Re: [PATCH v3 2/2] xen: arm: Be explicit about bit values in mfn_to_xen_entry()

[Ian Campbell <ian.campbell@citrix.com>]

On Thu, 2015-09-10 at 11:56 -0700, Chris Brand wrote:
> Ensure that every relevant bit is given an explicit value.
> This has no effect on the generated code, but makes it
> a little easier to follow.
> 
> Reported-by: Julien Grall <julien.grall@citrix.com>
> Signed-off-by: Chris Brand <chris.brand@broadcom.com>

Acked + applied for 4.7 along with the first one.

I don't think there is any need for either for 4.6, since it's just a code
clarity thing.

> ---
> v3 trims down the list of bits given explicit values
> v2 adds comments on pxn and avail
> 
>  xen/include/asm-arm/page.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/xen/include/asm-arm/page.h b/xen/include/asm-arm/page.h
> index 01628f3e96cb..a94e978a9995 100644
> --- a/xen/include/asm-arm/page.h
> +++ b/xen/include/asm-arm/page.h
> @@ -202,9 +202,12 @@ static inline lpae_t mfn_to_xen_entry(unsigned long
> mfn, unsigned attr)
>              .ai = attr,
>              .ns = 1,              /* Hyp mode is in the non-secure world
> */
>              .user = 1,            /* See below */
> +            .ro = 0,              /* Assume read-write */
>              .af = 1,              /* No need for access tracking */
>              .ng = 1,              /* Makes TLB flushes easier */
> +            .contig = 0,          /* Assume non-contiguous */
>              .xn = 1,              /* No need to execute outside .text */
> +            .avail = 0,           /* Reference count for domheap mapping
> */
>          }};;
>      /* Setting the User bit is strange, but the ATS1H[RW] instructions
>       * don't seem to work otherwise, and since we never run on Xen