The sysfs attributes for the 24x7 counters are dynamically allocated.
Initialize the attributes using sysfs_attr_init() to fix following
warning which occurs when CONFIG_DEBUG_LOCK_VMALLOC=y.

[    0.346249] audit: initializing netlink subsys (disabled)
[    0.346284] audit: type=2000 audit(1436295254.340:1): initialized
[    0.346489] BUG: key c0000000efe90198 not in .data!
[    0.346491] DEBUG_LOCKS_WARN_ON(1)
[    0.346502] ------------[ cut here ]------------
[    0.346504] WARNING: at ../kernel/locking/lockdep.c:3002
[    0.346506] Modules linked in:

Reported-by: Gustavo Luiz Duarte <gustavold@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Tested-by: Gustavo Luiz Duarte <gustavold@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

core_idle_state is maintained for each core. It uses 0-7 bits to track
whether a thread in the core has entered fastsleep or winkle. 8th bit is
used as a lock bit.
The lock bit is set in these 2 scenarios-
 - The thread is first in subcore to wakeup from sleep/winkle.
 - If its the last thread in the core about to enter sleep/winkle

While the lock bit is set, if any other thread in the core wakes up, it
loops until the lock bit is cleared before proceeding in the wakeup
path. This helps prevent race conditions w.r.t fastsleep workaround and
prevents threads from switching to process context before core/subcore
resources are restored.

But, in the path to sleep/winkle entry, we currently don't check for
lock-bit. This exposes us to following race when running with subcore
on-

First thread in the subcorea		Another thread in the same
waking up		   		core entering sleep/winkle

lwarx   r15,0,r14
ori     r15,r15,PNV_CORE_IDLE_LOCK_BIT
stwcx.  r15,0,r14
[Code to restore subcore state]

						lwarx   r15,0,r14
						[clear thread bit]
						stwcx.  r15,0,r14

andi.   r15,r15,PNV_CORE_IDLE_THREAD_BITS
stw     r15,0(r14)

Here, after the thread entering sleep clears its thread bit in
core_idle_state, the value is overwritten by the thread waking up.
In such cases when the core enters fastsleep, code mistakes an idle
thread as running. Because of this, the first thread waking up from
fastsleep which is supposed to resync timebase skips it. So we can
end up having a core with stale timebase value.

This patch fixes the above race by looping on the lock bit even while
entering the idle states.

Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Fixes: 7b54e9f213f76 'powernv/powerpc: Add winkle support for offline cpus'
Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The conversion of opal events to a proper irqchip means that handlers
are called until the relevant opal event has been cleared by
processing it. Events that queue work should therefore use a threaded
handler to mask the event until processing is complete.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

An earlier commit referenced 'hose_list' in sysdev/ppc4xx_hsta_msi.c.
hose_list is defined in ppc-pci.h, which was not included in that
file. Include it, fixing the build for the akebono defconfig used
by the kbuild test robot.

Fixes: f2c800aaceb6 ("powerpc/ppc4xx_hsta_msi: Move MSI-related ops to pci_controller_ops")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

If we take an alignment exception which we cannot fix, the oops
currently prints:

Unable to handle kernel paging request for unknown fault

Lets print something more useful:

Unable to handle kernel paging request for unaligned access at address 0xc0000000f77bba8f

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This means the 'M' flag will work properly when the kernel prints a backtrace.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

opal-prd driver will mmap() firmware code/data area as private
mapping to prd user space daemon.  Write to this page will
trigger COW faults.  The new COW pages are normal kernel RAM
pages accounted by the kernel and are not special.

vma->vm_page_prot value will be used at page fault time
for the new COW pages, while pgprot_t value passed in
remap_pfn_range() is used for the initial page table entry.

Hence:
* Do not add _PAGE_SPECIAL in vma, but only for remap_pfn_range()
* Also remap_pfn_range() will add the _PAGE_SPECIAL flag using
  pte_mkspecial() call, hence no need to specify in the driver

This fix resolves the page accounting warning shown below:
BUG: Bad rss-counter state mm:c0000007d34ac600 idx:1 val:19

The above warning is triggered since _PAGE_SPECIAL was incorrectly
being set for the normal kernel COW pages.

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pull more vfs updates from Al Viro:
 "Assorted VFS fixes and related cleanups (IMO the most interesting in
  that part are f_path-related things and Eric's descriptor-related
  stuff).  UFS regression fixes (it got broken last cycle).  9P fixes.
  fs-cache series, DAX patches, Jan's file_remove_suid() work"

[ I'd say this is much more than "fixes and related cleanups".  The
  file_table locking rule change by Eric Dumazet is a rather big and
  fundamental update even if the patch isn't huge.   - Linus ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
  9p: cope with bogus responses from server in p9_client_{read,write}
  p9_client_write(): avoid double p9_free_req()
  9p: forgetting to cancel request on interrupted zero-copy RPC
  dax: bdev_direct_access() may sleep
  block: Add support for DAX reads/writes to block devices
  dax: Use copy_from_iter_nocache
  dax: Add block size note to documentation
  fs/file.c: __fget() and dup2() atomicity rules
  fs/file.c: don't acquire files->file_lock in fd_install()
  fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
  vfs: avoid creation of inode number 0 in get_next_ino
  namei: make set_root_rcu() return void
  make simple_positive() public
  ufs: use dir_pages instead of ufs_dir_pages()
  pagemap.h: move dir_pages() over there
  remove the pointless include of lglock.h
  fs: cleanup slight list_entry abuse
  xfs: Correctly lock inode when removing suid and file capabilities
  fs: Call security_ops->inode_killpriv on truncate
  fs: Provide function telling whether file_remove_privs() will do anything
  ...

Pull module_init replacement part two from Paul Gortmaker:
 "Replace module_init with appropriate alternate initcall in non
  modules.

  This series converts non-modular code that is using the module_init()
  call to hook itself into the system to instead use one of our
  alternate priority initcalls.

  Unlike the previous series that used device_initcall and hence was a
  runtime no-op, these commits change to one of the alternate initcalls,
  because (a) we have them and (b) it seems like the right thing to do.

  For example, it would seem logical to use arch_initcall for arch
  specific setup code and fs_initcall for filesystem setup code.

  This does mean however, that changes in the init ordering will be
  taking place, and so there is a small risk that some kind of implicit
  init ordering issue may lie uncovered.  But I think it is still better
  to give these ones sensible priorities than to just assign them all to
  device_initcall in order to exactly preserve the old ordering.

  Thad said, we have already made similar changes in core kernel code in
  commit c96d6660dc65 ("kernel: audit/fix non-modular users of
  module_init in core code") without any regressions reported, so this
  type of change isn't without precedent.  It has also got the same
  local testing and linux-next coverage as all the other pull requests
  that I'm sending for this merge window have got.

  Once again, there is an unused module_exit function removal that shows
  up as an outlier upon casual inspection of the diffstat"

* tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  x86: perf_event_intel_pt.c: use arch_initcall to hook in enabling
  x86: perf_event_intel_bts.c: use arch_initcall to hook in enabling
  mm/page_owner.c: use late_initcall to hook in enabling
  lib/list_sort: use late_initcall to hook in self tests
  arm: use subsys_initcall in non-modular pl320 IPC code
  powerpc: don't use module_init for non-modular core hugetlb code
  powerpc: use subsys_initcall for Freescale Local Bus
  x86: don't use module_init for non-modular core bootflag code
  netfilter: don't use module_init/exit in core IPV4 code
  fs/notify: don't use module_init for non-modular inotify_user code
  mm: replace module_init usages with subsys_initcall in nommu.c

Pull module_init replacement part one from Paul Gortmaker:
 "Replace module_init with equivalent device_initcall in non modules.

  This series of commits converts non-modular code that is using the
  module_init() call to hook itself into the system to instead use
  device_initcall().

  The conversion is a runtime no-op, since module_init actually becomes
  __initcall in the non-modular case, and that in turn gets mapped onto
  device_initcall.  A couple files show a larger negative diffstat,
  representing ones that had a module_exit function that we remove here
  vs previously relying on the linker to dispose of it.

  We make this conversion now, so that we can relocate module_init from
  init.h into module.h in the future.

  The files changed here are just limited to those that would otherwise
  have to add module.h to obviously non-modular code, in order to avoid
  a compile fail, as testing has shown"

* tag 'module_init-device_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  MIPS: don't use module_init in non-modular cobalt/mtd.c file
  drivers/leds: don't use module_init in non-modular leds-cobalt-raq.c
  cris: don't use module_init for non-modular core eeprom.c code
  tty/metag_da: Avoid module_init/module_exit in non-modular code
  drivers/clk: don't use module_init in clk-nomadik.c which is non-modular
  xtensa: don't use module_init for non-modular core network.c code
  sh: don't use module_init in non-modular psw.c code
  mn10300: don't use module_init in non-modular flash.c code
  parisc64: don't use module_init for non-modular core perf code
  parisc: don't use module_init for non-modular core pdc_cons code
  cris: don't use module_init for non-modular core intmem.c code
  ia64: don't use module_init in non-modular sim/simscsi.c code
  ia64: don't use module_init for non-modular core kernel/mca.c code
  arm: don't use module_init in non-modular mach-vexpress/spc.c code
  powerpc: don't use module_init in non-modular 83xx suspend code
  powerpc: use device_initcall for registering rtc devices
  x86: don't use module_init in non-modular devicetree.c code
  x86: don't use module_init in non-modular intel_mid_vrtc.c