selftests/powerpc: Add a test of wild bctr

[Michael Ellerman]

On Tue, 2018-07-24 at 05:53:22 UTC, Michael Ellerman wrote:
> This tests that a bctr (Branch to counter and link), ie. a function
> call, to a wildly out-of-bounds address is handled correctly.
> 
> Some old kernel versions didn't handle it correctly, see eg:
> 
>   "powerpc/slb: Force a full SLB flush when we insert for a bad EA"
>   https://lists.ozlabs.org/pipermail/linuxppc-dev/2017-April/157397.html
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/b7683fc66eba91674e52c30f4d8e59

cheers