Re: [PATCHv5, REBASED 8/9] x86: Enable 5-level paging support

From: Juergen Gross
Date: Mon May 15 2017 - 08:31:11 EST


On 15/05/17 14:12, Kirill A. Shutemov wrote:
> Most of things are in place and we can enable support of 5-level paging.
>
> Enabling XEN with 5-level paging requires more work. The patch makes XEN
> dependent on !X86_5LEVEL.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> ---
> arch/x86/Kconfig | 5 +++++
> arch/x86/xen/Kconfig | 1 +
> 2 files changed, 6 insertions(+)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index cd18994a9555..11bd0498f64c 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -318,6 +318,7 @@ config FIX_EARLYCON_MEM
>
> config PGTABLE_LEVELS
> int
> + default 5 if X86_5LEVEL
> default 4 if X86_64
> default 3 if X86_PAE
> default 2
> @@ -1390,6 +1391,10 @@ config X86_PAE
> has the cost of more pagetable lookup overhead, and also
> consumes more pagetable space per process.
>
> +config X86_5LEVEL
> + bool "Enable 5-level page tables support"
> + depends on X86_64
> +
> config ARCH_PHYS_ADDR_T_64BIT
> def_bool y
> depends on X86_64 || X86_PAE
> diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
> index 027987638e98..12205e6dfa59 100644
> --- a/arch/x86/xen/Kconfig
> +++ b/arch/x86/xen/Kconfig
> @@ -5,6 +5,7 @@
> config XEN
> bool "Xen guest support"
> depends on PARAVIRT
> + depends on !X86_5LEVEL

I'd rather put this under "config XEN_PV".


Juergen