Comment 0 for bug 1759312

---Problem Description---
AT_BASE_PLATFORM in AUXV is absent on kernels available on Ubuntu 17.10

---Additional Hardware Info---
Architecture: ppc64le
Byte Order: Little Endian
CPU(s): 176
On-line CPU(s) list: 0-175
Thread(s) per core: 4
Core(s) per socket: 22
Socket(s): 2
NUMA node(s): 8
Model: 2.2 (pvr 004e 1202)
Model name: POWER9, altivec supported
CPU max MHz: 2800.0000
CPU min MHz: 2300.0000
L1d cache: 32K
L1i cache: 32K
L2 cache: 512K
L3 cache: 10240K
NUMA node0 CPU(s): 0-87
NUMA node8 CPU(s): 88-175
NUMA node250 CPU(s):
NUMA node251 CPU(s):
NUMA node252 CPU(s):
NUMA node253 CPU(s):
NUMA node254 CPU(s):
NUMA node255 CPU(s):

Machine Type = P9, DD2.2, Witherspoon, baremetal

---Steps to Reproduce---
 AT_BASE_PLATFORM in AIXV is not exported to userspace on P9 baremetal machines causing trouble to userspace tools and software that relie on that information, notably operf and opreport (from oprofile 1.2.0+) will refuse to run without that information show a error message like:

gromero@ltc-wspoon3:/boot$ operf
NULL returned for one or both of AT_PLATFORM/AT_BASE_PLATFORM
AT_PLATFORM: power9; AT_BASE_PLATFORM: (null)
Unable to obtain cpu_type
Verify that a pre-1.0 version of OProfile is not in use.
If the /dev/oprofile/cpu_type file exists, locate the pre-1.0 OProfile
installation, and use its 'opcontrol' command, passing the --deinit option.
Unable to ascertain cpu type. Exiting.

---uname output---
linux-image-4.13.0-36-generic 4.13.0-36.40

Userspace tool common name: operf, opreport

Dear maintainer. please consider applying the following fix that's already available upstream:

https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=e4b79900222b8cccd4da4a7a89581f

Thank you.