If store_mem_state() is called to online memory which is already online,
it will return 1, the value it got from device_online().

This is wrong because store_mem_state() is a device_attribute .store
function.  Thus a non-negative return value represents input bytes read.

Set the return value to -EINVAL in this case.

Link: http://lkml.kernel.org/r/1472743777-24266-1-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull pin control updates from Linus Walleij:
 "This is the bulk of pin control changes for the v4.9 cycle.

  General improvements:

   - nicer debugfs output with one pin/config pair per line.

   - continued efforts to strictify module vs bool.

   - constification and similar from Coccinelle engineers.

   - return error from pinctrl_bind_pins()

   - pulling in the ability to selectively disable mapping of unusable
     IRQs from the GPIO subsystem.

  New drivers:

   - new driver for the Aspeed pin controller family: AST2400 (G4) and
     AST2500 (G5) are supported. These are used by OpenBMC on the IBM
     Witherspoon platform.

   - new subdriver for the Allwinner sunxi GR8.

  Driver improvements:

   - drop default IRQ trigger types assigned during IRQ mapping on AT91
     and Nomadik. This error was identified by improvements in the IRQ
     core by Marc Zyngier.

   - active high/low types on the GPIO IRQs for the ST pin controller.

   - IRQ support on GPIOs on the STM32 pin controller.

   - Renesas Super-H/ARM sh-pfc: continued massive developments.

   - misc MXC improvements.

   - SPDIF on the Allwiner A31 SoC

   - IR remote and SPI NOR flash, NAND flash, I2C pins on the AMLogic
     SoC.

   - PWM pins on the Meson.

   - do not map unusable IRQs (taken by BIOS) on the Intel Cherryview.

   - add GPIO IRQ wakeup support to the Intel driver so we can wake up
     from button pushes.

  Deprecation:

   - delete the obsolete STiH415/6 SoC support"

* tag 'pinctrl-v4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (75 commits)
  pinctrl: qcom: fix masking of pinmux functions
  pinctrl: intel: Configure GPIO chip IRQ as wakeup interrupts
  pinctrl: cherryview: Convert to use devm_gpiochip_add_data()
  pinctrl: cherryview: Do not add all southwest and north GPIOs to IRQ domain
  gpiolib: Make it possible to exclude GPIOs from IRQ domain
  pinctrl: nomadik: don't default-flag IRQs as falling
  pinctrl: st: Remove obsolete platforms from pinctrl-st dt doc
  pinctrl: st: Remove STiH415/6 SoC pinctrl driver support.
  pinctrl: amlogic: gxbb: add i2c pins
  pinctrl: amlogic: gxbb: add nand pins
  pinctrl: stm32: add IRQ_DOMAIN_HIERARCHY dependency
  pinctrl: amlogic: gxbb: add spi nor pins
  pinctrl: sh-pfc: r8a7794: Implement voltage switching for SDHI
  pinctrl: sh-pfc: r8a7791: Implement voltage switching for SDHI
  pinctrl: sh-pfc: Add PORT_GP_24 helper macro
  pinctrl: Fix "st,syscfg" definition for STM32 pinctrl
  driver: base: pinctrl: return error from pinctrl_bind_pins()
  pinctrl: meson-gxbb: add the missing SDIO interrupt pin
  pinctrl: aspeed: fix regmap error handling
  pinctrl: mediatek: constify gpio_chip structures
  ...

Pull regmap updates from Mark Brown:
 "Another quiet release, a few small extensions to the set of register
  maps we support and an improvement in the debugfs code:

   - allow viewing of cached contents for write only registers via
     debugfs.

   - support a wider range of read/write flag masks in register formats.

   - support more little endian formats"

* tag 'regmap-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: Add missing little endian functions
  regmap: Allow longer flag masks for read and write
  regmap: debugfs: Add support for dumping write only device registers
  regmap: Add a function to check if a regmap register is cached

Pull driver core updates from Greg KH:
 "Here are the "big" driver core patches for 4.9-rc1. Also in here are a
  number of debugfs fixes that cropped up due to the changes that
  happened in 4.8 for that filesystem. Overall, nothing major, just a
  few fixes and cleanups.

  All of these have been in linux-next with no reported issues"

* tag 'driver-core-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
  drivers: dma-coherent: Move spinlock in dma_alloc_from_coherent()
  drivers: dma-coherent: Fix DMA coherent size for less than page
  MAINTAINERS: extend firmware_class maintainer list
  debugfs: propagate release() call result
  driver-core: platform: Catch errors from calls to irq_get_irq_data
  sysfs print name of undiscoverable attribute group
  carl9170: fix debugfs crashes
  b43legacy: fix debugfs crash
  b43: fix debugfs crash
  debugfs: introduce a public file_operations accessor
  device core: Remove deprecated create_singlethread_workqueue
  drivers/base dmam_declare_coherent_memory leaks
  platform: don't return 0 from platform_get_irq[_byname]() on error
  cpu: clean up register_cpu func
  dma-mapping: use vma_pages().
  drivers: dma-coherent: use vma_pages().
  attribute_container: Fix typo
  base: soc: make it explicitly non-modular
  drivers: base: dma-mapping: page align the size when unmap_kernel_range
  platform driver: fix use-after-free in platform_device_del()
  ...

Pull irq updates from Thomas Gleixner:
 "The irq departement proudly presents:

   - A rework of the core infrastructure to optimally spread interrupt
     for multiqueue devices. The first version was a bit naive and
     failed to take thread siblings and other details into account.
     Developed in cooperation with Christoph and Keith.

   - Proper delegation of softirqs to ksoftirqd, so if ksoftirqd is
     active then no further softirq processsing on interrupt return
     happens. Otherwise we try to delegate and still run another batch
     of network packets in the irq return path, which then tries to
     delegate to ksoftirqd .....

   - A proper machine parseable sysfs based alternative for
     /proc/interrupts.

   - ACPI support for the GICV3-ITS and ARM interrupt remapping

   - Two new irq chips from the ARM SoC zoo: STM32-EXTI and MVEBU-PIC

   - A new irq chip for the JCore (SuperH)

   - The usual pile of small fixlets in core and irqchip drivers"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
  softirq: Let ksoftirqd do its job
  genirq: Make function __irq_do_set_handler() static
  ARM/dts: Add EXTI controller node to stm32f429
  ARM/STM32: Select external interrupts controller
  drivers/irqchip: Add STM32 external interrupts support
  Documentation/dt-bindings: Document STM32 EXTI controller bindings
  irqchip/mips-gic: Use for_each_set_bit to iterate over local IRQs
  pci/msi: Retrieve affinity for a vector
  genirq/affinity: Remove old irq spread infrastructure
  genirq/msi: Switch to new irq spreading infrastructure
  genirq/affinity: Provide smarter irq spreading infrastructure
  genirq/msi: Add cpumask allocation to alloc_msi_entry
  genirq: Expose interrupt information through sysfs
  irqchip/gicv3-its: Use MADT ITS subtable to do PCI/MSI domain initialization
  irqchip/gicv3-its: Factor out PCI-MSI part that might be reused for ACPI
  irqchip/gicv3-its: Probe ITS in the ACPI way
  irqchip/gicv3-its: Refactor ITS DT init code to prepare for ACPI
  irqchip/gicv3-its: Cleanup for ITS domain initialization
  PCI/MSI: Setup MSI domain on a per-device basis using IORT ACPI table
  ACPI: Add new IORT functions to support MSI domain handling
  ...

Pull ACPI updates from Rafael Wysocki:
 "First off, the ACPICA code in the kernel is updated to upstream
  revision 20160831 that brings in a few bug fixes and cleanups. In
  particular, it is possible to mask GPEs now (and the sysfs interface
  for GPE control is fixed on top of that), problems related to the
  table loading mechanism are fixed and all code related to FADT version
  2 (which has never been part of the ACPI specification) is dropped.

  On the new features front, there is a new watchdog driver based on the
  ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to
  replace the iTCO watchdog that doesn't work there, and some UART
  devices get new definitions of built-in properties (to be accessed via
  the generic device properties API).

  Also, included is a fix for an ACPI-related PCI resorces allocation
  issue and a few problems in the EC driver and in the button and
  battery drivers are fixed.

  In addition to that, the ACPI CPPC library is updated to make batching
  of requests sent over the PCC channel possible (which reduces the PCC
  usage overhead substantially in some cases) and to support functional
  fixed hardware (FFH) type of CPPC registers access (which will allow
  CPPC to be used on x86 too in the future).

  As usual, there are some assorted fixes and cleanups too.

  Specifics:

   - Update of the ACPICA code in the kernel to upstream revision
     20160831 with the following major changes:

      * New mechanism for GPE masking.
      * Fixes for issues related to the LoadTable operator and table
        loading.
      * Fixes for issues related to so-called module-level code (MLC),
        that is AML that doesn't belong to any methods.
      * Change of the return value of the _OSI method to reflect the
        Windows behavior.
      * GAS (Generic Address Structure) support fix related to 32-bit
        FADT addresses.
      * Elimination of unnecessary FADT version 2 support.
      * ACPI tools fixes and cleanups.

     From Bob Moore, Lv Zheng, and Jung-uk Kim.

   - ACPI sysfs interface updates to fix GPE handling (on top of the new
     GPE masking mechanism in ACPICA) and issues related to table
     loading (Lv Zheng).

   - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action
     Table), needed on some platforms to replace the iTCO watchdog that
     doesn't work there and related updates of the intel_pmc_ipc,
     i2c/i801 and MFD/lcp_ich drivers (Mika Westerberg).

   - Driver core fix to prevent it from leaking secondary fwnode objects
     during device removal (Lukas Wunner).

   - New definitions of built-in properties for UART in ACPI-based x86
     SoC drivers and a 8250_dw driver quirk for the APM X-Gene SoC
     (Heikki Krogerus).

   - New device ID for the Vulcan SPI controller and constification of
     local strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel,
     Julia Lawall).

   - Fix for a bug causing the allocation of PCI resorces to fail if
     ACPI-enumerated child platform devices are registered below the PCI
     devices in question (Mika Westerberg).

   - Change of the default polarity for PCI legacy IRQs to high on
     systems booting wth ACPI on platforms with a GIC interrupt
     controller model fixing the discrepancy between the specification
     and HW behavior (Lorenzo Pieralisi).

   - Fixes for the handling of system suspend/resume in the ACPI EC
     driver and update of that driver to make it cope with the cases
     when the EC device defined in the ECDT has to be used throughout
     the entire system life cycle (Lv Zheng).

   - Update of the ACPI CPPC library to allow it to batch requests sent
     over the PCC channel (to reduce overhead), to support the fixed
     functional hardware (FFH) CPPC registers access type, to notify the
     mailbox framework about TX completions when the interrupt flag is
     set for the PCC mailbox, and to support HW-Reduced Communication
     Subspace type 2 (Ashwin Chaugule, Prashanth Prakash, Srinivas
     Pandruvada, Hoan Tran).

   - ACPI button driver fix and documentation update related to the
     handling of laptop lids (Lv Zheng).

   - ACPI battery driver initialization fix (Carlos Garnacho).

   - ACPI GPIO enumeration documentation update (Mika Westerberg).

   - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv
     Zheng).

   - Assorted cleanups of the ACPI table parsing code and the
     x86-specific ACPI code (Al Stone).

   - Fixes for assorted ACPI-related issues found in linux-next (Wei
     Yongjun)"

* tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (98 commits)
  ACPI / documentation: Use recommended name in GPIO property names
  watchdog: wdat_wdt: Fix warning for using 0 as NULL
  watchdog: wdat_wdt: fix return value check in wdat_wdt_probe()
  platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists
  i2c: i801: Do not create iTCO watchdog when WDAT table exists
  mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists
  ACPI / bus: Adjust ACPI subsystem initialization for new table loading mode
  ACPICA: Parser: Fix a regression in LoadTable support
  ACPICA: Tables: Fix "UNLOAD" code path lock issues
  ACPI / watchdog: Add support for WDAT hardware watchdog
  ACPI / platform: Pay attention to parent device's resources
  PCI: Add pci_find_resource()
  ACPI / CPPC: Support PCC with interrupt flag
  ACPI / sysfs: Update sysfs signature handling code
  ACPI / sysfs: Fix an issue for LoadTable opcode
  ACPICA: Tables: Fix a regression in acpi_tb_find_table()
  ACPI / tables: Remove duplicated include from tables.c
  ACPI / APD: constify local structures
  x86: ACPI: make variable names clearer in acpi_parse_madt_lapic_entries()
  x86: ACPI: remove extraneous white space after semicolon
  ...

* pm-cpuidle:
  ARM: cpuidle: Fix error return code

* pm-opp:
  PM / OPP: Don't support OPP if it provides supported-hw but platform does not
  PM / OPP: avoid maybe-uninitialized warning

* pm-avs:
  PM / AVS: SmartReflex: Neaten logging

* pm-domains:
  PM / Domains: Rename pm_genpd_sync_poweron|poweroff()
  PM / Domains: Don't measure latency of ->power_on|off() during system PM
  PM / Domains: Remove redundant system PM callbacks
  PM / Domains: Simplify detaching a device from its genpd
  PM / Domains: Allow holes in genpd_data.domains array
  PM / Domains: Add support for removing nested PM domains by provider
  PM / Domains: Add support for removing PM domains
  PM / Domains: Store the provider in the PM domain structure
  PM / Domains: Prepare for adding support to remove PM domains
  PM / Domains: Verify the PM domain is present when adding a provider
  PM / Domains: Don't expose xlate and provider helper functions
  PM / Domains: Don't expose generic_pm_domain structure to clients
  staging: board: Remove calls to of_genpd_get_from_provider()
  ARM: EXYNOS: Remove calls to of_genpd_get_from_provider()
  PM / Domains: Add new helper functions for device-tree
  PM / Domains: Always enable debugfs support if available

* device-properties:
  serial: 8250_dw: Add quirk for APM X-Gene SoC
  ACPI / LPSS: Provide build-in properties of the UART
  ACPI / APD: Provide build-in properties of the UART
  driver core: Don't leak secondary fwnode on device removal