Re: [PATCH v2 2/2] Documentation/vmcoreinfo: Add documentation for 'KERNELPACMASK'

[Will Deacon]

On Mon, Apr 27, 2020 at 11:55:02AM +0530, Amit Daniel Kachhap wrote:
> Add documentation for KERNELPACMASK variable being added to the vmcoreinfo.
> 
> It indicates the PAC bits mask information of signed kernel pointers if
> Armv8.3-A Pointer Authentication feature is present.
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Dave Young <dyoung@xxxxxxxxxx>
> Cc: Baoquan He <bhe@xxxxxxxxxx>
> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@xxxxxxx>
> ---
>  Documentation/admin-guide/kdump/vmcoreinfo.rst | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst
> index 007a6b8..5cc3ee6 100644
> --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst
> +++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst
> @@ -393,6 +393,12 @@ KERNELOFFSET
>  The kernel randomization offset. Used to compute the page offset. If
>  KASLR is disabled, this value is zero.
>  
> +KERNELPACMASK
> +-------------
> +
> +Indicates the PAC bits mask information if Pointer Authentication is
> +enabled and address authentication feature is present.

This is a bit cryptic. How about:

  The mask to extract the Pointer Authentication Code from a kernel virtual
  address.

Will