# Re: \[PATCH 36/63\] powerpc: Book 3S MMU little endian support

- From: Paul Mackerras \<hidden\>
- Date: 2013-08-07 04:20:49 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2013/08/9475689
- Thread: https://ratatoskr.run/linuxppc-dev/2013/08/9475601/t.md

```text
On Wed, Aug 07, 2013 at 02:01:53AM +1000, Anton Blanchard wrote:

> +#ifdef __BIG_ENDIAN__
>  #define HPTE_LOCK_BIT 3
> +#else
> +#define HPTE_LOCK_BIT (63-3)
> +#endif

Are you deliberately using a different bit here?  AFAICS you are using
0x20 in the 7th byte as the lock bit for LE, whereas we use 0x08 in
that byte on BE.  Both are software-use bits, so it will still work,
but is there a rationale for the change?  Or did you mean (56+3)
rather than (63-3)?

Paul.
```