Merge tag 'pwm/for-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This contains mostly minor bug fixes as well as some new chip support
  for existing drivers"

* tag 'pwm/for-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: mediatek: Add MT7628 support
  dt-bindings: pwm: Add MT7628 information
  dt-bindings: pwm: rcar: Add bindings for R-Car E3 support
  pwm: meson: Fix mux clock names
  pwm: stm32-lp: Remove useless loop in stm32_pwm_lp_remove()
  pwm: omap-dmtimer: Return -EPROBE_DEFER if no dmtimer platform data
  pwm: mxs: Switch to SPDX identifier
  dt-bindings: pwm: fsl-ftm: Add compatible string for i.MX8QM
  pwm: fsl-ftm: Enable support for the new SoC i.MX8QM
  pwm: fsl-ftm: Added the support of per-compatible data
  pwm: fsl-ftm: Added a dedicated IP interface clock
  pwm: cros-ec: Switch to SPDX identifier
  pwm: imx: Switch to SPDX identifier
  pwm: tiehrpwm: Fix disabling of output of PWMs
  pwm: tiehrpwm: Don't use emulation mode bits to control PWM output
  pwm: berlin: Don't use broken prescaler values

Pull fbdev updates from Bartlomiej Zolnierkiewicz:
 "Mostly small fixes and cleanups for fb drivers (the biggest updates
  are for udlfb and pxafb drivers). This also adds deferred console
  takeover support to the console code and efifb driver.

  Summary:

   - add support for deferred console takeover, when enabled defers
     fbcon taking over the console from the dummy console until the
     first text is displayed on the console - together with the "quiet"
     kernel commandline option this allows fbcon to still be used
     together with a smooth graphical bootup (Hans de Goede)

   - improve console locking debugging code (Thomas Zimmermann)

   - copy the ACPI BGRT boot graphics to the framebuffer when deferred
     console takeover support is used in efifb driver (Hans de Goede)

   - update udlfb driver - fix lost console when the user unplugs a USB
     adapter, fix the screen corruption issue, fix locking and add some
     performance optimizations (Mikulas Patocka)

   - update pxafb driver - fix using uninitialized memory, switch to
     devm_* API, handle initialization errors and add support for
     lcd-supply regulator (Daniel Mack)

   - add support for boards booted with a DeviceTree in pxa3xx_gcu
     driver (Daniel Mack)

   - rename omap2 module to omap2fb.ko to avoid conflicts with omap1
     driver (Arnd Bergmann)

   - enable ACPI-based enumeration for goldfishfb driver (Yu Ning)

   - fix goldfishfb driver to make user space Android code use 60 fps
     (Christoffer Dall)

   - print big fat warning when nomodeset kernel parameter is used in
     vgacon driver (Lyude Paul)

   - remove VLA usage from fsl-diu-fb driver (Kees Cook)

   - misc fixes (Julia Lawall, Geert Uytterhoeven, Fredrik Noring,
     Yisheng Xie, Dan Carpenter, Daniel Vetter, Anton Vasilyev, Randy
     Dunlap, Gustavo A. R. Silva, Colin Ian King, Fengguang Wu)

   - misc cleanups (Roman Kiryanov, Yisheng Xie, Colin Ian King)"

* tag 'fbdev-v4.19' of https://github.com/bzolnier/linux: (54 commits)
  Documentation/fb: corrections for fbcon.txt
  fbcon: Do not takeover the console from atomic context
  dummycon: Stop exporting dummycon_[un]register_output_notifier
  fbcon: Only defer console takeover if the current console driver is the dummycon
  fbcon: Only allow FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER if fbdev is builtin
  fbdev: omap2: omapfb: fix ifnullfree.cocci warnings
  fbdev: omap2: omapfb: fix bugon.cocci warnings
  fbdev: omap2: omapfb: fix boolreturn.cocci warnings
  fb: amifb: fix build warnings when not builtin
  fbdev/core: Disable console-lock warnings when fb.lockless_register_fb is set
  console: Replace #if 0 with atomic var 'ignore_console_lock_warning'
  udlfb: use spin_lock_irq instead of spin_lock_irqsave
  udlfb: avoid prefetch
  udlfb: optimization - test the backing buffer
  udlfb: allow reallocating the framebuffer
  udlfb: set line_length in dlfb_ops_set_par
  udlfb: handle allocation failure
  udlfb: set optimal write delay
  udlfb: make a local copy of fb_ops
  udlfb: don't switch if we are switching to the same videomode
  ...

Pull sound fixes from Takashi Iwai:
 "No surprises here: a regression fix for virmidi code refactoring,
  three fixes for the new AC97 bus compat and runtime PM, and a usual
  HD-audio quirk"

* tag 'sound-fix-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda/realtek - Fix HP Headset Mic can't record
  ALSA: ac97: fix unbalanced pm_runtime_enable
  ALSA: ac97: fix check of pm_runtime_get_sync failure
  ALSA: ac97: fix device initialization in the compat layer
  ALSA: seq: virmidi: Fix discarding the unsubscribed output

Pull more rdma updates from Jason Gunthorpe:
 "This is the SMC cleanup promised, a randconfig regression fix, and
  kernel oops fix.

  Summary:

   - Switch SMC over to rdma_get_gid_attr and remove the compat

   - Fix a crash in HFI1 with some BIOS's

   - Fix a randconfig failure"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  IB/ucm: fix UCM link error
  IB/hfi1: Invalid NUMA node information can cause a divide by zero
  RDMA/smc: Replace ib_query_gid with rdma_get_gid_attr

Merge fixes for missing TLB shootdowns.

This fixes a couple of cases that involved us possibly freeing page
table structures before the required TLB shootdown had been done.

There are a few cleanup patches to make the code easier to follow, and
to avoid some of the more problematic cases entirely when not necessary.

To make this easier for backports, it undoes the recent lazy TLB
patches, because the cleanups and fixes are more important, and Rik is
ok with re-doing them later when things have calmed down.

The missing TLB flush was only delayed, and the wrong ordering only
happened under memory pressure (and in theory under a couple of other
fairly theoretical situations), so this may have been all very unlikely
to have hit people in practice.

But getting the TLB shootdown wrong is _so_ hard to debug and see that I
consider this a crticial fix.

Many thanks to Jann Horn for having debugged this.

* tlb-fixes:
  x86/mm: Only use tlb_remove_table() for paravirt
  mm: mmu_notifier fix for tlb_end_vma
  mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE
  mm/tlb: Remove tlb_remove_table() non-concurrent condition
  mm: move tlb_table_flush to tlb_flush_mmu_free
  x86/mm/tlb: Revert the recent lazy TLB patches

Pull xen fixes and cleanups from Juergen Gross:
 "Some cleanups, some minor fixes and a fix for a bug introduced in this
  merge window hitting 32-bit PV guests"

* tag 'for-linus-4.19b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: enable early use of set_fixmap in 32-bit Xen PV guest
  xen: remove unused hypercall functions
  x86/xen: remove unused function xen_auto_xlated_memory_setup()
  xen/ACPI: don't upload Px/Cx data for disabled processors
  x86/Xen: further refine add_preferred_console() invocations
  xen/mcelog: eliminate redundant setting of interface version
  x86/Xen: mark xen_setup_gdt() __init

Pull MIPS fixes from Paul Burton:

  - Fix microMIPS build failures by adding a .insn directive to the
    barrier_before_unreachable() asm statement in order to convince the
    toolchain that the asm statement is a valid branch target rather
    than a bogus attempt to switch ISA.

  - Clean up our declarations of TLB functions that we overwrite with
    generated code in order to prevent the compiler making assumptions
    about alignment that cause microMIPS kernels built with GCC 7 &
    above to die early during boot.

  - Fix up a regression for MIPS32 kernels which slipped into the main
    MIPS pull for 4.19, causing CONFIG_32BIT=y kernels to contain
    inappropriate MIPS64 instructions.

  - Extend our existing workaround for MIPSr6 builds that end up using
    the __multi3 intrinsic to GCC 7 & below, rather than just GCC 7.

* tag 'mips_4.19_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: lib: Provide MIPS64r6 __multi3() for GCC < 7
  MIPS: Workaround GCC __builtin_unreachable reordering bug
  compiler.h: Allow arch-specific asm/compiler.h
  MIPS: Avoid move psuedo-instruction whilst using MIPS_ISA_LEVEL
  MIPS: Consistently declare TLB functions
  MIPS: Export tlbmiss_handler_setup_pgd near its definition

Pull OpenRISC update from Stafford Horne:
 "Just one change for 4.19: refactoring from Christoph Hellwig to use
  generic DMA facilities"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: use generic dma_noncoherent_ops
  openrisc: fix cache maintainance the the sync_single_for_device DMA operation
  openrisc: remove the no-op unmap_page and unmap_sg DMA operations
  openrisc: remove the sync_single_for_cpu DMA operation

Pull ARM device-tree updates from Olof Johansson:
 "Business as usual -- the bulk of our changes are to devicetree files
  with new hardware support, new SoCs and platforms, and new board
  types.

  New SoCs/platforms:
   - Raspberry Pi Compute Module (CM1) and IO board
   - i.MX6SSL from NXP
   - Renesas RZ/N1D SoC (R9A06G032), Dual Cortex-A7 with Ethernet, CAN
     and PLC interfaces
   - TI AM654 SoC, Quad Cortex-A53, safety subsystem with Cortex-R5
     controllers, communication and PRU subsystem and lots of other
     interfaces (PCIe, USB3, etc).

  New boards and systems:
   - Several Atmel at91-based boards from Laird
   - Marvell Armada388-based Helios4 board from SolidRun
   - Samsung Aires-based phones (s5pv210)
   - Allwinner A64-based Pinebook laptop

  In addition to the above, there's the usual amount of new devices
  described on existing platforms, fixes and tweaks and new minor
  variants of boards/platforms"

* tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (478 commits)
  arm64: dts: sdm845: Add tsens nodes
  arm64: dts: msm8996: thermal: Initialise via DT and add second controller
  arm64: dts: sprd: Add one suspend timer
  arm64: dts: sprd: Add SC27XX ADC device
  arm64: dts: sprd: Add SC27XX eFuse device
  arm64: dts: sprd: Add SC27XX vibrator device
  arm64: dts: sprd: Add SC27XX breathing light controller device
  arm64: dts: meson-axg: add spdif-dit codec
  arm64: dts: meson-axg: add lineout codec
  arm64: dts: meson-axg: add linein codec
  arm64: dts: meson-axg: add tdm interfaces
  arm64: dts: meson-axg: add tdmout formatters
  arm64: dts: meson-axg: add tdmin formatters
  arm64: dts: meson-axg: add spdifout
  arm64: dts: rockchip: add led support for Firefly-RK3399
  arm64: dts: rockchip: remove deprecated Type-C PHY properties on rk3399
  arm64: dts: rockchip: add power button support for Firefly-RK3399
  ARM: dts: aspeed: Add coprocessor interrupt controller
  arm64: dts: meson-axg: add audio arb reset controller
  arm64: dts: meson-axg: add usb power regulator
  ...

Pull ARM SoC defconfig updates from Olof Johansson:
 "We keep these separate since some files are shared and conflict-prone,
  but there isn't really much to write about here.

  Some of the churnier pieces is for the Aspeed platforms, which did an
  overdue refresh of the defconfig, and enabled USB gadget and some
  drivers from there. Most of the rest are minor additions here and
  there to turn on drivers that are needed or useful on the various
  platforms"

* tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (39 commits)
  ARM: multi_v7_defconfig: add CONFIG_UNIPHIER_THERMAL and CONFIG_SNI_AVE
  ARM: config: aspeed: Enable new FSI drivers
  ARM: config: multi_v5: Enable ASPEED drivers
  ARM: config: multi_v5: Refresh configuration
  ARM: config: aspeed: Update defconfig
  ARM: multi_v7_defconfig: Enable support for RZN1D-DB
  ARM: shmobile: defconfig: Disable /sbin/hotplug fork-bomb
  ARM: shmobile: defconfig: Enable support for RZN1D-DB
  ARM: shmobile: defconfig: Enable reset controller support
  ARM: shmobile: defconfig: Drop NET_VENDOR_<FOO>=n
  arm64: defconfig: Enable more peripherals for Samsung Chromebook Plus.
  arm64: defconfig: Enable CONFIG_MTD_NAND_QCOM for IPQ8074
  ARM: qcom_defconfig: Enable QCOM NAND related configs
  ARM: imx_v6_v7_defconfig: add DMATEST support
  ARM: mvebu_v7_defconfig: enable SFP support
  ARM: mvebu_v7_defconfig: sync defconfig
  ARM: multi_v7_defconfig: Add Marvell NAND controller support
  arm: configs: Add USB gadget to Aspeed G5 defconfig
  arm: configs: Add USB gadget to Aspeed G4 defconfig
  arm64: defconfig: enable HiSilicon PMU driver
  ...

Pull ARM SoC driver updates from Olof Johansson:
 "Some of the larger changes this merge window:

   - Removal of drivers for Exynos5440, a Samsung SoC that never saw
     widespread use.

   - Uniphier support for USB3 and SPI reset handling

   - Syste control and SRAM drivers and bindings for Allwinner platforms

   - Qualcomm AOSS (Always-on subsystem) reset controller drivers

   - Raspberry Pi hwmon driver for voltage

   - Mediatek pwrap (pmic) support for MT6797 SoC"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (52 commits)
  drivers/firmware: psci_checker: stash and use topology_core_cpumask for hotplug tests
  soc: fsl: cleanup Kconfig menu
  soc: fsl: dpio: Convert DPIO documentation to .rst
  staging: fsl-mc: Remove remaining files
  staging: fsl-mc: Move DPIO from staging to drivers/soc/fsl
  staging: fsl-dpaa2: eth: move generic FD defines to DPIO
  soc: fsl: qe: gpio: Add qe_gpio_set_multiple
  usb: host: exynos: Remove support for Exynos5440
  clk: samsung: Remove support for Exynos5440
  soc: sunxi: Add the A13, A23 and H3 system control compatibles
  reset: uniphier: add reset control support for SPI
  cpufreq: exynos: Remove support for Exynos5440
  ata: ahci-platform: Remove support for Exynos5440
  soc: imx6qp: Use GENPD_FLAG_ALWAYS_ON for PU errata
  soc: mediatek: pwrap: add mt6351 driver for mt6797 SoCs
  soc: mediatek: pwrap: add pwrap driver for mt6797 SoCs
  soc: mediatek: pwrap: fix cipher init setting error
  dt-bindings: pwrap: mediatek: add pwrap support for MT6797
  reset: uniphier: add USB3 core reset control
  dt-bindings: reset: uniphier: add USB3 core reset support
  ...

Pull ARM 32-bit SoC platform updates from Olof Johansson:
 "Most of the SoC updates in this cycle are cleanups and moves to more
  modern infrastructure:

   - Davinci was moved to common clock framework

   - OMAP1-based Amstrad E3 "Superphone" saw a bunch of cleanups to the
     keyboard interface (bitbanged AT keyboard via GPIO).

   - Removal of some stale code for Renesas platforms

   - Power management improvements for i.MX6LL"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (112 commits)
  ARM: uniphier: select RESET_CONTROLLER
  arm64: uniphier: select RESET_CONTROLLER
  ARM: uniphier: remove empty Makefile
  ARM: exynos: Clear global variable on init error path
  ARM: exynos: Remove outdated maintainer information
  ARM: shmobile: Always enable ARCH_TIMER on SoCs with A7 and/or A15
  ARM: shmobile: r8a7779: hide unused r8a7779_platform_cpu_kill
  soc: r9a06g032: don't build SMP files for non-SMP config
  ARM: shmobile: Add the R9A06G032 SMP enabler driver
  ARM: at91: pm: configure wakeup sources for ULP1 mode
  ARM: at91: pm: add PMC fast startup registers defines
  ARM: at91: pm: Add ULP1 mode support
  ARM: at91: pm: Use ULP0 naming instead of slow clock
  ARM: hisi: handle of_iomap and fix missing of_node_put
  ARM: hisi: check of_iomap and fix missing of_node_put
  ARM: hisi: fix error handling and missing of_node_put
  ARM: mx5: Set the DBGEN bit in ARM_GPC register
  ARM: imx51: Configure M4IF to avoid visual artifacts
  ARM: imx: call imx6sx_cpuidle_init() conditionally for 6sll
  ARM: imx: fix i.MX6SLL build
  ...

Merge tag 'riscv-for-linus-4.19-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V fixes from Palmer Dabbelt:
 "This contains a pair of fixes to the RISC-V port:

   - The removal of our compat.h, which didn't do anything.

   - Fixes to sys_riscv_flush_icache to ensure it actually shows up.

     We're going to just call this a bug in the ABI, as it was always
     supposed to be there.

  I've given these a simple build+boot test, both individually and as
  the actual tag"

* tag 'riscv-for-linus-4.19-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  riscv: Delete asm/compat.h
  RISC-V: Don't use a global include guard for uapi/asm/syscalls.h
  RISC-V: Define sys_riscv_flush_icache when SMP=n

Pull tracing fixes from Steven Rostedt:
 "Masami found an off by one bug in the code that keeps "notrace"
  functions from being traced by kprobes. During my testing, I found
  that there's places that we may want to add kprobes to notrace, thus
  we may end up changing this code before 4.19 is released.

  The history behind this change is that we found that adding kprobes to
  various notrace functions caused the kernel to crashed. We took the
  safe route and decided not to allow kprobes to trace any notrace
  function.

  But because notrace is added to functions that just cause weird side
  effects to the function tracer, but are still safe, preventing kprobes
  for all notrace functios may be too much of a big hammer.

  One such place is __schedule() is marked notrace, to keep function
  tracer from doing strange recursive loops when it gets traced with
  NEED_RESCHED set. With this change, one can not add kprobes to the
  scheduler.

  Masami also added code to use gcov on ftrace"

* tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Fix to check notrace function with correct range
  tracing: Allow gcov profiling on only ftrace subsystem

If we don't use paravirt; don't play unnecessary and complicated games
to free page-tables.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The generic tlb_end_vma does not call invalidate_range mmu notifier, and
it resets resets the mmu_gather range, which means the notifier won't be
called on part of the range in case of an unmap that spans multiple
vmas.

ARM64 seems to be the only arch I could see that has notifiers and uses
the generic tlb_end_vma.  I have not actually tested it.

[ Catalin and Will point out that ARM64 currently only uses the
  notifiers for KVM, which doesn't use the ->invalidate_range()
  callback right now, so it's a bug, but one that happens to
  not affect them.  So not necessary for stable.  - Linus ]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Jann reported that x86 was missing required TLB invalidates when he
hit the !*batch slow path in tlb_remove_table().

This is indeed the case; RCU_TABLE_FREE does not provide TLB (cache)
invalidates, the PowerPC-hash where this code originated and the
Sparc-hash where this was subsequently used did not need that. ARM
which later used this put an explicit TLB invalidate in their
__p*_free_tlb() functions, and PowerPC-radix followed that example.

But when we hooked up x86 we failed to consider this. Fix this by
(optionally) hooking tlb_remove_table() into the TLB invalidate code.

NOTE: s390 was also needing something like this and might now
      be able to use the generic code again.

[ Modified to be on top of Nick's cleanups, which simplified this patch
  now that tlb_flush_mmu_tlbonly() really only flushes the TLB - Linus ]

Fixes: 9e52fc2b ("x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Will noted that only checking mm_users is incorrect; we should also
check mm_count in order to cover CPUs that have a lazy reference to
this mm (and could do speculative TLB operations).

If removing this turns out to be a performance issue, we can
re-instate a more complete check, but in tlb_table_flush() eliding the
call_rcu_sched().

Fixes: 26723911 ("mm, powerpc: move the RCU page-table freeing into generic code")
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There is no need to call this from tlb_flush_mmu_tlbonly, it logically
belongs with tlb_flush_mmu_free.  This makes future fixes simpler.

[ This was originally done to allow code consolidation for the
  mmu_notifier fix, but it also ends up helping simplify the
  HAVE_RCU_TABLE_INVALIDATE fix.    - Linus ]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Revert commits:

  95b0e635 x86/mm/tlb: Always use lazy TLB mode
  64482aaf x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs
  ac031589 x86/mm/tlb: Make lazy TLB mode lazier
  61d0beb5 x86/mm/tlb: Restructure switch_mm_irqs_off()
  2ff6ddf1 x86/mm/tlb: Leave lazy TLB mode at page table free time

In order to simplify the TLB invalidate fixes for x86 and unify the
parts that need backporting.  We'll try again later.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit cafa0010 ("Raise the minimum required gcc version to 4.6")
recently exposed a brittle part of the build for supporting non-gcc
compilers.

Both Clang and ICC define __GNUC__, __GNUC_MINOR__, and
__GNUC_PATCHLEVEL__ for quick compatibility with code bases that haven't
added compiler specific checks for __clang__ or __INTEL_COMPILER.

This is brittle, as they happened to get compatibility by posing as a
certain version of GCC.  This broke when upgrading the minimal version
of GCC required to build the kernel, to a version above what ICC and
Clang claim to be.

Rather than always including compiler-gcc.h then undefining or
redefining macros in compiler-intel.h or compiler-clang.h, let's
separate out the compiler specific macro definitions into mutually
exclusive headers, do more proper compiler detection, and keep shared
definitions in compiler_types.h.

Fixes: cafa0010 ("Raise the minimum required gcc version to 4.6")
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Eli Friedman <efriedma@codeaurora.org>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull x86 platform driver updates from Andy Shevchenko:

 - The driver for Silead touchscreen configurations has been renamed
   from silead_dmi to touchscreen_dmi since it starts supporting other
   touchscreens which require some DMI quirks

   It also gets expanded to cover cases for Chuwi Vi10, ONDA V891W,
   Connect Tablet 9, Onda V820w, and Cube KNote i1101 tablets.

 - Another bunch of changes is related to Mellanox platform code to
   allow user space to communicate with Mellanox for system control and
   monitoring purposes. The driver notifies user on hotplug device
   signal receiving.

 - ASUS WMI drivers recognize lid flip action on UX360, and correctly
   toggles airplane mode LED. In addition the keyboard backlight toggle
   gets support.

 - ThinkPad ACPI driver enables support for calculator key (on at least
   P52). It also has been fixed to support three characters model
   designators, which are used for modern laptops. Earlier the battery,
   marked as BAT1, on ThinkPad laptops has not been configured properly,
   which is fixed. On the opposite the multi-battery configurations now
   probed correctly.

 - Dell SMBIOS driver starts working on some Dell servers which do not
   support token interface. The regression with backlight detection has
   also been fixed. In order to support dock mode on some laptops, Intel
   virtual button driver has been fixed. The last but not least is the
   fix to Intel HID driver due to changes in Dell systems that prevented
   to use power button.

* tag 'platform-drivers-x86-v4.19-1' of git://git.infradead.org/linux-platform-drivers-x86: (47 commits)
  platform/x86: acer-wmi: Silence "unsupported" message a bit
  platform/x86: intel_punit_ipc: fix build errors
  platform/x86: ideapad: Add Y520-15IKBM and Y720-15IKBM to no_hw_rfkill
  platform/x86: asus-nb-wmi: Add keymap entry for lid flip action on UX360
  platform/x86: acer-wmi: refactor function has_cap
  platform/x86: thinkpad_acpi: Fix multi-battery bug
  platform/x86: thinkpad_acpi: extend battery quirk coverage
  platform/x86: touchscreen_dmi: Add info for the Cube KNote i1101 tablet
  platform/x86: mlx-platform: Fix copy-paste error in mlxplat_init()
  platform/x86: mlx-platform: Remove unused define
  platform/x86: mlx-platform: Change mlxreg-io configuration for MSN274x systems
  Documentation/ABI: Add new attribute for mlxreg-io sysfs interfaces
  platform/x86: mlx-platform: Allow mlxreg-io driver activation for more systems
  platform/x86: mlx-platform: Add ASIC hotplug device configuration
  platform/mellanox: mlxreg-hotplug: Add hotplug hwmon uevent notification
  platform/mellanox: mlxreg-hotplug: Improve mechanism of ASIC health discovery
  platform/x86: mlx-platform: Add mlxreg-fan platform driver activation
  platform/x86: dell-laptop: Fix backlight detection
  platform/x86: toshiba_acpi: Fix defined but not used build warnings
  platform/x86: thinkpad_acpi: Support battery quirk
  ...

This has been broken for an embarassingly long time (since v4.4).

Just needs a couple of __init tags on functions to make the sections
match up.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more parisc updates from Helge Deller:

 - fix boot failure of 64-bit kernel. It got broken by the unwind
   optimization commit in merge window.

 - fix 64-bit userspace support (static 64-bit applications only, e.g.
   we don't yet have 64-bit userspace support in glibc).

 - consolidate unwind initialization code.

 - add machine model description to stack trace.

* 'parisc-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Add hardware description to stack traces
  parisc: Fix boot failure of 64-bit kernel
  parisc: Consolidate unwind initialization calls
  parisc: Update comments in syscall.S regarding wide userland
  parisc: Fix ptraced 64-bit applications to call 64-bit syscalls
  parisc: Restore possibility to execute 64-bit applications

Pull Xtensa updates from Max Filippov:

 - switch xtensa arch to the generic noncoherent direct mapping
   operations

 - add support for DMA_ATTR_NO_KERNEL_MAPPING attribute

 - clean up users of platform/hardware.h in generic Xtensa code

 - fix assembly cache maintenance code for long cache lines

 - rework noMMU cache attributes initialization

 - add big-endian HiFi2 test_kc705_be CPU variant

* tag 'xtensa-20180820' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: add test_kc705_be variant
  xtensa: clean up boot-elf/bootstrap.S
  xtensa: make bootparam parsing optional
  xtensa: drop variant IRQ support
  xtensa: drop unneeded platform/hardware.h headers
  xtensa: move PLATFORM_NR_IRQS to Kconfig
  xtensa: rework {CONFIG,PLATFORM}_DEFAULT_MEM_START
  xtensa: drop unused {CONFIG,PLATFORM}_DEFAULT_MEM_SIZE
  xtensa: rework noMMU cache attributes initialization
  xtensa: increase ranges in ___invalidate_{i,d}cache_all
  xtensa: limit offsets in __loop_cache_{all,page}
  xtensa: platform-specific handling of coherent memory
  xtensa: support DMA_ATTR_NO_KERNEL_MAPPING attribute
  xtensa: use generic dma_noncoherent_ops

Pull second set of KVM updates from Paolo Bonzini:
 "ARM:
   - Support for Group0 interrupts in guests
   - Cache management optimizations for ARMv8.4 systems
   - Userspace interface for RAS
   - Fault path optimization
   - Emulated physical timer fixes
   - Random cleanups

  x86:
   - fixes for L1TF
   - a new test case
   - non-support for SGX (inject the right exception in the guest)
   - fix lockdep false positive"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (49 commits)
  KVM: VMX: fixes for vmentry_l1d_flush module parameter
  kvm: selftest: add dirty logging test
  kvm: selftest: pass in extra memory when create vm
  kvm: selftest: include the tools headers
  kvm: selftest: unify the guest port macros
  tools: introduce test_and_clear_bit
  KVM: x86: SVM: Call x86_spec_ctrl_set_guest/host() with interrupts disabled
  KVM: vmx: Inject #UD for SGX ENCLS instruction in guest
  KVM: vmx: Add defines for SGX ENCLS exiting
  x86/kvm/vmx: Fix coding style in vmx_setup_l1d_flush()
  x86: kvm: avoid unused variable warning
  KVM: Documentation: rename the capability of KVM_CAP_ARM_SET_SERROR_ESR
  KVM: arm/arm64: Skip updating PTE entry if no change
  KVM: arm/arm64: Skip updating PMD entry if no change
  KVM: arm: Use true and false for boolean values
  KVM: arm/arm64: vgic: Do not use spin_lock_irqsave/restore with irq disabled
  KVM: arm/arm64: vgic: Move DEBUG_SPINLOCK_BUG_ON to vgic.h
  KVM: arm: vgic-v3: Add support for ICC_SGI0R and ICC_ASGI1R accesses
  KVM: arm64: vgic-v3: Add support for ICC_SGI0R_EL1 and ICC_ASGI1R_EL1 accesses
  KVM: arm/arm64: vgic-v3: Add core support for Group0 SGIs
  ...

Pull more block updates from Jens Axboe:

 - Set of bcache fixes and changes (Coly)

 - The flush warn fix (me)

 - Small series of BFQ fixes (Paolo)

 - wbt hang fix (Ming)

 - blktrace fix (Steven)

 - blk-mq hardware queue count update fix (Jianchao)

 - Various little fixes

* tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block: (31 commits)
  block/DAC960.c: make some arrays static const, shrinks object size
  blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter
  blk-mq: init hctx sched after update ctx and hctx mapping
  block: remove duplicate initialization
  tracing/blktrace: Fix to allow setting same value
  pktcdvd: fix setting of 'ret' error return for a few cases
  block: change return type to bool
  block, bfq: return nbytes and not zero from struct cftype .write() method
  block, bfq: improve code of bfq_bfqq_charge_time
  block, bfq: reduce write overcharge
  block, bfq: always update the budget of an entity when needed
  block, bfq: readd missing reset of parent-entity service
  blk-wbt: fix IO hang in wbt_wait()
  block: don't warn for flush on read-only device
  bcache: add the missing comments for smp_mb()/smp_wmb()
  bcache: remove unnecessary space before ioctl function pointer arguments
  bcache: add missing SPDX header
  bcache: move open brace at end of function definitions to next line
  bcache: add static const prefix to char * array declarations
  bcache: fix code comments style
  ...

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've tuned f2fs to improve general performance by
  serializing block allocation and enhancing discard flows like fstrim
  which avoids user IO contention. And we've added fsync_mode=nobarrier
  which gives an option to user where it skips issuing cache_flush
  commands to underlying flash storage. And there are many bug fixes
  related to fuzzed images, revoked atomic writes, quota ops, and minor
  direct IO.

  Enhancements:
   - add fsync_mode=nobarrier which bypasses cache_flush command
   - enhance the discarding flow which avoids user IOs and issues in
     LBA order
   - readahead some encrypted blocks during GC
   - enable in-memory inode checksum to verify the blocks if
     F2FS_CHECK_FS is set
   - enhance nat_bits behavior
   - set -o discard by default
   - set REQ_RAHEAD to bio in ->readpages

  Bug fixes:
   - fix a corner case to corrupt atomic_writes revoking flow
   - revisit i_gc_rwsem to fix race conditions
   - fix some dio behaviors captured by xfstests
   - correct handling errors given by quota-related failures
   - add many sanity check flows to avoid fuzz test failures
   - add more error number propagation to their callers
   - fix several corner cases to continue fault injection w/ shutdown
     loop"

* tag 'f2fs-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (89 commits)
  f2fs: readahead encrypted block during GC
  f2fs: avoid fi->i_gc_rwsem[WRITE] lock in f2fs_gc
  f2fs: fix performance issue observed with multi-thread sequential read
  f2fs: fix to skip verifying block address for non-regular inode
  f2fs: rework fault injection handling to avoid a warning
  f2fs: support fault_type mount option
  f2fs: fix to return success when trimming meta area
  f2fs: fix use-after-free of dicard command entry
  f2fs: support discard submission error injection
  f2fs: split discard command in prior to block layer
  f2fs: wake up gc thread immediately when gc_urgent is set
  f2fs: fix incorrect range->len in f2fs_trim_fs()
  f2fs: refresh recent accessed nat entry in lru list
  f2fs: fix avoid race between truncate and background GC
  f2fs: avoid race between zero_range and background GC
  f2fs: fix to do sanity check with block address in main area v2
  f2fs: fix to do sanity check with inline flags
  f2fs: fix to reset i_gc_failures correctly
  f2fs: fix invalid memory access
  f2fs: fix to avoid broken of dnode block list
  ...

...otherwise there will be list corruption due to inode_sb_list_add() being
called for inode already on the sb list.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: e950564b ("vfs: don't evict uninitialized inode")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge more updates from Andrew Morton:

 - the rest of MM

 - procfs updates

 - various misc things

 - more y2038 fixes

 - get_maintainer updates

 - lib/ updates

 - checkpatch updates

 - various epoll updates

 - autofs updates

 - hfsplus

 - some reiserfs work

 - fatfs updates

 - signal.c cleanups

 - ipc/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits)
  ipc/util.c: update return value of ipc_getref from int to bool
  ipc/util.c: further variable name cleanups
  ipc: simplify ipc initialization
  ipc: get rid of ids->tables_initialized hack
  lib/rhashtable: guarantee initial hashtable allocation
  lib/rhashtable: simplify bucket_table_alloc()
  ipc: drop ipc_lock()
  ipc/util.c: correct comment in ipc_obtain_object_check
  ipc: rename ipcctl_pre_down_nolock()
  ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid()
  ipc: reorganize initialization of kern_ipc_perm.seq
  ipc: compute kern_ipc_perm.id under the ipc lock
  init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
  fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp
  adfs: use timespec64 for time conversion
  kernel/sysctl.c: fix typos in comments
  drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md
  fork: don't copy inconsistent signal handler state to child
  signal: make get_signal() return bool
  signal: make sigkill_pending() return bool
  ...

ipc_getref has still a return value of type "int", matching the atomic_t
interface of atomic_inc_not_zero()/atomic_add_unless().

ipc_getref now uses refcount_inc_not_zero, which has a return value of
type "bool".

Therefore, update the return code to avoid implicit conversions.

Link: http://lkml.kernel.org/r/20180712185241.4017-13-manfred@colorfullife.comSigned-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The varable names got a mess, thus standardize them again:

id: user space id. Called semid, shmid, msgid if the type is known.
    Most functions use "id" already.
idx: "index" for the idr lookup
    Right now, some functions use lid, ipc_addid() already uses idx as
    the variable name.
seq: sequence number, to avoid quick collisions of the user space id
key: user space key, used for the rhash tree

Link: http://lkml.kernel.org/r/20180712185241.4017-12-manfred@colorfullife.comSigned-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that we know that rhashtable_init() will not fail, we can get rid of a
lot of the unnecessary cleanup paths when the call errored out.

[manfred@colorfullife.com: variable name added to util.h to resolve checkpatch warning]
Link: http://lkml.kernel.org/r/20180712185241.4017-11-manfred@colorfullife.comSigned-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In sysvipc we have an ids->tables_initialized regarding the rhashtable,
introduced in 0cfb6aee ("ipc: optimize semget/shmget/msgget for lots
of keys")

It's there, specifically, to prevent nil pointer dereferences, from using
an uninitialized api.  Considering how rhashtable_init() can fail
(probably due to ENOMEM, if anything), this made the overall ipc
initialization capable of failure as well.  That alone is ugly, but fine,
however I've spotted a few issues regarding the semantics of
tables_initialized (however unlikely they may be):

- There is inconsistency in what we return to userspace: ipc_addid()
  returns ENOSPC which is certainly _wrong_, while ipc_obtain_object_idr()
  returns EINVAL.

- After we started using rhashtables, ipc_findkey() can return nil upon
  !tables_initialized, but the caller expects nil for when the ipc
  structure isn't found, and can therefore call into ipcget() callbacks.

Now that rhashtable initialization cannot fail, we can properly get rid of
the hack altogether.

[manfred@colorfullife.com: commit id extended to 12 digits]
Link: http://lkml.kernel.org/r/20180712185241.4017-10-manfred@colorfullife.comSigned-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rhashtable_init() may fail due to -ENOMEM, thus making the entire api
unusable.  This patch removes this scenario, however unlikely.  In order
to guarantee memory allocation, this patch always ends up doing
GFP_KERNEL|__GFP_NOFAIL for both the tbl as well as
alloc_bucket_spinlocks().

Upon the first table allocation failure, we shrink the size to the
smallest value that makes sense and retry with __GFP_NOFAIL semantics.
With the defaults, this means that from 64 buckets, we retry with only 4.
Any later issues regarding performance due to collisions or larger table
resizing (when more memory becomes available) is the least of our
problems.

Link: http://lkml.kernel.org/r/20180712185241.4017-9-manfred@colorfullife.comSigned-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

As of ce91f6ee ("mm: kvmalloc does not fallback to vmalloc for
incompatible gfp flags") we can simplify the caller and trust kvzalloc()
to just do the right thing.  For the case of the GFP_ATOMIC context, we
can drop the __GFP_NORETRY flag for obvious reasons, and for the
__GFP_NOWARN case, however, it is changed such that the caller passes the
flag instead of making bucket_table_alloc() handle it.

This slightly changes the gfp flags passed on to nested_table_alloc() as
it will now also use GFP_ATOMIC | __GFP_NOWARN.  However, I consider this
a positive consequence as for the same reasons we want nowarn semantics in
bucket_table_alloc().

[manfred@colorfullife.com: commit id extended to 12 digits, line wraps updated]
Link: http://lkml.kernel.org/r/20180712185241.4017-8-manfred@colorfullife.comSigned-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/util.c contains multiple functions to get the ipc object pointer given
an id number.

There are two sets of function: One set verifies the sequence counter part
of the id number, other functions do not check the sequence counter.

The standard for function names in ipc/util.c is
- ..._check() functions verify the sequence counter
- ..._idr() functions do not verify the sequence counter

ipc_lock() is an exception: It does not verify the sequence counter value,
but this is not obvious from the function name.

Furthermore, shm.c is the only user of this helper.  Thus, we can simply
move the logic into shm_lock() and get rid of the function altogether.

[manfred@colorfullife.com: most of changelog]
Link: http://lkml.kernel.org/r/20180712185241.4017-7-manfred@colorfullife.comSigned-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The comment that explains ipc_obtain_object_check is wrong: The function
checks the sequence number, not the reference counter.

Note that checking the reference counter would be meaningless: The
reference counter is decreased without holding any locks, thus an object
with kern_ipc_perm.deleted=true may disappear at the end of the next rcu
grace period.

Link: http://lkml.kernel.org/r/20180712185241.4017-6-manfred@colorfullife.comSigned-off-by: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Both the comment and the name of ipcctl_pre_down_nolock() are misleading:
The function must be called while holdling the rw semaphore.

Therefore the patch renames the function to ipcctl_obtain_check(): This
name matches the other names used in util.c:

- "obtain" function look up a pointer in the idr, without
  acquiring the object lock.
- The caller is responsible for locking.
- _check means that the sequence number is checked.

Link: http://lkml.kernel.org/r/20180712185241.4017-5-manfred@colorfullife.comSigned-off-by: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc_addid() is impossible to use:
- for certain failures, the caller must not use ipc_rcu_putref(),
  because the reference counter is not yet initialized.
- for other failures, the caller must use ipc_rcu_putref(),
  because parallel operations could be ongoing already.

The patch cleans that up, by initializing the refcount early, and by
modifying all callers.

The issues is related to the finding of
syzbot+2827ef6b3385deb07eaf@syzkaller.appspotmail.com: syzbot found an
issue with reading kern_ipc_perm.seq, here both read and write to already
released memory could happen.

Link: http://lkml.kernel.org/r/20180712185241.4017-4-manfred@colorfullife.comSigned-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>