Re: [RFC v6 11/62] powerpc: initial pkey plumbing

From: Aneesh Kumar K.V
Date: Thu Jul 20 2017 - 02:05:59 EST


Ram Pai <linuxram@xxxxxxxxxx> writes:

> basic setup to initialize the pkey system. Only 64K kernel in HPT
> mode, enables the pkey system.
>
> Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
> ---
> arch/powerpc/Kconfig | 16 ++++++++++
> arch/powerpc/include/asm/mmu_context.h | 5 +++
> arch/powerpc/include/asm/pkeys.h | 51 ++++++++++++++++++++++++++++++++
> arch/powerpc/kernel/setup_64.c | 4 ++
> arch/powerpc/mm/Makefile | 1 +
> arch/powerpc/mm/hash_utils_64.c | 1 +
> arch/powerpc/mm/pkeys.c | 18 +++++++++++
> 7 files changed, 96 insertions(+), 0 deletions(-)
> create mode 100644 arch/powerpc/include/asm/pkeys.h
> create mode 100644 arch/powerpc/mm/pkeys.c
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index bf4391d..5c60fd6 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -855,6 +855,22 @@ config SECCOMP
>
> If unsure, say Y. Only embedded should say N here.
>
> +config PPC64_MEMORY_PROTECTION_KEYS
> + prompt "PowerPC Memory Protection Keys"
> + def_bool y
> + # Note: only available in 64-bit mode
> + depends on PPC64 && PPC_64K_PAGES
> + select ARCH_USES_HIGH_VMA_FLAGS
> + select ARCH_HAS_PKEYS
> + ---help---
> + Memory Protection Keys provides a mechanism for enforcing
> + page-based protections, but without requiring modification of the
> + page tables when an application changes protection domains.
> +
> + For details, see Documentation/vm/protection-keys.txt
> +
> + If unsure, say y.
> +
> endmenu


Shouldn't this come as the last patch ? Or can we enable this config by
this patch ? If so what does it do ? Did you test boot each of this
patch to make sure we don't break git bisect ?

>
> config ISA_DMA_API
> diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
> index da7e943..4b93547 100644
> --- a/arch/powerpc/include/asm/mmu_context.h
> +++ b/arch/powerpc/include/asm/mmu_context.h
> @@ -181,5 +181,10 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
> /* by default, allow everything */


-aneesh