[PATCH kernel] powerpc/perf: Stop crashing with generic_compat_pmu

[Michael Ellerman]

On Tue, 2 Jun 2020 12:56:12 +1000, Alexey Kardashevskiy wrote:
> The bhrb_filter_map ("The  Branch  History  Rolling  Buffer") callback is
> only defined in raw CPUs' power_pmu structs. The "architected" CPUs use
> generic_compat_pmu which does not have this callback and crashed occur.
> 
> This add a NULL pointer check for bhrb_filter_map() which behaves as if
> the callback returned an error.
> 
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/perf: Fix crashes with generic_compat_pmu & BHRB
      https://git.kernel.org/powerpc/c/b460b512417ae9c8b51a3bdcc09020cd6c60ff69

cheers