arch/alpha/Kconfig               | 1 +
>  arch/alpha/include/asm/pgtable.h | 5 ++++-
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git ./arch/alpha/Kconfig ./arch/alpha/Kconfig
> index a5feb98cc088..a29788e588ee 100644
> --- ./arch/alpha/Kconfig
> +++ ./arch/alpha/Kconfig
> @@ -8,6 +8,7 @@ config ALPHA
>  	select ARCH_HAS_FAST_MULTIPLIER
>  	select ARCH_HAS_GCOV_PROFILE_ALL
>  	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> +	select ARCH_HAS_PTE_SPECIAL
>  	select ARCH_HAS_UBSAN
>  	select ARCH_MIGHT_HAVE_PC_PARPORT
>  	select ARCH_MIGHT_HAVE_PC_SERIO

On what kernel does this patch apply?  My master branch has none of:

ARCH_HAS_FAST_MULTIPLIER
ARCH_HAS_GCOV_PROFILE_ALL
ARCH_HAS_UBSAN

and they don't seem to be added at all in the other patches you sent.

Cheers,
Michael.