review.tizen.org Git - platform/kernel/linux-starfive.git/log

Merge tag 'powerpc-5.8-1' of git://git./linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

- Support for userspace to send requests directly to the on-chip GZIP
   accelerator on Power9.

- Rework of our lockless page table walking (__find_linux_pte()) to
   make it safe against parallel page table manipulations without
   relying on an IPI for serialisation.

- A series of fixes & enhancements to make our machine check handling
   more robust.

- Lots of plumbing to add support for "prefixed" (64-bit) instructions
   on Power10.

- Support for using huge pages for the linear mapping on 8xx (32-bit).

- Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound
   driver.

- Removal of some obsolete 40x platforms and associated cruft.

- Initial support for booting on Power10.

- Lots of other small features, cleanups & fixes.

Thanks to: Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Andrey Abramov, Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent
Abali, Cédric Le Goater, Chen Zhou, Christian Zigotzky, Christophe
JAILLET, Christophe Leroy, Dmitry Torokhov, Emmanuel Nicolet, Erhard F.,
Gautham R. Shenoy, Geoff Levand, George Spelvin, Greg Kurz, Gustavo A.
R. Silva, Gustavo Walbon, Haren Myneni, Hari Bathini, Joel Stanley,
Jordan Niethe, Kajol Jain, Kees Cook, Leonardo Bras, Madhavan
Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Michal
Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram Pai,
Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher
Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler,
Wolfram Sang, Xiongfeng Wang.

* tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (299 commits)
  powerpc/pseries: Make vio and ibmebus initcalls pseries specific
  cxl: Remove dead Kconfig options
  powerpc: Add POWER10 architected mode
  powerpc/dt_cpu_ftrs: Add MMA feature
  powerpc/dt_cpu_ftrs: Enable Prefixed Instructions
  powerpc/dt_cpu_ftrs: Advertise support for ISA v3.1 if selected
  powerpc: Add support for ISA v3.1
  powerpc: Add new HWCAP bits
  powerpc/64s: Don't set FSCR bits in INIT_THREAD
  powerpc/64s: Save FSCR to init_task.thread.fscr after feature init
  powerpc/64s: Don't let DT CPU features set FSCR_DSCR
  powerpc/64s: Don't init FSCR_DSCR in __init_FSCR()
  powerpc/32s: Fix another build failure with CONFIG_PPC_KUAP_DEBUG
  powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel
  powerpc/module_64: Simplify check for -mprofile-kernel ftrace relocations
  powerpc/module_64: Consolidate ftrace code
  powerpc/32: Disable KASAN with pages bigger than 16k
  powerpc/uaccess: Don't set KUEP by default on book3s/32
  powerpc/uaccess: Don't set KUAP by default on book3s/32
  powerpc/8xx: Reduce time spent in allow_user_access() and friends
  ...

Merge tag 'modules-for-v5.8' of git://git./linux/kernel/git/jeyu/linux

Pull module updates from Jessica Yu:

- Harden CONFIG_STRICT_MODULE_RWX by rejecting any module that has
   SHF_WRITE|SHF_EXECINSTR sections

- Remove and clean up nested #ifdefs, as it makes code hard to read

* tag 'modules-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Harden STRICT_MODULE_RWX
  module: break nested ARCH_HAS_STRICT_MODULE_RWX and STRICT_MODULE_RWX #ifdefs

Merge tag 'x86-mm-2020-06-05' of git://git./linux/kernel/git/tip/tip

Pull x86 mm updates from Ingo Molnar:
"Misc changes:

   - Unexport various PAT primitives

   - Unexport per-CPU tlbstate and uninline TLB helpers"

* tag 'x86-mm-2020-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/tlb/uv: Add a forward declaration for struct flush_tlb_info
  x86/cpu: Export native_write_cr4() only when CONFIG_LKTDM=m
  x86/tlb: Restrict access to tlbstate
  xen/privcmd: Remove unneeded asm/tlb.h include
  x86/tlb: Move PCID helpers where they are used
  x86/tlb: Uninline nmi_uaccess_okay()
  x86/tlb: Move cr4_set_bits_and_update_boot() to the usage site
  x86/tlb: Move paravirt_tlb_remove_table() to the usage site
  x86/tlb: Move __flush_tlb_all() out of line
  x86/tlb: Move flush_tlb_others() out of line
  x86/tlb: Move __flush_tlb_one_kernel() out of line
  x86/tlb: Move __flush_tlb_one_user() out of line
  x86/tlb: Move __flush_tlb_global() out of line
  x86/tlb: Move __flush_tlb() out of line
  x86/alternatives: Move temporary_mm helpers into C
  x86/cr4: Sanitize CR4.PCE update
  x86/cpu: Uninline CR4 accessors
  x86/tlb: Uninline __get_current_cr3_fast()
  x86/mm: Use pgprotval_t in protval_4k_2_large() and protval_large_2_4k()
  x86/mm: Unexport __cachemode2pte_tbl
  ...

Merge tag 'riscv-for-linus-5.8-mw0' of git://git./linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

- The remainder of the code necessary to support the Kendryte K210:

     * Support for building device trees into the kernel, as the K210
       doesn't have a bootloader that provides one

     * A K210 device tree and the associated defconfig update

     * Support for skipping PMP initialization on systems that trap on
       PMP accesses rather than treating them as WARL

- Support for KGDB

- Improvements to text patching

- Some cleanups to the SiFive L2 cache driver

* tag 'riscv-for-linus-5.8-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  soc: sifive: l2 cache: Mark l2_get_priv_group as static
  soc: sifive: l2 cache: Eliminate an unsigned zero compare warning
  riscv: Add support to determine no. of L2 cache way enabled
  riscv: cacheinfo: Implement cache_get_priv_group with a generic ops structure
  riscv: Use text_mutex instead of patch_lock
  riscv: Use NOKPROBE_SYMBOL() instead of __krpobes annotation
  riscv: Remove the 'riscv_' prefix of function name
  riscv: Add SW single-step support for KDB
  riscv: Use the XML target descriptions to report 3 system registers
  riscv: Add KGDB support
  kgdb: Add kgdb_has_hit_break function
  RISC-V: Skip setting up PMPs on traps
  riscv: K210: Update defconfig
  riscv: K210: Add a built-in device tree
  riscv: Allow device trees to be built into the kernel

Merge tag 'devicetree-for-5.8' of git://git./linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:

- Convert various DT (non-binding) doc files to ReST

- Various improvements to device link code

- Fix __of_attach_node_sysfs refcounting bug

- Add support for 'memory-region-names' with reserved-memory binding

- Vendor prefixes for Protonic Holland, BeagleBoard.org, Alps, Check
   Point, Würth Elektronik, U-Boot, Vaisala, Baikal Electronics,
   Shanghai Awinic Technology Co., MikroTik, Silex Insight

- A bunch more binding conversions to DT schema. Only 3K to go.

- Add a minimum version check for schema tools

- Treewide dropping of 'allOf' usage with schema references. Not needed
   in new json-schema spec.

- Some formatting clean-ups of schemas

* tag 'devicetree-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (194 commits)
  dt-bindings: clock: Add documentation for X1830 bindings.
  dt-bindings: mailbox: Convert imx mu to json-schema
  dt-bindings: power: Convert imx gpcv2 to json-schema
  dt-bindings: power: Convert imx gpc to json-schema
  dt-bindings: Merge gpio-usb-b-connector with usb-connector
  dt-bindings: timer: renesas: cmt: Convert to json-schema
  dt-bindings: clock: Convert i.MX8QXP LPCG to json-schema
  dt-bindings: timer: Convert i.MX GPT to json-schema
  dt-bindings: thermal: rcar-thermal: Add device tree support for r8a7742
  dt-bindings: serial: Add binding for UART pin swap
  dt-bindings: geni-se: Add interconnect binding for GENI QUP
  dt-bindings: geni-se: Convert QUP geni-se bindings to YAML
  dt-bindings: vendor-prefixes: Add Silex Insight vendor prefix
  dt-bindings: input: touchscreen: edt-ft5x06: change reg property
  dt-bindings: usb: qcom,dwc3: Introduce interconnect properties for Qualcomm DWC3 driver
  dt-bindings: timer: renesas: mtu2: Convert to json-schema
  of/fdt: Remove redundant kbasename function call
  dt-bindings: clock: Convert i.MX1 clock to json-schema
  dt-bindings: clock: Convert i.MX21 clock to json-schema
  dt-bindings: clock: Convert i.MX25 clock to json-schema
  ...

Merge tag 'arm-dt-5.8' of git://git./linux/kernel/git/soc/soc

Pull ARM devicetree updates from Arnd Bergmann:
"This is the set of device tree changes, mostly covering new hardware
  support, with 577 patches touching a little over 500 files.

  There are five new Arm SoCs supported in this release, all of them for
  existing SoC families:

   - Realtek RTD1195, RTD1395 and RTD1619 -- three SoCs used in both NAS
     devices and Android Set-top-box designs, along with the
     "Horseradish", "Lion Skin" and "Mjolnir" reference platforms; the
     Mele X1000 and Xnano X5 set-top-boxes and the Banana Pi BPi-M4
     single-board computer.

   - Renesas RZ/G1H (r8a7742) -- a high-end 32-bit industrial SoC and
     the iW-RainboW-G21D-Qseven-RZG1H board/SoM

   - Rockchips RK3326 -- low-end 64-bit SoC along with the Odroid-GO
     Advance game console

  Newly added machines on already supported SoCs are:

   - AMLogic S905D based Smartlabs SML-5442TW TV box

   - AMLogic S905X3 based ODROID-C4 SBC

   - AMLogic S922XH based Beelink GT-King Pro TV box

   - Allwinner A20 based Olimex A20-OLinuXino-LIME-eMMC SBC

   - Aspeed ast2500 based BMCs in Facebook x86 "Yosemite V2" and YADRO
     OpenPower P9 "Nicole"

   - Marvell Kirkwood based Check Point L-50 router

   - Mediatek MT8173 based Elm/Hana Chromebook laptops

   - Microchip SAMA5D2 "Industrial Connectivity Platform" reference
     board

   - NXP i.MX8m based Beacon i.MX8m-Mini SoM development kit

   - Octavo OSDMP15x based Linux Automation MC-1 development board

   - Qualcomm SDM630 based Xiaomi Redmi Note 7 phone

   - Realtek RTD1295 based Xnano X5 TV Box

   - STMicroelectronics STM32MP1 based Stinger96 single-board computer
     and IoT Box

   - Samsung Exynos4210 based based Samsung Galaxy S2 phone

   - Socionext Uniphier based Akebi96 SBC

   - TI Keystone based K2G Evaluation board

   - TI am5729 based Beaglebone-AI development board

  Include device descriptions for additional hardware support in
  existing SoCs and machines based on all major SoC platforms:

   - AMlogic Meson

   - Allwinner sunxi

   - Arm Juno/VFP/Vexpress/Integrator

   - Broadcom bcm283x/bcm2711

   - Hisilicon hi6220

   - Marvell EBU

   - Mediatek MT27xx, MT76xx, MT81xx and MT67xx

   - Microchip SAMA5D2

   - NXP i.MX6/i.MX7/i.MX8 and Layerscape

   - Nvidia Tegra

   - Qualcomm Snapdragon

   - Renesas r8a77961, r8a7791

   - Rockchips RK32xx/RK33xx

   - ST-Ericsson ux500

   - STMicroelectronics SMT32

   - Samsung Exynos and S5PV210

   - Socionext Uniphier

   - TI OMAP5/DRA7 and Keystone"

* tag 'arm-dt-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (564 commits)
  ARM: dts: keystone: Rename "msmram" node to "sram"
  arm: dts: mt2712: add uart APDMA to device tree
  arm64: dts: mt8183: add mmc node
  arm64: dts: mt2712: add ethernet device node
  arm64: tegra: Make the RTC a wakeup source on Jetson Nano and TX1
  ARM: dts: mmp3: Add the fifth SD HCI
  ARM: dts: berlin*: Fix up the SDHCI node names
  ARM: dts: mmp3: Fix USB & USB PHY node names
  ARM: dts: mmp3: Fix L2 cache controller node name
  ARM: dts: mmp*: Fix up encoding of the /rtc interrupts property
  ARM: dts: pxa*: Fix up encoding of the /rtc interrupts property
  ARM: dts: pxa910: Fix the gpio interrupt cell number
  ARM: dts: pxa3xx: Fix up encoding of the /gpio interrupts property
  ARM: dts: pxa168: Fix the gpio interrupt cell number
  ARM: dts: pxa168: Add missing address/size cells to i2c nodes
  ARM: dts: dove: Fix interrupt controller node name
  ARM: dts: kirkwood: Fix interrupt controller node name
  arm64: dts: Add SC9863A emmc and sd card nodes
  arm64: dts: Add SC9863A clock nodes
  arm64: dts: mt6358: add PMIC MT6358 related nodes
  ...

Merge tag 'arm-drivers-5.8' of git://git./linux/kernel/git/soc/soc

Pull ARM/SoC driver updates from Arnd Bergmann:
"These are updates to SoC specific drivers that did not have another
  subsystem maintainer tree to go through for some reason:

   - Some bus and memory drivers for the MIPS P5600 based Baikal-T1 SoC
     that is getting added through the MIPS tree.

   - There are new soc_device identification drivers for TI K3, Qualcomm
     MSM8939

   - New reset controller drivers for NXP i.MX8MP, Renesas RZ/G1H, and
     Hisilicon hi6220

   - The SCMI firmware interface can now work across ARM SMC/HVC as a
     transport.

   - Mediatek platforms now use a new driver for their "MMSYS" hardware
     block that controls clocks and some other aspects in behalf of the
     media and gpu drivers.

   - Some Tegra processors have improved power management support,
     including getting woken up by the PMIC and cluster power down
     during idle.

   - A new v4l staging driver for Tegra is added.

   - Cleanups and minor bugfixes for TI, NXP, Hisilicon, Mediatek, and
     Tegra"

* tag 'arm-drivers-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (155 commits)
  clk: sprd: fix compile-testing
  bus: bt1-axi: Build the driver into the kernel
  bus: bt1-apb: Build the driver into the kernel
  bus: bt1-axi: Use sysfs_streq instead of strncmp
  bus: bt1-axi: Optimize the return points in the driver
  bus: bt1-apb: Use sysfs_streq instead of strncmp
  bus: bt1-apb: Use PTR_ERR_OR_ZERO to return from request-regs method
  bus: bt1-apb: Fix show/store callback identations
  bus: bt1-apb: Include linux/io.h
  dt-bindings: memory: Add Baikal-T1 L2-cache Control Block binding
  memory: Add Baikal-T1 L2-cache Control Block driver
  bus: Add Baikal-T1 APB-bus driver
  bus: Add Baikal-T1 AXI-bus driver
  dt-bindings: bus: Add Baikal-T1 APB-bus binding
  dt-bindings: bus: Add Baikal-T1 AXI-bus binding
  staging: tegra-video: fix V4L2 dependency
  tee: fix crypto select
  drivers: soc: ti: knav_qmss_queue: Make knav_gp_range_ops static
  soc: ti: add k3 platforms chipid module driver
  dt-bindings: soc: ti: add binding for k3 platforms chipid module
  ...

Merge tag 'arm-defconfig-5.8' of git://git./linux/kernel/git/soc/soc

Pull ARM defconfig updates from Arnd Bergmann:
"These are the usual updates to arm/arm64 defconfig files, enabling
  newly added drivers and addressing changes to Kconfig files"

* tag 'arm-defconfig-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (22 commits)
  ARM: imx_v6_v7_defconfig: extend RN5T618 PMIC family support
  arm64: defconfig: enable Qualcomm IPA and RMNet modules
  arm64: defconfig: Add LEDS_TRIGGER_TIMER
  arm64: defconfig: Enable UACCE/PCI PASID/SEC2/HPRE configs
  arm64: defconfig: Enable Qualcomm SC7180 pinctrl and gcc
  arm64: defconfig: Remove QCOM_GLINK_SSR
  ARM: multi_v7_defconfig: Enable r8a7742 SoC
  ARM: shmobile: defconfig: Enable r8a7742 SoC
  arm64: defconfig: enable meson gx audio as module
  arm64: defconfig: Enable SM8250 GCC driver
  ARM: defconfig: u8500: Enable new drivers for ux500
  arm64: defconfig: Enable CONFIG_PINCTRL_IMX8DXL by default
  arm64: configs: Enable sun50i cpufreq nvmem
  ARM: shmobile: defconfig: Refresh for v5.7-rc1
  ARM: defconfig: u8500: Enable new drivers for samsung-golden
  ARM: configs: sunxi: Add sun8i analog codec
  arm64: defconfig: Enable Qualcomm CAMCC, CAMSS and CCI drivers
  ARM: configs: at91: sama5: enable MCP16502 regulator
  ARM: configs: at91: sama5: enable SAMA5D2_PIOBU
  ARM: exynos_defconfig: Compile MAC80211/CFG80211 as modules
  ...

Merge tag 'arm-soc-5.8' of git://git./linux/kernel/git/soc/soc

Pull ARM SoC updates from Arnd Bergmann:
"One new platform gets added, the Realtek RTD1195, which is an older
  Cortex-a7 based relative of the RTD12xx chips that are already
  supported in arch/arm64. The platform may also be extended to support
  running 32-bit kernels on those 64-bit chips for memory-constrained
  machines.

  In the Renesas shmobile platform, we gain support for "RZ/G1H" or
  R8A7742, an eight-core chip based on Cortex-A15 and Cortex-A7 cores,
  originally released in 2016 as one of the last high-end 32-bit
  designs.

  There is ongoing cleanup for the integrator, tegra, imx, and omap2
  platforms, with integrator getting very close to the goal of having
  zero code in arch/arm/, and omap2 moving more of the chip specifics
  from old board code into device tree files.

  The Versatile Express platform is made more modular, with built-in
  drivers now becoming loadable modules. This is part of a greater
  effort for the Android OS to have a common kernel binary for all
  platforms and any platform specific code in loadable modules.

  The PXA platform drops support for Compulab's pxa2xx boards that had
  rather unusual flash and PCI drivers but no known users remaining. All
  device drivers specific to those boards can now get removed as well.

  Across platforms, there is ongoing cleanup, with Geert and Rob
  revisiting some a lot of Kconfig options"

* tag 'arm-soc-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (94 commits)
  ARM: omap2: fix omap5_realtime_timer_init definition
  ARM: zynq: Don't select CONFIG_ICST
  ARM: OMAP2+: Fix regression for using local timer on non-SMP SoCs
  clk: versatile: Fix kconfig dependency on COMMON_CLK_VERSATILE
  ARM: davinci: fix build failure without I2C
  power: reset: vexpress: fix build issue
  power: vexpress: cleanup: use builtin_platform_driver
  power: vexpress: add suppress_bind_attrs to true
  Revert "ARM: vexpress: Don't select VEXPRESS_CONFIG"
  MAINTAINERS: pxa: remove Compulab arm/pxa support
  ARM: pxa: remove Compulab pxa2xx boards
  bus: arm-integrator-lm: Fix return value check in integrator_ap_lm_probe()
  soc: imx: move cpu code to drivers/soc/imx
  ARM: imx: move cpu definitions into a header
  ARM: imx: use device_initcall for imx_soc_device_init
  ARM: imx: pcm037: make pcm970_sja1000_platform_data static
  bus: ti-sysc: Timers no longer need legacy quirk handling
  ARM: OMAP2+: Drop old timer code for dmtimer and 32k counter
  ARM: dts: Configure system timers for omap2
  ARM: dts: Configure system timers for ti81xx
  ...

Kconfig: add config option for asm goto w/ outputs

This allows C code to make use of compilers with support for output
variables along the fallthrough path via preprocessor define:

  CONFIG_CC_HAS_ASM_GOTO_OUTPUT

[ This is not used anywhere yet, and currently released compilers don't
  support this yet, but it's coming, and I have some local experimental
  patches to take advantage of it when it does   - Linus ]

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'akpm' (patches from Andrew)

Merge yet more updates from Andrew Morton:

- More MM work. 100ish more to go. Mike Rapoport's "mm: remove
   __ARCH_HAS_5LEVEL_HACK" series should fix the current ppc issue

- Various other little subsystems

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
  lib/ubsan.c: fix gcc-10 warnings
  tools/testing/selftests/vm: remove duplicate headers
  selftests: vm: pkeys: fix multilib builds for x86
  selftests: vm: pkeys: use the correct page size on powerpc
  selftests/vm/pkeys: override access right definitions on powerpc
  selftests/vm/pkeys: test correct behaviour of pkey-0
  selftests/vm/pkeys: introduce a sub-page allocator
  selftests/vm/pkeys: detect write violation on a mapped access-denied-key page
  selftests/vm/pkeys: associate key on a mapped page and detect write violation
  selftests/vm/pkeys: associate key on a mapped page and detect access violation
  selftests/vm/pkeys: improve checks to determine pkey support
  selftests/vm/pkeys: fix assertion in test_pkey_alloc_exhaust()
  selftests/vm/pkeys: fix number of reserved powerpc pkeys
  selftests/vm/pkeys: introduce powerpc support
  selftests/vm/pkeys: introduce generic pkey abstractions
  selftests: vm: pkeys: use the correct huge page size
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really random
  selftests/vm/pkeys: fix assertion in pkey_disable_set/clear()
  selftests/vm/pkeys: fix pkey_disable_clear()
  selftests: vm: pkeys: add helpers for pkey bits
  ...

lib/ubsan.c: fix gcc-10 warnings

The latest compiler expects slightly different function prototypes
for the ubsan helpers:

  lib/ubsan.c:192:6: error: conflicting types for built-in function '__ubsan_handle_add_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    192 | void __ubsan_handle_add_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:200:6: error: conflicting types for built-in function '__ubsan_handle_sub_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    200 | void __ubsan_handle_sub_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:207:6: error: conflicting types for built-in function '__ubsan_handle_mul_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    207 | void __ubsan_handle_mul_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:214:6: error: conflicting types for built-in function '__ubsan_handle_negate_overflow'; expected 'void(void *, void *)' [-Werror=builtin-declaration-mismatch]
    214 | void __ubsan_handle_negate_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:234:6: error: conflicting types for built-in function '__ubsan_handle_divrem_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    234 | void __ubsan_handle_divrem_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Change the Linux implementation to match these, using a local typed
pointer.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Julien Grall <julien.grall@arm.com>
Link: http://lkml.kernel.org/r/20200429185948.4189600-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/selftests/vm: remove duplicate headers

Code cleanup: Remove duplicate headers which are included twice.

Signed-off-by: Jagadeesh Pagadala <jagdsh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Link: http://lkml.kernel.org/r/1587278984-18847-1-git-send-email-jagdsh.linux@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: vm: pkeys: fix multilib builds for x86

This ensures that both 32-bit and 64-bit binaries are generated when this
is built on a x86_64 system. Most of the changes have been borrowed from
tools/testing/selftests/x86/Makefile.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/0326a442214d7a1b970d38296e63df3b217f5912.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: vm: pkeys: use the correct page size on powerpc

Both 4K and 64K pages are supported on powerpc.  Parts of the selftest
code perform alignment computations based on the PAGE_SIZE macro which is
currently hardcoded to 64K for powerpc.  This causes some test failures on
kernels configured with 4K page size.

In some cases, we need to enforce function alignment on page size.  Since
this can only be done at build time, 64K is used as the alignment factor
as that also ensures 4K alignment.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/5dcdfbf3353acdc90f315172e800b49f5ca21299.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: override access right definitions on powerpc

Some platforms hardcode the x86 values for PKEY_DISABLE_ACCESS
and PKEY_DISABLE_WRITE such as those in:
/usr/include/bits/mman-shared.h.

This overrides the definitions with correct values for powerpc.

[sandipan@linux.ibm.com: fix powerpc access right definitions]
Link: http://lkml.kernel.org/r/1ba86fd8a94f38131cfe2d9f277001dd1ad1d34e.1588959697.git.sandipan@linux.ibm.com
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/f6eb38cb3a1e12eb2cdc9da6300bc5a5dfba0db9.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: test correct behaviour of pkey-0

Ensure that pkey-0 is allocated on start and that it can be attached
dynamically in various modes, without failures.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/9b7c54a9b4261894fe0c7e884c70b87214ff8fbb.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: introduce a sub-page allocator

This introduces a new allocator that allocates 4K hardware pages to back
64K linux pages. This allocator is available only on powerpc.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/c4a82fa962ec71015b994fab1aaf83bdfd091553.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: detect write violation on a mapped access-denied-key page

Detect write-violation on a page to which access-disabled key is
associated much after the page is mapped.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/6a7dd4069ee18a2a51b207a55aa197f3f3c59753.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: associate key on a mapped page and detect write violation

Detect write-violation on a page to which write-disabled key is associated
much after the page is mapped.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/6bfe3b3832f8bcfb07d7f2cf116b45197f4587dd.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: associate key on a mapped page and detect access violation

Detect access-violation on a page to which access-disabled key is
associated much after the page is mapped.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/4a19cf9252c03dd883887e9002881599e6900d06.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: improve checks to determine pkey support

For the pkeys subsystem to work, both the CPU and the kernel need to have
support. So, additionally check if the kernel supports pkeys apart from
the CPU feature checks.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/8fb76c63ebdadcf068ecd2d23731032e195cd364.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: fix assertion in test_pkey_alloc_exhaust()

Some pkeys which are valid on the hardware are reserved and not available
for application use.  These keys cannot be allocated.

test_pkey_alloc_exhaust() tries to account for these and has an assertion
which validates if all available pkeys have been exahaustively allocated.
However, the expression that is currently used is only valid for x86.  On
powerpc, a pkey is additionally reserved as compared to x86.  Hence, the
assertion is made to use an arch-specific helper to get the correct count
of reserved pkeys.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/38b08d0318820ae46af3aa6048384fd8056c3df7.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: fix number of reserved powerpc pkeys

The number of reserved pkeys in a PowerNV environment is different from
that on PowerVM or KVM.

Tested on PowerVM and PowerNV environments.

Signed-off-by: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/0341a0ca961166814b44c9e724774672c18d54ca.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: introduce powerpc support

This makes use of the abstractions added earlier and introduces support
for powerpc.

For powerpc, after receiving the SIGSEGV, the signal handler must
explicitly restore access permissions for the faulting pkey to allow the
test to continue. As this makes use of pkey_access_allow(), all of its
dependencies and other similar functions have been moved ahead of the
signal handler.

[sandipan@linux.ibm.com: fix powerpc access right updates]
Link: http://lkml.kernel.org/r/5f65cf37be993760de8112a88da194e3ccbb2bf8.1588959697.git.sandipan@linux.ibm.com
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/b121e9fd33789ed9195276e32fe4e80bb6b88a31.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: introduce generic pkey abstractions

This introduces some generic abstractions and provides the corresponding
architecture-specfic implementations for these abstractions.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/1c977915e69fb7767fb0dbd55ac7656554b15b93.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: vm: pkeys: use the correct huge page size

The huge page size can vary across architectures. This will ensure that
the correct huge page size is used when accessing the hugetlb controls
under sysfs. Instead of using a hardcoded page size (i.e. 2MB), this now
uses the HPAGE_SIZE macro which is arch-specific.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/66882a5d6e45c73c3a52bc4aef9754e48afa4f88.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: fix alloc_random_pkey() to make it really random

alloc_random_pkey() was allocating the same pkey every time. Not all
pkeys were geting tested. This fixes it.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/0162f55816d4e783a0d6e49e554d0ab9a3c9a23b.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: fix assertion in pkey_disable_set/clear()

In some cases, a pkey's bits need not necessarily change in a way that the
value of the pkey register increases when performing a pkey_disable_set()
or decreases when performing a pkey_disable_clear().

For example, on powerpc, if a pkey's current state is PKEY_DISABLE_ACCESS
and we perform a pkey_write_disable() on it, the bits still remain the
same. We will observe something similar when the pkey's current state is
0 and a pkey_access_enable() is performed on it.

Either case would cause some assertions to fail. This fixes the problem.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/8240665131e43fc93eed4eea8194676c1ea39a7f.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: fix pkey_disable_clear()

Currently, pkey_disable_clear() sets the specified bits instead clearing
them. This has been dead code up to now because its only callers i.e.
pkey_access/write_allow() are also unused.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/1f70bca60330a85dca42c3cd98212bb1cdf5a076.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: vm: pkeys: add helpers for pkey bits

This introduces some functions that help with setting or clearing bits of
a particular pkey. This also adds an abstraction for getting a pkey's bit
position in the pkey register as this may vary across architectures.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/2ad9705f4f68ca7e72155cc583415e5a979546f1.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: vm: pkeys: Use sane types for pkey register

The size of the pkey register can vary across architectures. This
converts the data type of all its references to u64 in preparation for
multi-arch support.

To keep the definition of the u64 type consistent and remove format
specifier related warnings, __SANE_USERSPACE_TYPES__ is defined as
suggested by Michael Ellerman.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/d3e271798455d940e395e56e1ff1e82a31bcb7aa.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: make gcc check arguments of sigsafe_printf()

This will help us ensure we print pkey_reg_t values correctly in different
architectures.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/b40b7a95fdd4045d62530a2a34452934caf3b0bc.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: move some definitions to arch-specific header

In preparation for multi-arch support, move definitions which
have arch-specific values to x86-specific header.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/d58eba2930059c8b209eefd6d5b48fe922a5b010.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: move generic definitions to header file

Moved all the generic definition and helper functions to the
header file.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/57177f99e92a51295956715d5f2d5688a4d13927.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/vm/pkeys: rename all references to pkru to a generic name

This renames PKRU references to "pkey_reg" or "pkey" based on
the usage.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/2c6970bc6d2e99796cd5cc1101bd2ecf7eccb937.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests/x86/pkeys: move selftests to arch-neutral directory

Patch series "selftests, powerpc, x86: Memory Protection Keys", v19.

Memory protection keys enables an application to protect its address space
from inadvertent access by its own code.

This feature is now enabled on powerpc and has been available since
4.16-rc1. The patches move the selftests to arch neutral directory and
enhance their test coverage.

Tested on powerpc64 and x86_64 (Skylake-SP).

This patch (of 24):

Move selftest files from tools/testing/selftests/x86/ to
tools/testing/selftests/vm/.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/14d25194c3e2e652e0047feec4487e269e76e8c9.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/relay.c: fix read_pos error when multiple readers

When reading, read_pos should start with bytes_consumed, not file->f_pos.
Because when there is more than one reader, the read_pos corresponding to
file->f_pos may have been consumed, which will cause the data that has
been consumed to be read and the bytes_consumed update error.

Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>e
Link: http://lkml.kernel.org/r/1579691175-28949-1-git-send-email-yangpc@wangsu.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/relay.c: handle alloc_percpu returning NULL in relay_open

alloc_percpu() may return NULL, which means chan->buf may be set to NULL.
In that case, when we do *per_cpu_ptr(chan->buf, ...), we dereference an
invalid pointer:

  BUG: Unable to handle kernel data access at 0x7dae0000
  Faulting instruction address: 0xc0000000003f3fec
  ...
  NIP relay_open+0x29c/0x600
  LR relay_open+0x270/0x600
  Call Trace:
     relay_open+0x264/0x600 (unreliable)
     __blk_trace_setup+0x254/0x600
     blk_trace_setup+0x68/0xa0
     sg_ioctl+0x7bc/0x2e80
     do_vfs_ioctl+0x13c/0x1300
     ksys_ioctl+0x94/0x130
     sys_ioctl+0x48/0xb0
     system_call+0x5c/0x68

Check if alloc_percpu returns NULL.

This was found by syzkaller both on x86 and powerpc, and the reproducer
it found on powerpc is capable of hitting the issue as an unprivileged
user.

Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers")
Reported-by: syzbot+1e925b4b836afe85a1c6@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+587b2421926808309d21@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+58320b7171734bf79d26@syzkaller.appspotmail.com
Reported-by: syzbot+d6074fb08bdb2e010520@syzkaller.appspotmail.com
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Akash Goel <akash.goel@intel.com>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Salvatore Bonaccorso <carnil@debian.org>
Cc: <stable@vger.kernel.org> [4.10+]
Link: http://lkml.kernel.org/r/20191219121256.26480-1-dja@axtens.net
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rapidio: convert get_user_pages() --> pin_user_pages()

This code was using get_user_pages_fast(), in a "Case 2" scenario
(DMA/RDMA), using the categorization from [1]. That means that it's time
to convert the get_user_pages_fast() + put_page() calls to
pin_user_pages_fast() + unpin_user_pages() calls.

There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.

[1] Documentation/core-api/pin_user_pages.rst

[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/

Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Link: http://lkml.kernel.org/r/20200517235620.205225-3-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rapidio: avoid data race between file operation callbacks and mport_cdev_add().

Fields of md(mport_dev) are set after cdev_device_add(). However, the
file operation callbacks can be called after cdev_device_add() and
therefore accesses to fields of md in the callbacks can race with the rest
of the mport_cdev_add() function.

One such example is INIT_LIST_HEAD(&md->portwrites) in mport_cdev_add(),
the list is initialised after cdev_device_add(). This can race with
list_add_tail(&pw_filter->md_node,&md->portwrites) in
rio_mport_add_pw_filter() which is called by unlocked_ioctl.

To avoid such data races use cdev_device_add() after initializing md.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Pavel Andrianov <andrianov@ispras.ru>
Link: http://lkml.kernel.org/r/20200426112950.1803-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

exec: open code copy_string_kernel

Currently copy_string_kernel is just a wrapper around copy_strings that
simplifies the calling conventions and uses set_fs to allow passing a
kernel pointer. But due to the fact the we only need to handle a single
kernel argument pointer, the logic can be sigificantly simplified while
getting rid of the set_fs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200501104105.2621149-3-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

exec: simplify the copy_strings_kernel calling convention

copy_strings_kernel is always used with a single argument,
adjust the calling convention to that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200501104105.2621149-2-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/kprobes.c: convert to use DEFINE_SEQ_ATTRIBUTE macro

Use DEFINE_SEQ_ATTRIBUTE macro to simplify the code.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200509064031.181091-4-wangkefeng.wang@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmstat.c: convert to use DEFINE_SEQ_ATTRIBUTE macro

Use DEFINE_SEQ_ATTRIBUTE macro to simplify the code.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200509064031.181091-3-wangkefeng.wang@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/seq_file.h: introduce DEFINE_SEQ_ATTRIBUTE() helper macro

Patch series "seq_file: Introduce DEFINE_SEQ_ATTRIBUTE() helper macro".

As discussed in
https://lore.kernel.org/lkml/20191129222310.GA3712618@kroah.com/, we could
introduce a new helper macro to reduce losts of boilerplate code, vmstat
and kprobes is the example which covert to use it, if this is accepted, I
will send out more cleanups.

This patch (of 3):

Introduce DEFINE_SEQ_ATTRIBUTE() helper macro to decrease code duplication.

[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200509064031.181091-1-wangkefeng.wang@huawei.com
Link: http://lkml.kernel.org/r/20200509064031.181091-2-wangkefeng.wang@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/seq_file.c: seq_read: Update pr_info_ratelimited

Use a more common logging style.

Add and use pr_fmt, coalesce the format string, align arguments,
use better grammar.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vasily Averin <vvs@virtuozzo.com>
Link: http://lkml.kernel.org/r/96ff603230ca1bd60034c36519be3930c3a3a226.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fat: improve the readahead for FAT entries

Current readahead for FAT entries is very simple but is having some flaws,
so it is not working well for some environments.  This patch improves the
readahead more or less.

The key points of modification are,

  - make the readahead size tunable by using bdi->ra_pages
  - care the bdi->io_pages to avoid the small size I/O request
  - update readahead window before fully exhausting

With this patch, on slow USB connected 2TB hdd:

[before]
383.18sec

[after]
51.03sec

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: hyeongseok.kim <hyeongseok.kim@lge.com>
Reviewed-by: hyeongseok.kim <hyeongseok.kim@lge.com>
Link: http://lkml.kernel.org/r/87d08e1dlh.fsf@mail.parknet.co.jp
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fat: don't allow to mount if the FAT length == 0

If FAT length == 0, the image doesn't have any data. And it can be the
cause of overlapping the root dir and FAT entries.

Also Windows treats it as invalid format.

Reported-by: syzbot+6f1624f937d9d6911e2d@syzkaller.appspotmail.com
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/87r1wz8mrd.fsf@mail.parknet.co.jp
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init: allow distribution configuration of default init

Some init systems (eg.  systemd) have init at their own paths, for
example, /usr/lib/systemd/systemd.  A compatibility symlink to one of the
hardcoded init paths is provided by another package, usually named
something like systemd-sysvcompat or similar.

Currently distro maintainers who are hands-off on the bootloader are more
or less required to include those compatibility links as part of their
base distribution, because it's hard to migrate away from them since
there's a risk some users will not get the message to set init= on the
kernel command line appropriately.

Moreover, for distributions where the init system is something the
distribution itself is opinionated about (eg.  Arch, which has systemd in
the required `base` package), we could usually reasonably configure this
ahead of time when building the distribution kernel.  However, we
currently simply don't have any way to configure the kernel to do this.
Here's an example discussion where removing sysvcompat was discussed by
distro maintainers[0].

This patch adds a new Kconfig tunable, CONFIG_DEFAULT_INIT, which if set
is tried before the hardcoded fallback list.  So the order of precedence
is now thus:

1. init= on command line (on failure: panic)
2. CONFIG_DEFAULT_INIT (on failure: try #3)
3. Hardcoded fallback list (on failure: panic)

This new config parameter will allow distribution maintainers to move away
from these compatibility links safely, without having to worry that their
users might not have the right init=.

There are also two other benefits of this over having the distribution
maintain a symlink:

1. One of the value propositions over simply having distributions
   maintain a /sbin/init symlink via a package is that it also frees
   distributions which have a preferred default, but not mandatory, init
   system from having their package manager fight with their users for
   control of /{s,}bin/init.  Instead, the distribution simply makes
   their preference known in CONFIG_DEFAULT_INIT, and if the user
   installs another init system and uninstalls the default one they can
   still make use of /{s,}bin/init and friends for their own uses. This
   makes more cases Just Work(tm) without the user having to perform
   extra configuration via init=.

2. Since before this we don't know which path the distribution actually
   _intends_ to serve init from, we don't pr_err if it is simply
   missing, and usually will just silently put the user in a /bin/sh
   shell. Now that the distribution can make a declaration of intent, we
   can be more vocal when this init system fails to launch for any
   reason, even if it's simply because no file exists at that location,
   speeding up the palaver of init/mount dependency/etc debugging a bit.

[0]: https://lists.archlinux.org/pipermail/arch-dev-public/2019-January/029435.html

Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: http://lkml.kernel.org/r/20200522160234.GA1487022@chrisdown.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

elfnote: mark all .note sections SHF_ALLOC

ELFNOTE_START allows callers to specify flags for .pushsection assembler
directives.  All callsites but ELF_NOTE use "a" for SHF_ALLOC.  For vdso's
that explicitly use ELF_NOTE_START and BUILD_SALT, the same section is
specified twice after preprocessing, once with "a" flag, once without.
Example:

.pushsection .note.Linux, "a", @note ;
.pushsection .note.Linux, "", @note ;

While GNU as allows this ordering, it warns for the opposite ordering,
making these directives position dependent.  We'd prefer not to precisely
match this behavior in Clang's integrated assembler.  Instead, the non
__ASSEMBLY__ definition of ELF_NOTE uses
__attribute__((section(".note.Linux"))) which is created with SHF_ALLOC,
so let's make the __ASSEMBLY__ definition of ELF_NOTE consistent with C
and just always use "a" flag.

This allows Clang to assemble a working mainline (5.6) kernel via:
$ make CC=clang AS=clang

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/913
Link: http://lkml.kernel.org/r/20200325231250.99205-1-ndesaulniers@google.com
Debugged-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_elf: remove redundant elf_map ifndef

The ifndef was added a long time ago to support archs that would define
their own mapping function. The last user was the metag arch which was
removed from the tree, and as such there are no users left. Let's kill
it.

Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200402161543.4119-1-ailiop@suse.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: use patch subject when reading from stdin

While "git am" can apply an mbox file containing multiple patches (e.g.
as created by b4[1], or a patch bundle downloaded from patchwork),
checkpatch does not have proper support for that.  When operating on an
mbox, checkpatch will merge all detected tags, and complain falsely about
duplicates:

    WARNING: Duplicate signature

As modifying checkpatch to reset state in between each patch is a lot of
work, a simple solution is splitting the mbox into individual patches, and
invoking checkpatch for each of them.  Fortunately checkpatch can read a
patch from stdin, so the classic "formail" tool can be used to split the
mbox, and pipe all individual patches to checkpatch:

    formail -s scripts/checkpatch.pl < my-mbox

However, when reading a patch file from standard input, checkpatch calls
it "Your patch", and reports its state as:

    Your patch has style problems, please review.

or:

    Your patch has no obvious style problems and is ready for submission.

Hence it can be difficult to identify which patches need to be reviewed
and improved.

Fix this by replacing "Your patch" by (the first line of) the email
subject, if present.

Note that "git mailsplit" can also be used to split an mbox, but it will
create individual files for each patch, thus requiring cleanup afterwards.
Formail does not have this disadvantage.

[1] https://git.kernel.org/pub/scm/utils/b4/b4.git

[joe@perches.com: reduce cpu usage]
Link: http://lkml.kernel.org/r/c9d89bb24c7414142414c60371e210fdcf4617d2.camel@perches.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200505132613.17452-1-geert+renesas@glider.be
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: disallow --git and --file/--fix

Don't allow these options to be combined.

Miscellanea:

o Add missing $P: to some die("reason message") output

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/3dc7bdaa58490f5906efc11a4d6113e42a087723.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: look for c99 comments in ctx_locate_comment

Some checks look for comments around a specific function like
read_barrier_depends.

Extend the check to support both c89 and c90 comment styles.

c89 /* comment */
or
c99 // comment

For c99 comments, only look a 3 single lines, the line being scanned,
the line above and the line below the line being scanned rather than
the patch diff context.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/65cb075435d2f385a53c77571b491b2b09faaf8e.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: additional MAINTAINER section entry ordering checks

There is a preferred order for the entries in MAINTAINERS sections.

See commits 3b50142d8528 ("MAINTAINERS: sort field names for all
entries") and 6680125ea5a2 ("MAINTAINERS: list the section entries in
the preferred order")

Add checkpatch tests to try to keep that ordering.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: http://lkml.kernel.org/r/17677130b3ca62d79817e6a22546bad39d7e81b4.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/bitops.h: avoid clang shift-count-overflow warnings

Clang normally does not warn about certain issues in inline functions when
it only happens in an eliminated code path. However if something else
goes wrong, it does tend to complain about the definition of hweight_long()
on 32-bit targets:

  include/linux/bitops.h:75:41: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
          return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
                                                 ^~~~~~~~~~~~
  include/asm-generic/bitops/const_hweight.h:29:49: note: expanded from macro 'hweight64'
   define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))
                                                  ^~~~~~~~~~~~~~~~~~~~
  include/asm-generic/bitops/const_hweight.h:21:76: note: expanded from macro '__const_hweight64'
   define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
                                                                             ^  ~~
  include/asm-generic/bitops/const_hweight.h:20:49: note: expanded from macro '__const_hweight32'
   define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
                                                  ^
  include/asm-generic/bitops/const_hweight.h:19:72: note: expanded from macro '__const_hweight16'
   define __const_hweight16(w) (__const_hweight8(w)  + __const_hweight8((w)  >> 8 ))
                                                                         ^
  include/asm-generic/bitops/const_hweight.h:12:9: note: expanded from macro '__const_hweight8'
            (!!((w) & (1ULL << 2))) +     \

Adding an explicit cast to __u64 avoids that warning and makes it easier
to read other output.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: http://lkml.kernel.org/r/20200505135513.65265-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib: make a test module with set/clear bit

Test some bit clears/sets to make sure assembly doesn't change, and that
the set_bit and clear_bit functions work and don't cause sparse warnings.

Instruct Kbuild to build this file with extra warning level -Wextra, to
catch new issues, and also doesn't hurt to build with C=1.

This was used to test changes to arch/x86/include/asm/bitops.h.

In particular, sparse (C=1) was very concerned when the last bit before a
natural boundary, like 7, or 31, was being tested, as this causes sign
extension (0xffffff7f) for instance when clearing bit 7.

Recommended usage:

  make defconfig
  scripts/config -m CONFIG_TEST_BITOPS
  make modules_prepare
  make C=1 W=1 lib/test_bitops.ko
  objdump -S -d lib/test_bitops.ko
  insmod lib/test_bitops.ko
  rmmod lib/test_bitops.ko

<check dmesg>, there should be no compiler/sparse warnings and no
error messages in log.

Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
CcL Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/flex_proportions.c: cleanup __fprop_inc_percpu_max

If the given type has fraction smaller than max_frac/FPROP_FRAC_BASE, the
code could be modified to call __fprop_inc_percpu() directly and easier to
understand. After this patch, fprop_reflect_period_percpu() will be
called twice, and quicky return on pl->period == p->period test, so it
would not result to significant downside of performance.

Thanks for Jan's guidance.

Signed-off-by: Tan Hu <tan.hu@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: <xue.zhihong@zte.com.cn>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Cc: <wang.liang82@zte.com.cn>
Link: http://lkml.kernel.org/r/1589004753-27554-1-git-send-email-tan.hu@zte.com.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/percpu-refcount.c: use a more common logging style

Remove the trailing newline from the used-once pr_fmt and add it to the
single use of pr_<level> in this code to use a more common logging style.

Miscellanea:

o Use %lu in the pr_debug format and remove the unnecessary cast

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: http://lkml.kernel.org/r/47372467902a047c03b0fd29aab56e0c38d3f848.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/zlib: remove outdated and incorrect pre-increment optimization

The zlib inflate code has an old micro-optimization based on the
assumption that for pre-increment memory accesses, the compiler will
generate code that fits better into the processor's pipeline than what
would be generated for post-increment memory accesses.

This optimization was already removed in upstream zlib in 2016:
https://github.com/madler/zlib/commit/9aaec95e8211

This optimization causes UB according to C99, which says in section 6.5.6
"Additive operators": "If both the pointer operand and the result point to
elements of the same array object, or one past the last element of the
array object, the evaluation shall not produce an overflow; otherwise, the
behavior is undefined".

This UB is not only a theoretical concern, but can also cause trouble for
future work on compiler-based sanitizers.

According to the zlib commit, this optimization also is not optimal
anymore with modern compilers.

Replace uses of OFF, PUP and UP_UNALIGNED with their definitions in the
POSTINC case, and remove the macro definitions, just like in the upstream
patch.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200507123112.252723-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/test_lockup.c: make test_inode static

Fix the following sparse warning:

lib/test_lockup.c:145:14: warning: symbol 'test_inode' was not declared.
Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200417074021.46411-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib: Add might_fault() to strncpy_from_user.

When updating a piece of broken logic from using get_user to
strncpy_from_user, we noticed that a warning which is expected when
calling a function that might fault from an atomic context with
pagefaults enabled disappeared.

Not having this warning in place can lead to calling strncpy_from_user
from an atomic context and eventually kernel crashes/stack corruption.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20200414225705.255711-1-kpsingh@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/math: avoid trailing newline hidden in pr_fmt()

pr_xxx() functions usually have a newline at the end of the logging
message.

Here, this newline is added via the 'pr_fmt' macro.

In order to be more consistent with other files, use a more standard
convention and put these newlines back in the messages themselves and
remove it from the pr_fmt macro.

While at it, use __func__ instead of hardcoding a function name in the
last message.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200409163234.22830-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

get_maintainer: fix unexpected behavior for path/to//file (double slashes)

get_maintainer behaves differently if there is a double sequential forward
slash in a filename because the total number of slashes in a filename is
used to match MAINTAINERS file patterns.

For example:

(with double slash)
  $ ./scripts/get_maintainer.pl -f drivers/gpu/drm//lima
  David Airlie <airlied@linux.ie> (maintainer:DRM DRIVERS)
  Daniel Vetter <daniel@ffwll.ch> (maintainer:DRM DRIVERS,commit_signer:3/42=7%)
  Qiang Yu <yuq825@gmail.com> (commit_signer:36/42=86%,authored:24/42=57%)
  Vasily Khoruzhick <anarsoul@gmail.com> (commit_signer:26/42=62%)
  Krzysztof Kozlowski <krzk@kernel.org> (commit_signer:5/42=12%,authored:5/42=12%)
  Emil Velikov <emil.velikov@collabora.com> (commit_signer:4/42=10%)
  dri-devel@lists.freedesktop.org (open list:DRM DRIVERS)
  linux-kernel@vger.kernel.org (open list)

(without double slash)
  $ ./scripts/get_maintainer.pl -f drivers/gpu/drm/lima
  Qiang Yu <yuq825@gmail.com> (maintainer:DRM DRIVERS FOR LIMA)
  David Airlie <airlied@linux.ie> (maintainer:DRM DRIVERS)
  Daniel Vetter <daniel@ffwll.ch> (maintainer:DRM DRIVERS)
  dri-devel@lists.freedesktop.org (open list:DRM DRIVERS FOR LIMA)
  lima@lists.freedesktop.org (moderated list:DRM DRIVERS FOR LIMA)
  linux-kernel@vger.kernel.org (open list)

So reduce consecutive double slashes to a single slash
by using File::Spec->canonpath().

from: https://perldoc.perl.org/File/Spec/Unix.html

canonpath()

No physical check on the filesystem, but a logical cleanup of a path.  On
UNIX eliminates successive slashes and successive "/.".

Reported-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/9a18b611813bb409fef15bc8927adab79eb9be43.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

get_maintainer: add email addresses from .yaml files

.yaml files can contain maintainer/author addresses and it seems unlikely
or unnecessary that individual MAINTAINER file section entries for each
.yaml file will be created.

So add the email addresses found in .yaml files to the default
get_maintainer output.

The email addresses are marked with "(in file)" when using the "--roles"
or "--rolestats" options.

Miscellanea:

o Change $file_emails to $email_file_emails to avoid visual
naming conflicts with @file_emails

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: http://lkml.kernel.org/r/e85006456d9dbae55286c67ac5263668a72f5b58.1588022228.git.joe@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

user.c: make uidhash_table static

Fix the following sparse warning:

kernel/user.c:85:19: warning: symbol 'uidhash_table' was not declared.
Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200413082146.22737-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

proc: rename "catch" function argument

"catch" is reserved keyword in C++, rename it to something both gcc and
g++ accept.

Rename "ign" for symmetry.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200331210905.GA31680@avx2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

zcomp: Use ARRAY_SIZE() for backends list

Instead of keeping NULL terminated array switch to use ARRAY_SIZE()
which helps to further clean up.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: http://lkml.kernel.org/r/20200508100758.51644-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/mm.h: return true in cpupid_pid_unset()

Fix the following coccicheck warning:

include/linux/mm.h:1371:8-9: WARNING: return of 0/1 in function 'cpupid_pid_unset' with return type bool

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200422071816.48879-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: use false for bool variable

Fixes coccicheck warnings:

  mm/zbud.c:246:1-20: WARNING: Assignment of 0/1 to bool variable
  mm/mremap.c:777:2-8: WARNING: Assignment of 0/1 to bool variable
  mm/huge_memory.c:525:9-10: WARNING: return of 0/1 in function 'is_transparent_hugepage' with return type bool

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1586835930-47076-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory: fix a typo in comment "attampt"->"attempt"

There is a comment in typo, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200411004043.14686-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page-writeback: fix a typo in comment "effictive"->"effective"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200411003513.14613-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/sparse: fix a typo in comment "convienence"->"convenience"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200411002955.14545-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/slub: fix a typo in comment "disambiguiation"->"disambiguation"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/20200411002247.14468-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: fix a typo in comment "strucure"->"structure"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411064723.15855-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, memcg: fix some typos in memcontrol.c

There are some typos in comment, fix them.

s/responsiblity/responsibility
s/oflline/offline

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200411064246.15781-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/frontswap: fix some typos in frontswap.c

There are some typos in comment, fix them.

s/Fortunatly/Fortunately
s/taked/taken
s/necessory/necessary
s/shink/shrink

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200411064009.15727-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/filemap: fix a typo in comment "unneccssary"->"unnecessary"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411065141.15936-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/list_lru: fix a typo in comment "numbesr"->"numbers"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411071041.16161-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memblock: fix a typo in comment "implict"->"implicit"

There is a typo in commet, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411070701.16097-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/compaction: fix a typo in comment "pessemistic"->"pessimistic"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411070307.16021-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmsan: fix some typos in comment

There are some typos, fix them.

s/regsitration/registration
s/santity/sanity
s/decremeting/decrementing

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200411071544.16222-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb: fix a typos in comments

[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200410163714.14085-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: mmap: fix a typo in comment "compatbility"->"compatibility"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200410163206.14016-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: ksm: fix a typo in comment "alreaady"->"already"

There is a typo in comment, fix it.

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200410162427.13927-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: fix a typo in comment "recoreded"->"recorded"

There is a typo in comment, fix it.
s/recoreded/recorded

Signed-off-by: Ethon Paul <ethp@qq.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200410160328.13843-1-ethp@qq.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

    struct foo {
        int stuff;
        struct boo array[];
    };

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by this
change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied.  As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

[akpm@linux-foundation.org: fix build]
Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Baoquan He <bhe@redhat.com>
Link: http://lkml.kernel.org/r/1586599916-15456-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: disable the functionality for 32b

Memory hotlug is broken for 32b systems at least since c6f03e2903c9 ("mm,
memory_hotplug: remove zone restrictions") which has considerably reworked
how can be memory associated with movable/kernel zones.  The same is not
really trivial to achieve in 32b where only lowmem is the kernel zone.
While we can tweak this immediate problem around there are likely other
land mines hidden at other places.

It is also quite dubious that there is a real usecase for the memory
hotplug on 32b in the first place.  Low memory is just too small to be
hotplugable (for hot add) and generally unusable for hotremove.  Adding
more memory to highmem is also dubious because it would increase the low
mem or vmalloc space pressure for memmaps.

Restrict the functionality to 64b systems.  This will help future
development to focus on usecases that have real life application.  We can
remove this restriction in future in presence of a real life usecase of
course but until then make it explicit that hotplug on 32b is broken and
requires a non trivial amount of work to fix.

Robin said:
"32-bit Arm doesn't support memory hotplug, and as far as I'm aware
  there's little likelihood of it ever wanting to. FWIW it looks like
  SuperH is the only pure-32-bit architecture to have hotplug support at
  all"

Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Link: http://lkml.kernel.org/r/20200218100532.GA4151@dhcp22.suse.cz
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206401
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

device-dax: add memory via add_memory_driver_managed()

Currently, when adding memory, we create entries in /sys/firmware/memmap/
as "System RAM".  This will lead to kexec-tools to add that memory to the
fixed-up initial memmap for a kexec kernel (loaded via kexec_load()).  The
memory will be considered initial System RAM by the kexec'd kernel and can
no longer be reconfigured.  This is not what happens during a real reboot.

Let's add our memory via add_memory_driver_managed() now, so we won't
create entries in /sys/firmware/memmap/ and indicate the memory as "System
RAM (kmem)" in /proc/iomem.  This allows everybody (especially
kexec-tools) to identify that this memory is special and has to be treated
differently than ordinary (hotplugged) System RAM.

Before configuring the namespace:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-33fffffff : namespace0.0
3280000000-32ffffffff : PCI Bus 0000:00

After configuring the namespace:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00

After loading kmem before this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  150000000-33fffffff : dax0.0
    150000000-33fffffff : System RAM
3280000000-32ffffffff : PCI Bus 0000:00

After loading kmem after this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  150000000-33fffffff : dax0.0
    150000000-33fffffff : System RAM (kmem)
3280000000-32ffffffff : PCI Bus 0000:00

After a proper reboot:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00

Within the kexec kernel before this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  150000000-33fffffff : System RAM
3280000000-32ffffffff : PCI Bus 0000:00

Within the kexec kernel after this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
  140000000-1481fffff : namespace0.0
  148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00

/sys/firmware/memmap/ before this change:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)
0000000150000000-0000000340000000 (System RAM)

/sys/firmware/memmap/ after a proper reboot:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)

/sys/firmware/memmap/ after this change:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)

kexec-tools already seem to basically ignore any System RAM that's not on
top level when searching for areas to place kexec images - but also for
determining crash areas to dump via kdump.  Changing the resource name
won't have an impact.

Handle unloading of the driver after memory hotremove failed properly, by
duplicating the string if necessary.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-5-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec_file: don't place kexec images on IORESOURCE_MEM_DRIVER_MANAGED

Memory flagged with IORESOURCE_MEM_DRIVER_MANAGED is special - it won't be
part of the initial memmap of the kexec kernel and not all memory might be
accessible. Don't place any kexec images onto it.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-4-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: introduce add_memory_driver_managed()

Patch series "mm/memory_hotplug: Interface to add driver-managed system
ram", v4.

kexec (via kexec_load()) can currently not properly handle memory added
via dax/kmem, and will have similar issues with virtio-mem.  kexec-tools
will currently add all memory to the fixed-up initial firmware memmap.  In
case of dax/kmem, this means that - in contrast to a proper reboot - how
that persistent memory will be used can no longer be configured by the
kexec'd kernel.  In case of virtio-mem it will be harmful, because that
memory might contain inaccessible pieces that require coordination with
hypervisor first.

In both cases, we want to let the driver in the kexec'd kernel handle
detecting and adding the memory, like during an ordinary reboot.
Introduce add_memory_driver_managed().  More on the samentics are in patch
#1.

In the future, we might want to make this behavior configurable for
dax/kmem- either by configuring it in the kernel (which would then also
allow to configure kexec_file_load()) or in kexec-tools by also adding
"System RAM (kmem)" memory from /proc/iomem to the fixed-up initial
firmware memmap.

More on the motivation can be found in [1] and [2].

[1] https://lkml.kernel.org/r/20200429160803.109056-1-david@redhat.com
[2] https://lkml.kernel.org/r/20200430102908.10107-1-david@redhat.com

This patch (of 3):

Some device drivers rely on memory they managed to not get added to the
initial (firmware) memmap as system RAM - so it's not used as initial
system RAM by the kernel and the driver is under control.  While this is
the case during cold boot and after a reboot, kexec is not aware of that
and might add such memory to the initial (firmware) memmap of the kexec
kernel.  We need ways to teach kernel and userspace that this system ram
is different.

For example, dax/kmem allows to decide at runtime if persistent memory is
to be used as system ram.  Another future user is virtio-mem, which has to
coordinate with its hypervisor to deal with inaccessible parts within
memory resources.

We want to let users in the kernel (esp. kexec) but also user space
(esp. kexec-tools) know that this memory has different semantics and
needs to be handled differently:
1. Don't create entries in /sys/firmware/memmap/
2. Name the memory resource "System RAM ($DRIVER)" (exposed via
   /proc/iomem) ($DRIVER might be "kmem", "virtio_mem").
3. Flag the memory resource IORESOURCE_MEM_DRIVER_MANAGED

/sys/firmware/memmap/ [1] represents the "raw firmware-provided memory
map" because "on most architectures that firmware-provided memory map is
modified afterwards by the kernel itself".  The primary user is kexec on
x86-64.  Since commit d96ae5309165 ("memory-hotplug: create
/sys/firmware/memmap entry for new memory"), we add all hotplugged memory
to that firmware memmap - which makes perfect sense for traditional memory
hotplug on x86-64, where real HW will also add hotplugged DIMMs to the
firmware memmap.  We replicate what the "raw firmware-provided memory map"
looks like after hot(un)plug.

To keep things simple, let the user provide the full resource name instead
of only the driver name - this way, we don't have to manually
allocate/craft strings for memory resources.  Also use the resource name
to make decisions, to avoid passing additional flags.  In case the name
isn't "System RAM", it's special.

We don't have to worry about firmware_map_remove() on the removal path.
If there is no entry, it will simply return with -EINVAL.

We'll adapt dax/kmem in a follow-up patch.

[1] https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-firmware-memmap

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-1-david@redhat.com
Link: http://lkml.kernel.org/r/20200508084217.9160-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: handle memblocks only with CONFIG_ARCH_KEEP_MEMBLOCK

The comment in add_memory_resource() is stale: hotadd_new_pgdat() will no
longer call get_pfn_range_for_nid(), as a hotadded pgdat will simply span
no pages at all, until memory is moved to the zone/node via
move_pfn_range_to_zone() - e.g., when onlining memory blocks.

The only archs that care about memblocks for hotplugged memory (either for
iterating over all system RAM or testing for memory validity) are arm64,
s390x, and powerpc - due to CONFIG_ARCH_KEEP_MEMBLOCK. Without
CONFIG_ARCH_KEEP_MEMBLOCK, we can simply stop messing with memblocks.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Link: http://lkml.kernel.org/r/20200422155353.25381-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: set node_start_pfn of hotadded pgdat to 0

Patch series "mm/memory_hotplug: handle memblocks only with
CONFIG_ARCH_KEEP_MEMBLOCK", v1.

A hotadded node/pgdat will span no pages at all, until memory is moved to
the zone/node via move_pfn_range_to_zone() -> resize_pgdat_range - e.g.,
when onlining memory blocks.  We don't have to initialize the
node_start_pfn to the memory we are adding.

This patch (of 2):

Especially, there is an inconsistency:
- Hotplugging memory to a memory-less node with cpus: node_start_pf ==  0
- Offlining and removing last memory from a node: node_start_pfn == 0
- Hotplugging memory to a memory-less node without cpus: node_start_pfn != 0

As soon as memory is onlined, node_start_pfn is overwritten with the
actual start.  E.g., when adding two DIMMs but only onlining one of both,
only that DIMM (with online memory blocks) is spanned by the node.

Currently, the validity of node_start_pfn really is linked to
node_spanned_pages != 0.  With node_spanned_pages == 0 (e.g., before
onlining memory), it has no meaning.

So let's stop setting node_start_pfn, just to be overwritten via
move_pfn_range_to_zone().  This avoids confusion when looking at the code,
wondering which magic will be performed with the node_start_pfn in this
function, when hotadding a pgdat.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Link: http://lkml.kernel.org/r/20200422155353.25381-1-david@redhat.com
Link: http://lkml.kernel.org/r/20200422155353.25381-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: remove is_mem_section_removable()

Fortunately, all users of is_mem_section_removable() are gone. Get rid of
it, including some now unnecessary functions.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Oscar Salvador <osalvador@suse.de>
Link: http://lkml.kernel.org/r/20200407135416.24093-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc/pseries/hotplug-memory: stop checking is_mem_section_removable()

In commit 53cdc1cb29e8 ("drivers/base/memory.c: indicate all memory blocks
as removable"), the user space interface to compute whether a memory block
can be offlined (exposed via /sys/devices/system/memory/memoryX/removable)
has effectively been deprecated.  We want to remove the leftovers of the
kernel implementation.

When offlining a memory block (mm/memory_hotplug.c:__offline_pages()),
we'll start by:
1. Testing if it contains any holes, and reject if so
2. Testing if pages belong to different zones, and reject if so
3. Isolating the page range, checking if it contains any unmovable pages

Using is_mem_section_removable() before trying to offline is not only
racy, it can easily result in false positives/negatives.  Let's stop
manually checking is_mem_section_removable(), and let device_offline()
handle it completely instead.  We can remove the racy
is_mem_section_removable() implementation next.

We now take more locks (e.g., memory hotplug lock when offlining and the
zone lock when isolating), but maybe we should optimize that
implementation instead if this ever becomes a real problem (after all,
memory unplug is already an expensive operation).  We started using
is_mem_section_removable() in commit 51925fb3c5c9 ("powerpc/pseries:
Implement memory hotplug remove in the kernel"), with the initial
hotremove support of lmbs.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Link: http://lkml.kernel.org/r/20200407135416.24093-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug: refrain from adding memory into an impossible node

A misbehaving qemu created a situation where the ACPI SRAT table
advertised one fewer proximity domains than intended.  The NFIT table did
describe all the expected proximity domains.  This caused the device dax
driver to assign an impossible target_node to the device, and when
hotplugged as system memory, this would fail with the following signature:

   BUG: kernel NULL pointer dereference, address: 0000000000000088
   #PF: supervisor read access in kernel mode
   #PF: error_code(0x0000) - not-present page
   PGD 80000001767d4067 P4D 80000001767d4067 PUD 10e0c4067 PMD 0
   Oops: 0000 [#1] SMP PTI
   CPU: 4 PID: 22737 Comm: kswapd3 Tainted: G           O      5.6.0-rc5 #9
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
   RIP: 0010:prepare_kswapd_sleep+0x7c/0xc0
   Code: 89 df e8 87 fd ff ff 89 c2 31 c0 84 d2 74 e6 0f 1f 44 00 00 48 8b 05 fb af 7a 01 48 63 93 88 1d 01 00 48 8b 84 d0 20 0f 00 00 <48> 3b 98 88 00 00 00 75 28 f0 80 a0 80 00 00 00 fe f0 80 a3 38 20
   RSP: 0018:ffffc900017a3e78 EFLAGS: 00010202
   RAX: 0000000000000000 RBX: ffff8881209e0000 RCX: 0000000000000000
   RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8881209e0e80
   RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000008000
   R10: 0000000000000000 R11: 0000000000000003 R12: 0000000000000003
   R13: 0000000000000003 R14: 0000000000000000 R15: ffffc900017a3ec8
   FS:  0000000000000000(0000) GS:ffff888318c00000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 0000000000000088 CR3: 0000000120b50002 CR4: 00000000001606e0
   Call Trace:
    kswapd+0x103/0x520
    kthread+0x120/0x140
    ret_from_fork+0x3a/0x50

Add a check in the add_memory path to fail if the node to which we are
adding memory is in the node_possible_map

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20200416225438.15208-1-vishal.l.verma@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: add kvfree_sensitive() for freeing sensitive data objects

For kvmalloc'ed data object that contains sensitive information like
cryptographic keys, we need to make sure that the buffer is always cleared
before freeing it.  Using memset() alone for buffer clearing may not
provide certainty as the compiler may compile it away.  To be sure, the
special memzero_explicit() has to be used.

This patch introduces a new kvfree_sensitive() for freeing those sensitive
data objects allocated by kvmalloc().  The relevant places where
kvfree_sensitive() can be used are modified to use it.

Fixes: 4f0882491a14 ("KEYS: Avoid false positive ENOMEM error on key read")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Link: http://lkml.kernel.org/r/20200407200318.11711-1-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kmap: consolidate kmap_prot definitions

Most architectures define kmap_prot to be PAGE_KERNEL.

Let sparc and xtensa define there own and define PAGE_KERNEL as the
default if not overridden.

[akpm@linux-foundation.org: coding style fixes]
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-16-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>