Pull dmaengine updates from Vinod Koul:
 "This includes a new driver, removes R-Mobile APE6 as it is no longer
  used, sprd cyclic dma support, last batch of dma_slave_config
  direction removal and random updates to bunch of drivers.

  Summary:
   - New driver for UniPhier MIO DMA controller
   - Remove R-Mobile APE6 support
   - Sprd driver updates and support for cyclic link-list
   - Remove dma_slave_config direction usage from rest of drivers
   - Minor updates to dmatest, dw-dmac, zynqmp and bcm dma drivers"

* tag 'dmaengine-4.21-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (48 commits)
  dmaengine: qcom_hidma: convert to DEFINE_SHOW_ATTRIBUTE
  dmaengine: pxa: remove DBGFS_FUNC_DECL()
  dmaengine: mic_x100_dma: convert to DEFINE_SHOW_ATTRIBUTE
  dmaengine: amba-pl08x: convert to DEFINE_SHOW_ATTRIBUTE
  dmaengine: Documentation: Add documentation for multi chan testing
  dmaengine: dmatest: Add transfer_size parameter
  dmaengine: dmatest: Add alignment parameter
  dmaengine: dmatest: Use fixed point div to calculate iops
  dmaengine: dmatest: Add support for multi channel testing
  dmaengine: rcar-dmac: Document R8A774C0 bindings
  dt-bindings: dmaengine: usb-dmac: Add binding for r8a774c0
  dmaengine: zynqmp_dma: replace spin_lock_bh with spin_lock_irqsave
  dmaengine: sprd: Add me as one of the module authors
  dmaengine: sprd: Support DMA 2-stage transfer mode
  dmaengine: sprd: Support DMA link-list cyclic callback
  dmaengine: sprd: Set cur_desc as NULL when free or terminate one dma channel
  dmaengine: sprd: Fix the last link-list configuration
  dmaengine: sprd: Get transfer residue depending on the transfer direction
  dmaengine: sprd: Remove direction usage from struct dma_slave_config
  dmaengine: dmatest: fix a small memory leak in dmatest_func()
  ...

Pull kgdb updates from Daniel Thompson:
 "Mostly clean ups although while Doug's was chasing down a odd lockdep
  warning he also did some work to improved debugger resilience when
  some CPUs fail to respond to the round up request.

  The main changes are:

   - Fixing a lockdep warning on architectures that cannot use an NMI
     for the round up plus related changes to make CPU round up and all
     CPU backtrace more resilient.

   - Constify the arch ops tables

   - A couple of other small clean ups

  Two of the three patchsets here include changes that spill over into
  arch/. Changes in the arch space are relatively narrow in scope (and
  directly related to kgdb). Didn't get comprehensive acks but all
  impacted maintainers were Cc:ed in good time"

* tag 'kgdb-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops
  mips/kgdb: prepare arch_kgdb_ops for constness
  kdb: use bool for binary state indicators
  kdb: Don't back trace on a cpu that didn't round up
  kgdb: Don't round up a CPU that failed rounding up before
  kgdb: Fix kgdb_roundup_cpus() for arches who used smp_call_function()
  kgdb: Remove irq flags from roundup

Pull OpenRISC update from Stafford Horne:
 "Just one change for 4.21: Update comments for name change or32 -> or1k
  from Geert Uytterhoeven"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: Fix broken paths to arch/or32

Pull RTC updates from Alexandre Belloni:
 "Subsystem:
   - new %ptR printk format
   - rename core files
   - allow registration of multiple nvmem devices

  New driver:
   - i.MX system controller RTC

  Driver updates:
   - abx80x: handle voltage ioctls, correct binding doc
   - m41t80: correct month in alarm reads
   - pcf85363: add pcf85263 support
   - pcf8523: properly handle battery low flag
   - s3c: limit alarm to one year in the future as ALMYEAR is broken
   - sun6i: rework clock output binding"

* tag 'rtc-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (54 commits)
  rtc: rename core files
  rtc: nvmem: fix possible use after free
  rtc: add i.MX system controller RTC support
  dt-bindings: fsl: scu: add rtc binding
  rtc: pcf2123: Add Microcrystal rv2123
  rtc: class: reimplement devm_rtc_device_register
  rtc: enforce rtc_timer_init private_data type
  rtc: abx80x: Implement RTC_VL_READ,CLR ioctls
  rtc: pcf85363: Add support for NXP pcf85263 rtc
  dt-bindings: rtc: pcf85363: Document pcf85263 real-time clock
  rtc: pcf8523: don't return invalid date when battery is low
  dt-bindings: rtc: use a generic node name for ds1307
  PM: Switch to use %ptR
  m68k/mac: Switch to use %ptR
  Input: hp_sdc_rtc - Switch to use %ptR
  rtc: tegra: Switch to use %ptR
  rtc: s5m: Switch to use %ptR
  rtc: s3c: Switch to use %ptR
  rtc: rx8025: Switch to use %ptR
  rtc: rx6110: Switch to use %ptR
  ...

Pull pin control updates from Linus Walleij:
 "We have no core changes but lots of incremental development in drivers
  all over the place: Renesas, NXP, Mediatek and Actions Semiconductor
  keep churning out new SoCs.

  I have some subtree maintainers for Renesas and Intel helping out to
  keep down the load, it's been working smoothly (Samsung also have a
  subtree but it was not used this cycle.)

  New drivers:

   - NXP (ex Freescale) i.MX 8 QXP SoC driver.

   - Mediatek MT6797 SoC driver.

   - Mediatek MT7629 SoC driver.

   - Actions Semiconductor S700 SoC driver.

   - Renesas RZ/A2 SoC driver.

   - Allwinner sunxi suniv F1C100 SoC driver.

   - Qualcomm PMS405 PMIC driver.

   - Microsemi Ocelot Jaguar2 SoC driver.

  Improvements:

   - Some RT improvements (using raw spinlocks where appropriate).

   - A lot of new pin sets on the Renesas PFC pin controllers.

   - GPIO hogs now work on the Qualcomm SPMI/SSBI pin controller GPIO
     chips, and Xway.

   - Major modernization of the Intel pin control drivers.

   - STM32 pin control driver will now synchronize usage of pins with
     another CPU using a hardware spinlock"

* tag 'pinctrl-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (145 commits)
  dt-bindings: arm: fsl-scu: add imx8qm pinctrl support
  pinctrl: freescale: Break dependency on SOC_IMX8MQ for i.MX8MQ
  pinctrl: imx-scu: Depend on IMX_SCU
  pinctrl: ocelot: Add dependency on HAS_IOMEM
  pinctrl: ocelot: add MSCC Jaguar2 support
  pinctrl: bcm: ns: support updated DT binding as syscon subnode
  dt-bindings: pinctrl: bcm4708-pinmux: rework binding to use syscon
  MAINTAINERS: merge at91 pinctrl entries
  pinctrl: imx8qxp: break the dependency on SOC_IMX8QXP
  pinctrl: uniphier: constify uniphier_pinctrl_socdata
  pinctrl: mediatek: improve Kconfig dependencies
  pinctrl: msm: mark PM functions as __maybe_unused
  dt-bindings: pinctrl: sunxi: Add supply properties
  pinctrl: meson: meson8b: add the missing GPIO_GROUPs for BOOT and CARD
  pinctrl: meson: meson8: add the missing GPIO_GROUPs for BOOT and CARD
  pinctrl: meson: meson8: rename the "gpio" function to "gpio_periphs"
  pinctrl: meson: meson8: rename the "gpio" function to "gpio_periphs"
  pinctrl: meson: meson8b: fix the GPIO function for the GPIOAO pins
  pinctrl: meson: meson8: fix the GPIO function for the GPIOAO pins
  pinctrl: sh-pfc: Make pinmux_cfg_reg.var_field_width[] variable-length
  ...

Pull watchdog updates from Wim Van Sebroeck:
 - add TQ-Systems TQMX86 watchdog driver
 - add Qualcomm PM8916 watchdog driver
 - w83627hf_wdt: add quirk for Inves system
 - renesas_wdt: several improvements and document r8a774c0 support
 - mena21_wdt, mtx-1: Convert to use GPIO descriptor
 - bcm281xx, ie6xx_wdt: convert to DEFINE_SHOW_ATTRIBUTE
 - documentation: add PM usage and kernel-api: don't reference removed functions
 - update bindings for MT7629 SoC
 - several small fixes

* tag 'linux-watchdog-4.21-rc1' of git://www.linux-watchdog.org/linux-watchdog: (22 commits)
  watchdog: tqmx86: Add watchdog driver for the IO controller
  dt-bindings: watchdog: renesas-wdt: Document r8a774c0 support
  watchdog: docs: kernel-api: don't reference removed functions
  watchdog: add documentation for PM usage
  watchdog: mtx-1: Convert to use GPIO descriptor
  watchdog: mena21_wdt: Convert to GPIO descriptors
  dt-bindings: watchdog: Add Qualcomm PM8916 watchdog
  watchdog: Add pm8916 watchdog driver
  dt-bindings: watchdog: update bindings for MT7629 SoC
  watchdog: renesas_wdt: don't keep timer value during suspend/resume
  watchdog: ie6xx_wdt: convert to DEFINE_SHOW_ATTRIBUTE
  watchdog: bcm281xx: convert to DEFINE_SHOW_ATTRIBUTE
  watchdog: asm9260_wdt: make array mode_name static, shrinks object size
  watchdog/hpwdt: Update driver version.
  watchdog/hpwdt: Do not claim unsupported hardware
  watchdog/hpwdt: Exclude via blacklist
  Watchdog: remove outdated comment
  watchdog: w83627hf_wdt: Add quirk for Inves system
  watchdog: cpwd: add of_node_put()
  watchdog: renesas_wdt: don't set divider while watchdog is running
  ...

We need to check the return value of match_token() for Opt_err before
doing anything with it.

[ Not only did the old "-1" value for Opt_err cause problems for the
  __test_and_set_bit(), as fixed in commit 94c13f66 ("security:
  don't use a negative Opt_err token index"), but accessing
  "args[0].from" is invalid for the Opt_err case, as pointed out by Eric
  later.  - Linus ]

Reported-by: syzbot+a22e0dc07567662c50bc@syzkaller.appspotmail.com
Fixes: 00d60fd3 ("KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: stable@kernel.org # 4.20
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM SoC defconfig updates from Olof Johansson:
 "Most changes here are to enable new drivers and platforms in the
  various configs that affect them. Most of these have been covered and
  described in the other branches, we mostly keep defconfig separate to
  avoid conflicts between SoC/dt/driver updates that they otherwise
  would be grouped with.

  One thing worth mentioning here is that OMAP changes from using their
  own UART driver, to 8250, for the multi_v7_defconfig shared config on
  32-bit. This means that the console is now named ttyS* instead of
  ttyO*. This change was already done for omap2_defconfig a while back,
  so most users of these configs have either already updated, or can
  easily follow the same patterns as they did at that time. This makes
  platform support slightly easier for distros, since they no longer
  need to keep track of a separate console prefix for these platforms"

* tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (31 commits)
  Revert "arm64: defconfig: Enable FSL_MC_BUS and FSL_MC_DPIO"
  arm64: defconfig: Enable FSL_MC_BUS and FSL_MC_DPIO
  arm64: defconfig: Replace PINCTRL_MT7622 with PINCTRL_MTK_MOORE
  arm64: defconfig: Regenerate for v4.20
  ARM: multi_v7_defconfig: Add TOSHIBA TC358764 bridge driver
  ARM: multi_v7_defconfig: Add MAX8952 regulator driver
  ARM: exynos_defconfig: Add TOSHIBA TC358764 bridge driver
  ARM: exynos_defconfig: Add MAX8952 regulator driver
  ARM: exynos_defconfig: Add MAX8998 RTC and charger drivers
  ARM: imx_v6_v7_defconfig: add imx7ulp support
  ARM: imx_v6_v7_defconfig: Select TOUCHSCREEN_GOODIX
  ARM: multi_v7_defconfig: enable STM32 analog & timer drivers
  arm64: defconfig: Enable GCC and PINCTRL for MSM8998
  arm64: defconfig: Enable core Qualcomm SDM845 options
  ARM: defconfig: Enable the PL111 DRM driver on vexpress
  ARM: defconfig: Update the vexpress defconfig
  arm64: defconfig: Enable some qcom remoteproc configs
  arm64: defconfig: Enable QCS404 configs
  ARM: imx_v6_v7_defconfig: Enable USB_ANNOUNCE_NEW_DEVICES
  ARM: imx_v6_v7_defconfig: Enable BT_BNEP
  ...

Pull ARM Device-tree updates from Olof Johansson:
 "As usual, this is where the bulk of our changes end up landing each
  merge window.

  The individual updates are too many to enumerate, many many platforms
  have seen additions of device descriptions such that they are
  functionally more complete (in fact, this is often the bulk of updates
  we see).

  Instead I've mostly focused on highlighting the new platforms below as
  they are introduced. Sometimes the introduction is of mostly a
  fragment, that later gets filled in on later releases, and in some
  cases it's near-complete platform support. The latter is more common
  for derivative platforms that already has similar support in-tree.

  Two SoCs are slight outliers from the usual range of additions.
  Allwinner support for F1C100s, a quite old SoC (ARMv5-based) shipping
  in the Lychee Pi Nano platform. At the other end is NXP Layerscape
  LX2160A, a 16-core 2.2GHz Cortex-A72 SoC with a large amount of I/O
  aimed at infrastructure/networking.

  TI updates stick out in the diff stats too, in particular because they
  have moved the description of their L4 on-chip interconnect to
  devicetree, which opens up for removal of even more of their
  platform-specific 'hwmod' description tables over the next few
  releases.

  SoCs:
   - Qualcomm QCS404 (4x Cortex-A53)
   - Allwinner T3 (rebranded R40) and f1c100s (armv5)
   - NXP i.MX7ULP (1x Cortex-A7 + 1x Cortex-M4)
   - NXP LS1028A (2x Cortex-A72), LX2160A (16x Cortex-A72)

  New platforms:
   - Rockchip: Gru Scarlet (RK3188 Tablet)
   - Amlogic: Phicomm N1 (S905D), Libretech S805-AC
   - Broadcom: Linksys EA6500 v2 Wi-Fi router (BCM4708)
   - Qualcomm: QCS404 base platform and EVB
   - Qualcomm: Remove of Arrow SD600
   - PXA: First PXA3xx DT board: Raumfeld
   - Aspeed: Facebook Backpack-CMM BMC
   - Renesas iWave G20D-Q7 (RZ/G1N)
   - Allwinner t3-cqa3t-bv3 (T3/R40) and Lichee Pi Nano (F1C100s)
   - Allwinner Emlid Neutis N5, Mapleboard MP130
   - Marvell Macchiatobin Single Shot (Armada 8040, no 10GbE)
   - i.MX: mtrion emCON-MX6, imx6ul-pico-pi, imx7d-sdb-reva
   - VF610: Liebherr's BK4 device, ZII SCU4 AIB board
   - i.MX7D PICO Hobbit baseboard
   - i.MX7ULP EVK board
   - NXP LX2160AQDS and LX2160ARDB boards

  Other:
   - Coresight binding updates across the board
   - CPU cooling maps updates across the board"

* tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (648 commits)
  ARM: dts: suniv: Fix improper bindings include patch
  ARM: dts: sunxi: Enable Broadcom-based Bluetooth for multiple boards
  arm64: dts: allwinner: a64: bananapi-m64: Add Bluetooth device node
  ARM: dts: suniv: Fix improper bindings include patch
  arm64: dts: Add spi-[tx/rx]-bus-width for the FSL QSPI controller
  arm64: dts: Remove unused properties from FSL QSPI driver nodes
  ARM: dts: Add spi-[tx/rx]-bus-width for the FSL QSPI controller
  ARM: dts: imx6sx-sdb: Fix the reg properties for the FSL QSPI nodes
  ARM: dts: Remove unused properties from FSL QSPI driver nodes
  arm64: dts: ti: k3-am654: Enable main domain McSPI0
  arm64: dts: ti: k3-am654: Add McSPI DT nodes
  arm64: dts: ti: k3-am654: Populate power-domain property for UART nodes
  arm64: dts: ti: k3-am654-base-board: Enable ECAP PWM
  arm64: dts: ti: k3-am65-main: Add ECAP PWM node
  arm64: dts: ti: k3-am654-base-board: Add I2C nodes
  arm64: dts: ti: am654-base-board: Add pinmux for main uart0
  arm64: dts: ti: k3-am65: Add pinctrl regions
  dt-bindings: pinctrl: k3: Introduce pinmux definitions
  ARM: dts: exynos: Specify I2S assigned clocks in proper node
  ARM: dts: exynos: Add missing CPUs in cooling maps for Odroid X2
  ...

Pull ARM SoC driver updates from Olof Johansson:
 "Misc driver updates for platforms, many of them power related.

   - Rockchip adds power domain support for rk3066 and rk3188

   - Amlogic adds a power measurement driver

   - Allwinner adds SRAM support for three platforms (F1C100, H5, A64
     C1)

   - Wakeup and ti-sysc (platform bus) fixes for OMAP/DRA7

   - Broadcom fixes suspend/resume with Thumb2 kernels, and improves
     stability of a handful of firmware/platform interfaces

   - PXA completes their conversion to dmaengine framework

   - Renesas does a bunch of PM cleanups across many platforms

   - Tegra adds support for suspend/resume on T186/T194, which includes
     some driver cleanups and addition of wake events

   - Tegra also adds a driver for memory controller (EMC) on Tegra2

   - i.MX tweaks power domain bindings, and adds support for i.MX8MQ in
     GPC

   - Atmel adds identifiers and LPDDR2 support for a new SoC, SAM9X60

  and misc cleanups across several platforms"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (73 commits)
  ARM: at91: add support in soc driver for new SAM9X60
  ARM: at91: add support in soc driver for LPDDR2 SiP
  memory: omap-gpmc: Use of_node_name_eq for node name comparisons
  bus: ti-sysc: Check for no-reset and no-idle flags at the child level
  ARM: OMAP2+: Check also the first dts child for hwmod flags
  soc: amlogic: meson-clk-measure: Add missing REGMAP_MMIO dependency
  soc: imx: gpc: Increase GPC_CLK_MAX to 7
  soc: renesas: rcar-sysc: Fix power domain control after system resume
  soc: renesas: rcar-sysc: Merge PM Domain registration and linking
  soc: renesas: rcar-sysc: Remove rcar_sysc_power_{down,up}() helpers
  soc: renesas: r8a77990-sysc: Fix initialization order of 3DG-{A,B}
  dt-bindings: sram: sunxi: Add compatible for the A64 SRAM C1
  dt-bindings: sram: sunxi: Add bindings for the H5 with SRAM C1
  dt-bindings: sram: Add Allwinner suniv F1C100s
  soc: sunxi: sram: Add support for the H5 SoC system control
  soc: sunxi: sram: Enable EMAC clock access for H3 variant
  soc: imx: gpcv2: add support for i.MX8MQ SoC
  soc: imx: gpcv2: move register access table to domain data
  soc: imx: gpcv2: prefix i.MX7 specific defines
  dmaengine: pxa: make the filter function internal
  ...

Pull arm SoC platform updates from Olof Johansson:
 "SoC updates, mostly refactorings and cleanups of old legacy platforms,
  but also a few more things:

  New SoC support this release:
   - NXP/Freescale i.MX7ULP (1x Cortex-A7, Cortex-M4, graphics, etc)
   - Allwinner F1C100, older platform with an ARM926-EJS (ARMv5) core

  Cleanups of various platforms:
   - OMAP1 ams-delta does some GPIO cleanups
   - Davinci removes of at24 platform data
   - Samsung cleans up old wakeup, PM debug and secondary core boot code
   - Renesas moves around config options and PM code to drivers/soc for
     sharing with 64-bit and more consistency
   - i.MX, Broadcom and SoCFPGA all have tweaks to lowlevel debug
     console setups
   - SoCFPGA adds explicit selection of ARM errata and removes some
     unused code

  This also contains a few patches that I had queued up as fixes for
  4.20 but didn't send in before the release"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (68 commits)
  arm64: dts: renesas: draak: Fix CVBS input
  ARM: omap2: avoid section mismatch warning
  ARM: tegra: avoid section mismatch warning
  ARM: ks8695: fix section mismatch warning
  ARM: pxa: avoid section mismatch warning
  ARM: mmp: fix pxa168_device_usb_phy use on aspenite
  ARM: mmp: fix timer_init calls
  ARM: OMAP1: fix USB configuration for device-only setups
  ARM: OMAP1: add MMC configuration for Palm Tungsten E
  ARM: imx: fix dependencies on imx7ulp
  ARM: meson: select HAVE_ARM_TWD and ARM_GLOBAL_TIMER
  MAINTAINERS: add drivers/soc/amlogic/ to amlogic list
  ARM: imx: add initial support for imx7ulp
  ARM: debug-imx: only define DEBUG_IMX_UART_PORT if needed
  ARM: dts: Fix OMAP4430 SDP Ethernet startup
  ARM: dts: am335x-pdu001: Fix polarity of card detection input
  ARM: OMAP1: ams-delta: Fix audio permanently muted
  ARM: dts: omap5: Fix dual-role mode on Super-Speed port
  arm64: dts: rockchip: fix rk3399-rockpro64 regulator gpios
  ARM: davinci: da850-evm: remove unnecessary include
  ...

Merge in fixes here, since the last batch didn't make it in before the
release of 4.20, and we might as well group them with this set of
patches.

* fixes: (822 commits)
  arm64: dts: renesas: draak: Fix CVBS input
  ARM: dts: Fix OMAP4430 SDP Ethernet startup
  ARM: dts: am335x-pdu001: Fix polarity of card detection input
  ARM: OMAP1: ams-delta: Fix audio permanently muted
  ARM: dts: omap5: Fix dual-role mode on Super-Speed port
  arm64: dts: rockchip: fix rk3399-rockpro64 regulator gpios
  ARM: dts: imx7d-nitrogen7: Fix the description of the Wifi clock
  ARM: imx: update the cpu power up timing setting on i.mx6sx
  Revert "arm64: dts: marvell: add CPU Idle power state support on Armada 7K/8K"
  ARM: dts: imx7d-pico: Describe the Wifi clock
  ARM: dts: realview: Fix some more duplicate regulator nodes
  MAINTAINERS: update entry for MMP platform
  ARM: mmp/mmp2: fix cpu_is_mmp2() on mmp2-dt
  MAINTAINERS: mediatek: Update SoC entry
  ARM: dts: bcm2837: Fix polarity of wifi reset GPIOs
  + Linux 4.20-rc5
Signed-off-by: Olof Johansson <olof@lixom.net>

Pull tracing updates from Steven Rostedt:

 - Rework of the kprobe/uprobe and synthetic events to consolidate all
   the dynamic event code. This will make changes in the future easier.

 - Partial rewrite of the function graph tracing infrastructure. This
   will allow for multiple users of hooking onto functions to get the
   callback (return) of the function. This is the ground work for having
   kprobes and function graph tracer using one code base.

 - Clean up of the histogram code that will facilitate adding more
   features to the histograms in the future.

 - Addition of str_has_prefix() and a few use cases. There currently is
   a similar function strstart() that is used in a few places, but only
   returns a bool and not a length. These instances will be removed in
   the future to use str_has_prefix() instead.

 - A few other various clean ups as well.

* tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
  tracing: Use the return of str_has_prefix() to remove open coded numbers
  tracing: Have the historgram use the result of str_has_prefix() for len of prefix
  tracing: Use str_has_prefix() instead of using fixed sizes
  tracing: Use str_has_prefix() helper for histogram code
  string.h: Add str_has_prefix() helper function
  tracing: Make function ‘ftrace_exports’ static
  tracing: Simplify printf'ing in seq_print_sym
  tracing: Avoid -Wformat-nonliteral warning
  tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
  tracing: Add hist trigger comments for variable-related fields
  tracing: Remove hist trigger synth_var_refs
  tracing: Use hist trigger's var_ref array to destroy var_refs
  tracing: Remove open-coding of hist trigger var_ref management
  tracing: Use var_refs[] for hist trigger reference checking
  tracing: Change strlen to sizeof for hist trigger static strings
  tracing: Remove unnecessary hist trigger struct field
  tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
  seq_buf: Use size_t for len in seq_buf_puts()
  seq_buf: Make seq_buf_puts() null-terminate the buffer
  arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
  ...

Pull alpha architecture updates from Matt Turner:
 "A few small changes for alpha as well as the new system call table
  generation support from Firoz Khan"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha:
  alpha: Remove some unused variables
  alpha: rtc: simplify alpha_rtc_init
  alpha: Fix a typo on ptrace.h
  alpha: fix spelling mistake QSD_PORT_ACTUVE -> QSD_PORT_ACTIVE
  alpha: generate uapi header and syscall table header files
  alpha: add system call table generation support
  alpha: add __NR_syscalls along with NR_SYSCALLS
  alpha: remove CONFIG_OSF4_COMPAT flag from syscall table
  alpha: move __IGNORE* entries to non uapi header

Pull scheduler fix from Ingo Molnar:
 "This is a revert for a lockup in cgroups-intense workloads - the real
  fixes will come later"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f654

Pull dax fix from Dan Williams:
 "Clean up unnecessary usage of prepare_to_wait_exclusive().

  While I feel a bit silly sending a single-commit pull-request there is
  nothing else queued up for dax this cycle. This change has shipped in
  -next for multiple releases"

* tag 'dax-fix-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Use non-exclusive wait in wait_entry_unlocked()

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've focused on bug fixes since Pixel devices have
  been shipping with f2fs. Some of them were related to hardware
  encryption support which are actually not an issue in mainline, but
  would be better to merge them in order to avoid potential bugs.

  Enhancements:
   - do GC sub-sections when the section is large
   - add a flag in ioctl(SHUTDOWN) to trigger fsck for QA
   - use kvmalloc() in order to give another chance to avoid ENOMEM

  Bug fixes:
   - fix accessing memory boundaries in a malformed iamge
   - GC gives stale unencrypted block
   - GC counts in large sections
   - detect idle time more precisely
   - block allocation of DIO writes
   - race conditions between write_begin and write_checkpoint
   - allow GCs for node segments via ioctl()

  There are various clean-ups and minor bug fixes as well"

* tag 'f2fs-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (43 commits)
  f2fs: sanity check of xattr entry size
  f2fs: fix use-after-free issue when accessing sbi->stat_info
  f2fs: check PageWriteback flag for ordered case
  f2fs: fix validation of the block count in sanity_check_raw_super
  f2fs: fix missing unlock(sbi->gc_mutex)
  f2fs: fix to dirty inode synchronously
  f2fs: clean up structure extent_node
  f2fs: fix block address for __check_sit_bitmap
  f2fs: fix sbi->extent_list corruption issue
  f2fs: clean up checkpoint flow
  f2fs: flush stale issued discard candidates
  f2fs: correct wrong spelling, issing_*
  f2fs: use kvmalloc, if kmalloc is failed
  f2fs: remove redundant comment of unused wio_mutex
  f2fs: fix to reorder set_page_dirty and wait_on_page_writeback
  f2fs: clear PG_writeback if IPU failed
  f2fs: add an ioctl() to explicitly trigger fsck later
  f2fs: avoid frequent costly fsck triggers
  f2fs: fix m_may_create to make OPU DIO write correctly
  f2fs: fix to update new block address correctly for OPU
  ...

Rename core files so there is a clearer separation between the RTC core and
the RTC drivers.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

In cas of probe failure, devres may free the memory allocated for
rtc->nvram before devm_rtc_release_device() is called. This leads to
rtc_nvram_unregister using it after being freed which may lead to a crash.

This has been shown to happen after commit 461e557b ("rtc: nvmem: use
devm_nvmem_register()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Zhipeng Xie, Xie XiuQi and Sargun Dhillon reported lockups in the
scheduler under high loads, starting at around the v4.18 time frame,
and Zhipeng Xie tracked it down to bugs in the rq->leaf_cfs_rq_list
manipulation.

Do a (manual) revert of:

  a9e7f654 ("sched/fair: Fix O(nr_cgroups) in load balance path")

It turns out that the list_del_leaf_cfs_rq() introduced by this commit
is a surprising property that was not considered in followup commits
such as:

  9c2791f9 ("sched/fair: Fix hierarchical order in rq->leaf_cfs_rq_list")

As Vincent Guittot explains:

 "I think that there is a bigger problem with commit a9e7f654 and
  cfs_rq throttling:

  Let take the example of the following topology TG2 --> TG1 --> root:

   1) The 1st time a task is enqueued, we will add TG2 cfs_rq then TG1
      cfs_rq to leaf_cfs_rq_list and we are sure to do the whole branch in
      one path because it has never been used and can't be throttled so
      tmp_alone_branch will point to leaf_cfs_rq_list at the end.

   2) Then TG1 is throttled

   3) and we add TG3 as a new child of TG1.

   4) The 1st enqueue of a task on TG3 will add TG3 cfs_rq just before TG1
      cfs_rq and tmp_alone_branch will stay  on rq->leaf_cfs_rq_list.

  With commit a9e7f654, we can del a cfs_rq from rq->leaf_cfs_rq_list.
  So if the load of TG1 cfs_rq becomes NULL before step 2) above, TG1
  cfs_rq is removed from the list.
  Then at step 4), TG3 cfs_rq is added at the beginning of rq->leaf_cfs_rq_list
  but tmp_alone_branch still points to TG3 cfs_rq because its throttled
  parent can't be enqueued when the lock is released.
  tmp_alone_branch doesn't point to rq->leaf_cfs_rq_list whereas it should.

  So if TG3 cfs_rq is removed or destroyed before tmp_alone_branch
  points on another TG cfs_rq, the next TG cfs_rq that will be added,
  will be linked outside rq->leaf_cfs_rq_list - which is bad.

  In addition, we can break the ordering of the cfs_rq in
  rq->leaf_cfs_rq_list but this ordering is used to update and
  propagate the update from leaf down to root."

Instead of trying to work through all these cases and trying to reproduce
the very high loads that produced the lockup to begin with, simplify
the code temporarily by reverting a9e7f654 - which change was clearly
not thought through completely.

This (hopefully) gives us a kernel that doesn't lock up so people
can continue to enjoy their holidays without worrying about regressions. ;-)

[ mingo: Wrote changelog, fixed weird spelling in code comment while at it. ]
Analyzed-by: Xie XiuQi <xiexiuqi@huawei.com>
Analyzed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reported-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Reported-by: Sargun Dhillon <sargun@sargun.me>
Reported-by: Xie XiuQi <xiexiuqi@huawei.com>
Tested-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Tested-by: Sargun Dhillon <sargun@sargun.me>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: <stable@vger.kernel.org> # v4.13+
Cc: Bin Li <huawei.libin@huawei.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a9e7f654 ("sched/fair: Fix O(nr_cgroups) in load balance path")
Link: http://lkml.kernel.org/r/1545879866-27809-1-git-send-email-xiexiuqi@huawei.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

checkpatch.pl reports the following:

  WARNING: struct kgdb_arch should normally be const
  #28: FILE: arch/mips/kernel/kgdb.c:397:
  +struct kgdb_arch arch_kgdb_ops = {

This report makes sense, as all other ops struct, this
one should also be const. This patch does the change.

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

MIPS is the only architecture modifying arch_kgdb_ops during init.
This patch makes the init static, so that it can be changed to
const in following patch, as recommended by checkpatch.pl
Suggested-by: Paul Burton <paul.burton@mips.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

defcmd_in_progress  is the state trace for command group processing
- within a command group or not -  usable  is an indicator if a command
set is valid (allocated/non-empty) - so use a bool for those binary
indication here.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

If you have a CPU that fails to round up and then run 'btc' you'll end
up crashing in kdb becaue we dereferenced NULL.  Let's add a check.
It's wise to also set the task to NULL when leaving the debugger so
that if we fail to round up on a later entry into the debugger we
won't backtrace a stale task.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

If we're using the default implementation of kgdb_roundup_cpus() that
uses smp_call_function_single_async() we can end up hanging
kgdb_roundup_cpus() if we try to round up a CPU that failed to round
up before.

Specifically smp_call_function_single_async() will try to wait on the
csd lock for the CPU that we're trying to round up.  If the previous
round up never finished then that lock could still be held and we'll
just sit there hanging.

There's not a lot of use trying to round up a CPU that failed to round
up before.  Let's keep a flag that indicates whether the CPU started
but didn't finish to round up before.  If we see that flag set then
we'll skip the next round up.

In general we have a few goals here:
- We never want to end up calling smp_call_function_single_async()
  when the csd is still locked.  This is accomplished because
  flush_smp_call_function_queue() unlocks the csd _before_ invoking
  the callback.  That means that when kgdb_nmicallback() runs we know
  for sure the the csd is no longer locked.  Thus when we set
  "rounding_up = false" we know for sure that the csd is unlocked.
- If there are no timeouts rounding up we should never skip a round
  up.

NOTE #1: In general trying to continue running after failing to round
up CPUs doesn't appear to be supported in the debugger.  When I
simulate this I find that kdb reports "Catastrophic error detected"
when I try to continue.  I can overrule and continue anyway, but it
should be noted that we may be entering the land of dragons here.
Possibly the "Catastrophic error detected" was added _because_ of the
future failure to round up, but even so this is an area of the code
that hasn't been strongly tested.

NOTE #2: I did a bit of testing before and after this change.  I
introduced a 10 second hang in the kernel while holding a spinlock
that I could invoke on a certain CPU with 'taskset -c 3 cat /sys/...".

Before this change if I did:
- Invoke hang
- Enter debugger
- g (which warns about Catastrophic error, g again to go anyway)
- g
- Enter debugger

...I'd hang the rest of the 10 seconds without getting a debugger
prompt.  After this change I end up in the debugger the 2nd time after
only 1 second with the standard warning about 'Timed out waiting for
secondary CPUs.'

I'll also note that once the CPU finished waiting I could actually
debug it (aka "btc" worked)

I won't promise that everything works perfectly if the errant CPU
comes back at just the wrong time (like as we're entering or exiting
the debugger) but it certainly seems like an improvement.

NOTE #3: setting 'kgdb_info[cpu].rounding_up = false' is in
kgdb_nmicallback() instead of kgdb_call_nmi_hook() because some
implementations override kgdb_call_nmi_hook().  It shouldn't hurt to
have it in kgdb_nmicallback() in any case.

NOTE #4: this logic is really only needed because there is no API call
like "smp_try_call_function_single_async()" or "smp_csd_is_locked()".
If such an API existed then we'd use it instead, but it seemed a bit
much to add an API like this just for kgdb.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

When I had lockdep turned on and dropped into kgdb I got a nice splat
on my system.  Specifically it hit:
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)

Specifically it looked like this:
  sysrq: SysRq : DEBUG
  ------------[ cut here ]------------
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)
  WARNING: CPU: 0 PID: 0 at .../kernel/locking/lockdep.c:2875 lockdep_hardirqs_on+0xf0/0x160
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.0 #27
  pstate: 604003c9 (nZCv DAIF +PAN -UAO)
  pc : lockdep_hardirqs_on+0xf0/0x160
  ...
  Call trace:
   lockdep_hardirqs_on+0xf0/0x160
   trace_hardirqs_on+0x188/0x1ac
   kgdb_roundup_cpus+0x14/0x3c
   kgdb_cpu_enter+0x53c/0x5cc
   kgdb_handle_exception+0x180/0x1d4
   kgdb_compiled_brk_fn+0x30/0x3c
   brk_handler+0x134/0x178
   do_debug_exception+0xfc/0x178
   el1_dbg+0x18/0x78
   kgdb_breakpoint+0x34/0x58
   sysrq_handle_dbg+0x54/0x5c
   __handle_sysrq+0x114/0x21c
   handle_sysrq+0x30/0x3c
   qcom_geni_serial_isr+0x2dc/0x30c
  ...
  ...
  irq event stamp: ...45
  hardirqs last  enabled at (...44): [...] __do_softirq+0xd8/0x4e4
  hardirqs last disabled at (...45): [...] el1_irq+0x74/0x130
  softirqs last  enabled at (...42): [...] _local_bh_enable+0x2c/0x34
  softirqs last disabled at (...43): [...] irq_exit+0xa8/0x100
  ---[ end trace adf21f830c46e638 ]---

Looking closely at it, it seems like a really bad idea to be calling
local_irq_enable() in kgdb_roundup_cpus().  If nothing else that seems
like it could violate spinlock semantics and cause a deadlock.

Instead, let's use a private csd alongside
smp_call_function_single_async() to round up the other CPUs.  Using
smp_call_function_single_async() doesn't require interrupts to be
enabled so we can remove the offending bit of code.

In order to avoid duplicating this across all the architectures that
use the default kgdb_roundup_cpus(), we'll add a "weak" implementation
to debug_core.c.

Looking at all the people who previously had copies of this code,
there were a few variants.  I've attempted to keep the variants
working like they used to.  Specifically:
* For arch/arc we passed NULL to kgdb_nmicallback() instead of
  get_irq_regs().
* For arch/mips there was a bit of extra code around
  kgdb_nmicallback()

NOTE: In this patch we will still get into trouble if we try to round
up a CPU that failed to round up before.  We'll try to round it up
again and potentially hang when we try to grab the csd lock.  That's
not new behavior but we'll still try to do better in a future patch.
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

The function kgdb_roundup_cpus() was passed a parameter that was
documented as:

> the flags that will be used when restoring the interrupts. There is
> local_irq_save() call before kgdb_roundup_cpus().

Nobody used those flags.  Anyone who wanted to temporarily turn on
interrupts just did local_irq_enable() and local_irq_disable() without
looking at them.  So we can definitely remove the flags.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>