[SRU][Zesty][PATCH 0/4] Fixes for LP:1685792

[Joseph Salisbury]

BugLink: http://bugs.launchpad.net/bugs/1685792

== SRU Justification ==
Power9 DD1 has a hardware issue that when all threads are 
offlined  and then any of the CPUs are onlined, they come online with an 
incorrect PACA thereby resulting in a crash.

These four patches are in mainline as of v4.12-rc1.  They are needed to get 
CPU-Hotplug working correctly on a Power9 DD1 system.

The first three patches are clean cherry picks, but the fourth required
a minor backport.

== Fixes ==
commit a7cd88da97040513e17cd77ae3e57764e854bae4
Author: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
Date:   Wed Mar 22 20:34:14 2017 +0530

    powerpc/powernv: Move CPU-Offline idle state invocation from smp.c to idle.c

commit 9006123157886acc47bdc17e26c933d710b8d6cd
Author: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
Date:   Wed Mar 22 20:34:15 2017 +0530

    powerpc/powernv/smp: Add busy-wait loop as fall back for CPU-Hotplug

commit f3b3f28493d93232a37d5fbb5cb5ad168ede0e1a
Author: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
Date:   Wed Mar 22 20:34:16 2017 +0530

    powerpc/powernv/idle: Don't override default/deepest directly in kernel

commit 17ed4c8f81da2bf340d33a8c875f4d6b1dfd9398
Author: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
Date:   Wed Mar 22 20:34:17 2017 +0530

    powerpc/powernv: Recover correct PACA on wakeup from a stop on P9 DD1


== Test Case ==
A test kernel was built with these patches and tested by the original bug reporter.
The bug reporter states the test kernel resolved the bug.

Gautham R. Shenoy (4):
  powerpc/powernv: Move CPU-Offline idle state invocation from smp.c to
    idle.c
  powerpc/powernv/smp: Add busy-wait loop as fall back for CPU-Hotplug
  powerpc/powernv/idle: Don't override default/deepest directly in
    kernel
  powerpc/powernv: Recover correct PACA on wakeup from a stop on P9 DD1

 arch/powerpc/include/asm/cpuidle.h       |  1 +
 arch/powerpc/include/asm/paca.h          |  5 ++
 arch/powerpc/kernel/asm-offsets.c        |  2 +
 arch/powerpc/kernel/idle_book3s.S        | 48 +++++++++++++++-
 arch/powerpc/platforms/powernv/idle.c    | 96 ++++++++++++++++++++++++++------
 arch/powerpc/platforms/powernv/powernv.h |  2 -
 arch/powerpc/platforms/powernv/smp.c     | 18 +-----
 7 files changed, 137 insertions(+), 35 deletions(-)

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2.7.4