Even if RISC-V has supported the vDSO feature, the latency of the functions
for obtaining the system time is still expensive. It is because these
functions still trigger a corresponding system call in the process, which
slows down the response time. If we want to remove the system call to
reduce the latency, the kernel should have the ability to output the system
clock information to userspace. This patch introduces the vDSO common flow
to enable the kernel to achieve the above feature and uses "rdtime"
instruction to obtain the current time in the user space. Under this
condition, the latency cost by the ecall from U-mode to S-mode can be
eliminated. After applying this patch, the latency of gettimeofday()
measured on the HiFive unleashed board can be reduced by %61.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Add the missing header in file, it was lost in original implementation.

The warning message as follows:
 - no previous prototype for 'patch_text_nosync' [-Wmissing-prototypes]
 - no previous prototype for 'patch_text' [-Wmissing-prototypes]

Changed in v2:
 - Correct the typo of commit message.

Signed-off-by: Zong Li <zong.li@sifive.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

The head text section (i.e. _start, secondary_start_sbi, etc) and the
init section fall under same page table level-1 mapping.

Currently, the runtime CPU hotplug is broken because we are marking
init section as non-executable which in-turn marks head text section
as non-executable.

Further investigating other architectures, it seems marking the init
section as non-executable is redundant because the init section pages
are anyway poisoned and freed.

To fix broken runtime CPU hotplug, we simply remove the code marking
the init section as non-executable.

Fixes: d27c3c90

 ("riscv: add STRICT_KERNEL_RWX support")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

The RISC-V per-HART local interrupt controller driver is mandatory
for all RISC-V system (with/without MMU) hence we force select it
for CONFIG_RISCV (just like RISCV_TIMER).

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

The only thing do_IRQ() does is call handle_arch_irq function
pointer. We can very well call handle_arch_irq function pointer
directly from assembly and remove do_IRQ() function hence this
patch.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Instead of directly calling RISC-V timer interrupt handler from
RISC-V local interrupt conntroller driver, this patch implements
RISC-V timer interrupt as a per-CPU interrupt using per-CPU APIs
of Linux IRQ subsystem.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

The RISC-V per-HART local interrupt controller manages software
interrupts, timer interrupts, external interrupts (which are routed
via the platform level interrupt controller) and other per-HART
local interrupts.

We add a driver for the RISC-V local interrupt controller, which
eventually replaces the RISC-V architecture code, allowing for a
better split between arch code and drivers.

The driver is compliant with RISC-V Hart-Level Interrupt Controller
DT bindings located at:
Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt

Co-developed-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
[Palmer: Cleaned up warnings]
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>

The plic_find_hart_id() can be useful to other interrupt controller
drivers (such as RISC-V local interrupt driver) so we rename this
function to riscv_of_parent_hartid() and place it in arch directory
along with riscv_of_processor_hartid().

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Currently, the IPI handling routine riscv_software_interrupt() does
not take any argument and also does not perform irq_enter()/irq_exit().

This patch makes IPI handling routine more self-contained by:
1. Passing "pt_regs *" argument
2. Explicitly doing irq_enter()/irq_exit()
3. Explicitly save/restore "pt_regs *" using set_irq_regs()

With above changes, IPI handling routine does not depend on caller
function to perform irq_enter()/irq_exit() and save/restore of
"pt_regs *" hence its more self-contained. This also enables us
to call IPI handling routine from IRQCHIP drivers.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Like patch b1b3f49c ("ARM: config: sort select statements alphanumerically")
, we sort all our select statements alphanumerically by using the perl
script in patch b1b3f49c

 as above.

As suggested by Andrew Morton:

  This is a pet peeve of mine.  Any time there's a long list of items
  (header file inclusions, kconfig entries, array initalisers, etc) and
  someone wants to add a new item, they *always* go and stick it at the
  end of the list.

  Guys, don't do this.  Either put the new item into a randomly-chosen
  position or, probably better, alphanumerically sort the list.

Suggested-by: Zong Li <zong.li@sifive.com>
[Palmer: Re-ran the script, as there were predictably a bunch of conflicts]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

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

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
  ...

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

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
  ...

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
  ...

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
  ...

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
  ...

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
...

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 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
  ...

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>