[v2] powerpc/perf: Fix kernel address leak to userspace via BHRB buffer

[Michael Ellerman]

On Wed, 2018-03-21 at 11:40:25 UTC, Madhavan Srinivasan wrote:
> The current Branch History Rolling Buffer (BHRB) code does
> not check for any privilege levels before updating the data
> from BHRB. This leaks kernel addresses to userspace even when
> profiling only with userspace privileges. Add proper checks
> to prevent it.
> 
> Acked-by: Balbir Singh <bsingharora at gmail.com>
> Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/bb19af816025d495376bd76bf6fbcf

cheers