Commit Graph

1221 Commits

Author SHA1 Message Date
Waiman Long
a33fda35e3 locking/qspinlock: Introduce a simple generic 4-byte queued spinlock
This patch introduces a new generic queued spinlock implementation that
can serve as an alternative to the default ticket spinlock. Compared
with the ticket spinlock, this queued spinlock should be almost as fair
as the ticket spinlock. It has about the same speed in single-thread
and it can be much faster in high contention situations especially when
the spinlock is embedded within the data structure to be protected.

Only in light to moderate contention where the average queue depth
is around 1-3 will this queued spinlock be potentially a bit slower
due to the higher slowpath overhead.

This queued spinlock is especially suit to NUMA machines with a large
number of cores as the chance of spinlock contention is much higher
in those machines. The cost of contention is also higher because of
slower inter-node memory traffic.

Due to the fact that spinlocks are acquired with preemption disabled,
the process will not be migrated to another CPU while it is trying
to get a spinlock. Ignoring interrupt handling, a CPU can only be
contending in one spinlock at any one time. Counting soft IRQ, hard
IRQ and NMI, a CPU can only have a maximum of 4 concurrent lock waiting
activities.  By allocating a set of per-cpu queue nodes and used them
to form a waiting queue, we can encode the queue node address into a
much smaller 24-bit size (including CPU number and queue node index)
leaving one byte for the lock.

Please note that the queue node is only needed when waiting for the
lock. Once the lock is acquired, the queue node can be released to
be used later.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:25 +02:00
Linus Torvalds
41d5e08ea8 TTY/Serial patches for 4.1-rc1
Here's the big tty/serial driver update for 4.1-rc1.
 
 It was delayed for a bit due to some questions surrounding some of the
 console command line parsing changes that are in here.  There's still
 one tiny regression for people who were previously putting multiple
 console command lines and expecting them all to be ignored for some odd
 reason, but Peter is working on fixing that.  If not, I'll send a revert
 for the offending patch, but I have faith that Peter can address it.
 
 Other than the console work here, there's the usual serial driver
 updates and changes, and a buch of 8250 reworks to try to make that
 driver easier to maintain over time, and have it support more devices in
 the future.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver update for 4.1-rc1.

  It was delayed for a bit due to some questions surrounding some of the
  console command line parsing changes that are in here.  There's still
  one tiny regression for people who were previously putting multiple
  console command lines and expecting them all to be ignored for some
  odd reason, but Peter is working on fixing that.  If not, I'll send a
  revert for the offending patch, but I have faith that Peter can
  address it.

  Other than the console work here, there's the usual serial driver
  updates and changes, and a buch of 8250 reworks to try to make that
  driver easier to maintain over time, and have it support more devices
  in the future.

  All of these have been in linux-next for a while"

* tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
  n_gsm: Drop unneeded cast on netdev_priv
  sc16is7xx: expose RTS inversion in RS-485 mode
  serial: 8250_pci: port failed after wakeup from S3
  earlycon: 8250: Document kernel command line options
  earlycon: 8250: Fix command line regression
  earlycon: Fix __earlycon_table stride
  tty: clean up the tty time logic a bit
  serial: 8250_dw: only get the clock rate in one place
  serial: 8250_dw: remove useless ACPI ID check
  dmaengine: hsu: move memory allocation to GFP_NOWAIT
  dmaengine: hsu: remove redundant pieces of code
  serial: 8250_pci: add Intel Tangier support
  dmaengine: hsu: add Intel Tangier PCI ID
  serial: 8250_pci: replace switch-case by formula for Intel MID
  serial: 8250_pci: replace switch-case by formula
  tty: cpm_uart: replace CONFIG_8xx by CONFIG_CPM1
  serial: jsm: some off by one bugs
  serial: xuartps: Fix check in console_setup().
  serial: xuartps: Get rid of register access macros.
  serial: xuartps: Fix iobase use.
  ...
2015-04-21 09:33:10 -07:00
Linus Torvalds
510965dd4a This is the bulk of GPIO changes for the v4.1 development
cycle:
 
 - A new GPIO hogging mechanism has been added. This can
   be used on boards that want to drive some GPIO line high,
   low, or set it as input on boot and then never touch it
   again. For some embedded systems this is bliss and
   simplifies things to a great extent.
 
 - Some API cleanup and closure: gpiod_get_array() and
   gpiod_put_array() has been added to get and put GPIOs
   in bulk as was possible with the non-descriptor API.
 
 - Encapsulate cross-calls to the pin control subsystem in
   <linux/gpio/driver.h>. Now this should be the only header
   any GPIO driver needs to include or something is wrong.
   Cleanups restricting drivers to this include are welcomed
   if tested.
 
 - Sort the GPIO Kconfig and split it into submenus, as
   it was becoming and unstructured, illogical and
   unnavigatable mess. I hope this is easier to follow.
   Menus that require a certain subsystem like I2C can
   now be hidden nicely for example, still working on
   others.
 
 - New drivers:
 
     - New driver for the Altera Soft GPIO.
 
     - The F7188x driver now handles the F71869 and
       F71869A variants.
 
     - The MIPS Loongson driver has been moved to
       drivers/gpio for consolidation and cleanup.
 
 - Cleanups:
 
    - The MAX732x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - The PCF857x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - Radical cleanup of the OMAP driver.
 
 - Misc:
 
    - Enable the DWAPB GPIO for all architectures. This is
      a "hard IP" block from Synopsys which has started to
      turn up in so diverse architectures as X86 Quark, ARC
      and a slew of ARM systems. So even though it's not an
      expander, it's generic enough to be available for all.
 
    - We add a mock GPIO on Crystalcove PMIC after a long
      discussion with Daniel Vetter et al, tracing back to
      the shootout at the kernel summit where DRM drivers
      and sub-componentization was discussed. In this case
      a mock GPIO is assumed to be the best compromise
      gaining some reuse of infrastructure without making
      DRM drivers overly complex at the same time. Let's
      see.
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Merge tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.1 development cycle:

   - A new GPIO hogging mechanism has been added.  This can be used on
     boards that want to drive some GPIO line high, low, or set it as
     input on boot and then never touch it again.  For some embedded
     systems this is bliss and simplifies things to a great extent.

   - Some API cleanup and closure: gpiod_get_array() and
     gpiod_put_array() has been added to get and put GPIOs in bulk as
     was possible with the non-descriptor API.

   - Encapsulate cross-calls to the pin control subsystem in
     <linux/gpio/driver.h>.  Now this should be the only header any GPIO
     driver needs to include or something is wrong.  Cleanups
     restricting drivers to this include are welcomed if tested.

   - Sort the GPIO Kconfig and split it into submenus, as it was
     becoming and unstructured, illogical and unnavigatable mess.  I
     hope this is easier to follow.  Menus that require a certain
     subsystem like I2C can now be hidden nicely for example, still
     working on others.

   - New drivers:

       - New driver for the Altera Soft GPIO.

       - The F7188x driver now handles the F71869 and F71869A variants.

       - The MIPS Loongson driver has been moved to drivers/gpio for
         consolidation and cleanup.

   - Cleanups:

       - The MAX732x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - The PCF857x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - Radical cleanup of the OMAP driver.

   - Misc:

       - Enable the DWAPB GPIO for all architectures.  This is a "hard
         IP" block from Synopsys which has started to turn up in so
         diverse architectures as X86 Quark, ARC and a slew of ARM
         systems.  So even though it's not an expander, it's generic
         enough to be available for all.

       - We add a mock GPIO on Crystalcove PMIC after a long discussion
         with Daniel Vetter et al, tracing back to the shootout at the
         kernel summit where DRM drivers and sub-componentization was
         discussed.  In this case a mock GPIO is assumed to be the best
         compromise gaining some reuse of infrastructure without making
         DRM drivers overly complex at the same time.  Let's see"

* tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits)
  Revert "gpio: sch: use uapi/linux/pci_ids.h directly"
  gpio: dwapb: remove dependencies
  gpio: dwapb: enable for ARC
  gpio: removing kfree remove functionality
  gpio: mvebu: Fix mask/unmask managment per irq chip type
  gpio: split GPIO drivers in submenus
  gpio: move MFD GPIO drivers under their own comment
  gpio: move BCM Kona Kconfig option
  gpio: arrange SPI Kconfig symbols alphabetically
  gpio: arrange PCI GPIO controllers alphabetically
  gpio: arrange I2C Kconfig symbols alphabetically
  gpio: arrange Kconfig symbols alphabetically
  gpio: ich: Implement get_direction function
  gpio: use (!foo) instead of (foo == NULL)
  gpio: arizona: drop owner assignment from platform_drivers
  gpio: max7300: remove 'ret' variable
  gpio: use devm_kzalloc
  gpio: sch: use uapi/linux/pci_ids.h directly
  gpio: x-gene: fix devm_ioremap_resource() check
  gpio: loongson: Add Loongson-3A/3B GPIO driver support
  ...
2015-04-18 08:22:10 -04:00
Linus Torvalds
54e514b91b Merge branch 'akpm' (patches from Andrew)
Merge third patchbomb from Andrew Morton:

 - various misc things

 - a couple of lib/ optimisations

 - provide DIV_ROUND_CLOSEST_ULL()

 - checkpatch updates

 - rtc tree

 - befs, nilfs2, hfs, hfsplus, fatfs, adfs, affs, bfs

 - ptrace fixes

 - fork() fixes

 - seccomp cleanups

 - more mmap_sem hold time reductions from Davidlohr

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (138 commits)
  proc: show locks in /proc/pid/fdinfo/X
  docs: add missing and new /proc/PID/status file entries, fix typos
  drivers/rtc/rtc-at91rm9200.c: make IO endian agnostic
  Documentation/spi/spidev_test.c: fix warning
  drivers/rtc/rtc-s5m.c: allow usage on device type different than main MFD type
  .gitignore: ignore *.tar
  MAINTAINERS: add Mediatek SoC mailing list
  tomoyo: reduce mmap_sem hold for mm->exe_file
  powerpc/oprofile: reduce mmap_sem hold for exe_file
  oprofile: reduce mmap_sem hold for mm->exe_file
  mips: ip32: add platform data hooks to use DS1685 driver
  lib/Kconfig: fix up HAVE_ARCH_BITREVERSE help text
  x86: switch to using asm-generic for seccomp.h
  sparc: switch to using asm-generic for seccomp.h
  powerpc: switch to using asm-generic for seccomp.h
  parisc: switch to using asm-generic for seccomp.h
  mips: switch to using asm-generic for seccomp.h
  microblaze: use asm-generic for seccomp.h
  arm: use asm-generic for seccomp.h
  seccomp: allow COMPAT sigreturn overrides
  ...
2015-04-17 09:04:38 -04:00
Kees Cook
ddaa27ee62 seccomp: allow COMPAT sigreturn overrides
Most architectures don't need to do much special for the strict-mode
seccomp syscall entries.  Remove the redundant headers and reduce the
others.

This patch (of 8):

Some architectures may need to override the compat sigreturn definition,
as is already possible in the non-compat case.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:09 -04:00
Linus Torvalds
eabbfdecda Merge branch 'for-v4.1-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping
Pull DMA-mapping updates from Marek Szyprowski:
 "This contains two patches, which clarify abiguity in the dma-mapping
  api"

* 'for-v4.1-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
  include/dma-mapping: Clarify output of dma_map_sg
  asm/dma-mapping-common: Clarify output of dma_map_sg_attrs
2015-04-16 18:50:27 -04:00
Linus Torvalds
bb0fd7ab09 Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
 "Included in this update are both some long term fixes and some new
  features.

  Fixes:

   - An integer overflow in the calculation of ELF_ET_DYN_BASE.

   - Avoiding OOMs for high-order IOMMU allocations

   - SMP requires the data cache to be enabled for synchronisation
     primitives to work, so prevent the CPU_DCACHE_DISABLE option being
     visible on SMP builds.

   - A bug going back 10+ years in the noMMU ARM94* CPU support code,
     where it corrupts registers.  Found by folk getting Linux running
     on their cameras.

   - Versatile Express needs an errata workaround enabled for CPU
     hot-unplug to work.

  Features:

   - Clean up module linker by handling out of range relocations
     separately from relocation cases we don't handle.

   - Fix a long term bug in the pci_mmap_page_range() code, which we
     hope won't impact userspace (we hope there's no users of the
     existing broken interface.)

   - Don't map DMA coherent allocations when we don't have a MMU.

   - Drop experimental status for SMP_ON_UP.

   - Warn when DT doesn't specify ePAPR mandatory cache properties.

   - Add documentation concerning how we find the start of physical
     memory for AUTO_ZRELADDR kernels, detailing why we have chosen the
     mask and the implications of changing it.

   - Updates from Ard Biesheuvel to address some issues with large
     kernels (such as allyesconfig) failing to link.

   - Allow hibernation to work on modern (ARMv7) CPUs - this appears to
     have never worked in the past on these CPUs.

   - Enable IRQ_SHOW_LEVEL, which changes the /proc/interrupts output
     format (hopefully without userspace breaking...  let's hope that if
     it causes someone a problem, they tell us.)

   - Fix tegra-ahb DT offsets.

   - Rework ARM errata 643719 code (and ARMv7 flush_cache_louis()/
     flush_dcache_all()) code to be more efficient, and enable this
     errata workaround by default for ARMv7+SMP CPUs.  This complements
     the Versatile Express fix above.

   - Rework ARMv7 context code for errata 430973, so that only Cortex A8
     CPUs are impacted by the branch target buffer flush when this
     errata is enabled.  Also update the help text to indicate that all
     r1p* A8 CPUs are impacted.

   - Switch ARM to the generic show_mem() implementation, it conveys all
     the information which we were already reporting.

   - Prevent slow timer sources being used for udelay() - timers running
     at less than 1MHz are not useful for this, and can cause udelay()
     to return immediately, without any wait.  Using such a slow timer
     is silly.

   - VDSO support for 32-bit ARM, mainly for gettimeofday() using the
     ARM architected timer.

   - Perf support for Scorpion performance monitoring units"

vdso semantic conflict fixed up as per linux-next.

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (52 commits)
  ARM: update errata 430973 documentation to cover Cortex A8 r1p*
  ARM: ensure delay timer has sufficient accuracy for delays
  ARM: switch to use the generic show_mem() implementation
  ARM: proc-v7: avoid errata 430973 workaround for non-Cortex A8 CPUs
  ARM: enable ARM errata 643719 workaround by default
  ARM: cache-v7: optimise test for Cortex A9 r0pX devices
  ARM: cache-v7: optimise branches in v7_flush_cache_louis
  ARM: cache-v7: consolidate initialisation of cache level index
  ARM: cache-v7: shift CLIDR to extract appropriate field before masking
  ARM: cache-v7: use movw/movt instructions
  ARM: allow 16-bit instructions in ALT_UP()
  ARM: proc-arm94*.S: fix setup function
  ARM: vexpress: fix CPU hotplug with CT9x4 tile.
  ARM: 8276/1: Make CPU_DCACHE_DISABLE depend on !SMP
  ARM: 8335/1: Documentation: DT bindings: Tegra AHB: document the legacy base address
  ARM: 8334/1: amba: tegra-ahb: detect and correct bogus base address
  ARM: 8333/1: amba: tegra-ahb: fix register offsets in the macros
  ARM: 8339/1: Enable CONFIG_GENERIC_IRQ_SHOW_LEVEL
  ARM: 8338/1: kexec: Relax SMP validation to improve DT compatibility
  ARM: 8337/1: mm: Do not invoke OOM for higher order IOMMU DMA allocations
  ...
2015-04-14 21:03:26 -07:00
Linus Torvalds
2481bc7528 Power management and ACPI updates for v4.1-rc1
- Generic PM domains support update including new PM domain
    callbacks to handle device initialization better (Russell King,
    Rafael J Wysocki, Kevin Hilman).
 
  - Unified device properties API update including a new mechanism
    for accessing data provided by platform initialization code
    (Rafael J Wysocki, Adrian Hunter).
 
  - ARM cpuidle update including ARM32/ARM64 handling consolidation
    (Daniel Lezcano).
 
  - intel_idle update including support for the Silvermont Core in
    the Baytrail SOC and for the Airmont Core in the Cherrytrail and
    Braswell SOCs (Len Brown, Mathias Krause).
 
  - New cpufreq driver for Hisilicon ACPU (Leo Yan).
 
  - intel_pstate update including support for the Knights Landing
    chip (Dasaratharaman Chandramouli, Kristen Carlson Accardi).
 
  - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann).
 
  - powernv cpufreq driver update (Shilpasri G Bhat).
 
  - devfreq update including Tegra support changes (Tomeu Vizoso,
    MyungJoo Ham, Chanwoo Choi).
 
  - powercap RAPL (Running-Average Power Limit) driver update
    including support for Intel Broadwell server chips (Jacob Pan,
    Mathias Krause).
 
  - ACPI device enumeration update related to the handling of the
    special PRP0001 device ID allowing DT-style 'compatible' property
    to be used for ACPI device identification (Rafael J Wysocki).
 
  - ACPI EC driver update including limited _DEP support (Lan Tianyu,
    Lv Zheng).
 
  - ACPI backlight driver update including a new mechanism to allow
    native backlight handling to be forced on non-Windows 8 systems
    and a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede).
 
  - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu).
 
  - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
    Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki).
 
  - Fixes related to suspend-to-idle for the iTCO watchdog driver and
    the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu).
 
  - PM tracing support for the suspend phase of system suspend/resume
    transitions (Zhonghui Fu).
 
  - Configurable delay for the system suspend/resume testing facility
    (Brian Norris).
 
  - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki).
 
 /
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Merge tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "These are mostly fixes and cleanups all over, although there are a few
  items that sort of fall into the new feature category.

  First off, we have new callbacks for PM domains that should help us to
  handle some issues related to device initialization in a better way.

  There also is some consolidation in the unified device properties API
  area allowing us to use that inferface for accessing data coming from
  platform initialization code in addition to firmware-provided data.

  We have some new device/CPU IDs in a few drivers, support for new
  chips and a new cpufreq driver too.

  Specifics:

   - Generic PM domains support update including new PM domain callbacks
     to handle device initialization better (Russell King, Rafael J
     Wysocki, Kevin Hilman)

   - Unified device properties API update including a new mechanism for
     accessing data provided by platform initialization code (Rafael J
     Wysocki, Adrian Hunter)

   - ARM cpuidle update including ARM32/ARM64 handling consolidation
     (Daniel Lezcano)

   - intel_idle update including support for the Silvermont Core in the
     Baytrail SOC and for the Airmont Core in the Cherrytrail and
     Braswell SOCs (Len Brown, Mathias Krause)

   - New cpufreq driver for Hisilicon ACPU (Leo Yan)

   - intel_pstate update including support for the Knights Landing chip
     (Dasaratharaman Chandramouli, Kristen Carlson Accardi)

   - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann)

   - powernv cpufreq driver update (Shilpasri G Bhat)

   - devfreq update including Tegra support changes (Tomeu Vizoso,
     MyungJoo Ham, Chanwoo Choi)

   - powercap RAPL (Running-Average Power Limit) driver update including
     support for Intel Broadwell server chips (Jacob Pan, Mathias Krause)

   - ACPI device enumeration update related to the handling of the
     special PRP0001 device ID allowing DT-style 'compatible' property
     to be used for ACPI device identification (Rafael J Wysocki)

   - ACPI EC driver update including limited _DEP support (Lan Tianyu,
     Lv Zheng)

   - ACPI backlight driver update including a new mechanism to allow
     native backlight handling to be forced on non-Windows 8 systems and
     a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede)

   - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu)

   - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
     Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki)

   - Fixes related to suspend-to-idle for the iTCO watchdog driver and
     the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu)

   - PM tracing support for the suspend phase of system suspend/resume
     transitions (Zhonghui Fu)

   - Configurable delay for the system suspend/resume testing facility
     (Brian Norris)

   - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki)"

* tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
  ACPI / scan: Fix NULL pointer dereference in acpi_companion_match()
  ACPI / scan: Rework modalias creation when "compatible" is present
  intel_idle: mark cpu id array as __initconst
  powercap / RAPL: mark rapl_ids array as __initconst
  powercap / RAPL: add ID for Broadwell server
  intel_pstate: Knights Landing support
  intel_pstate: remove MSR test
  cpufreq: fix qoriq uniprocessor build
  ACPI / scan: Take the PRP0001 position in the list of IDs into account
  ACPI / scan: Simplify acpi_match_device()
  ACPI / scan: Generalize of_compatible matching
  device property: Introduce firmware node type for platform data
  device property: Make it possible to use secondary firmware nodes
  PM / watchdog: iTCO: stop watchdog during system suspend
  cpufreq: hisilicon: add acpu driver
  ACPI / EC: Call acpi_walk_dep_device_list() after installing EC opregion handler
  cpufreq: powernv: Report cpu frequency throttling
  intel_idle: Add support for the Airmont Core in the Cherrytrail and Braswell SOCs
  intel_idle: Update support for Silvermont Core in Baytrail SOC
  PM / devfreq: tegra: Register governor on module init
  ...
2015-04-14 20:21:54 -07:00
Linus Torvalds
1dcf58d6e6 Merge branch 'akpm' (patches from Andrew)
Merge first patchbomb from Andrew Morton:

 - arch/sh updates

 - ocfs2 updates

 - kernel/watchdog feature

 - about half of mm/

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits)
  Documentation: update arch list in the 'memtest' entry
  Kconfig: memtest: update number of test patterns up to 17
  arm: add support for memtest
  arm64: add support for memtest
  memtest: use phys_addr_t for physical addresses
  mm: move memtest under mm
  mm, hugetlb: abort __get_user_pages if current has been oom killed
  mm, mempool: do not allow atomic resizing
  memcg: print cgroup information when system panics due to panic_on_oom
  mm: numa: remove migrate_ratelimited
  mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE
  mm: split ET_DYN ASLR from mmap ASLR
  s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE
  mm: expose arch_mmap_rnd when available
  s390: standardize mmap_rnd() usage
  powerpc: standardize mmap_rnd() usage
  mips: extract logic for mmap_rnd()
  arm64: standardize mmap_rnd() usage
  x86: standardize mmap_rnd() usage
  arm: factor out mmap ASLR into mmap_rnd
  ...
2015-04-14 16:49:17 -07:00
Toshi Kani
b9820d8f39 mm: change vunmap to tear down huge KVA mappings
Change vunmap_pmd_range() and vunmap_pud_range() to tear down huge KVA
mappings when they are set.  pud_clear_huge() and pmd_clear_huge() return
zero when no-operation is performed, i.e.  huge page mapping was not used.

These changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined
on the architecture.

[akpm@linux-foundation.org: use consistent code layout]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:04 -07:00
Toshi Kani
e61ce6ade4 mm: change ioremap to set up huge I/O mappings
ioremap_pud_range() and ioremap_pmd_range() are changed to create huge I/O
mappings when their capability is enabled, and a request meets required
conditions -- both virtual & physical addresses are aligned by their huge
page size, and a requested range fufills their huge page size.  When
pud_set_huge() or pmd_set_huge() returns zero, i.e.  no-operation is
performed, the code simply falls back to the next level.

The changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on
the architecture.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:04 -07:00
Kirill A. Shutemov
235a8f0286 mm: define default PGTABLE_LEVELS to two
By this time all architectures which support more than two page table
levels should be covered.  This patch add default definiton of
PGTABLE_LEVELS equal 2.

We also add assert to detect inconsistence between CONFIG_PGTABLE_LEVELS
and __PAGETABLE_PMD_FOLDED/__PAGETABLE_PUD_FOLDED.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:02 -07:00
Peter Hurley
99492c39f3 earlycon: Fix __earlycon_table stride
The compiler and the linker must agree on the alignment of
struct earlycon_id; empirical testing and commit 07fca0e57f
("tracing: Properly align linker defined symbols") suggests
32-byte alignment is the LCD.

Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-10 14:39:53 +02:00
Steven Rostedt (Red Hat)
0c564a538a tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values
Several tracepoints use the helper functions __print_symbolic() or
__print_flags() and pass in enums that do the mapping between the
binary data stored and the value to print. This works well for reading
the ASCII trace files, but when the data is read via userspace tools
such as perf and trace-cmd, the conversion of the binary value to a
human string format is lost if an enum is used, as userspace does not
have access to what the ENUM is.

For example, the tracepoint trace_tlb_flush() has:

 __print_symbolic(REC->reason,
    { TLB_FLUSH_ON_TASK_SWITCH, "flush on task switch" },
    { TLB_REMOTE_SHOOTDOWN, "remote shootdown" },
    { TLB_LOCAL_SHOOTDOWN, "local shootdown" },
    { TLB_LOCAL_MM_SHOOTDOWN, "local mm shootdown" })

Which maps the enum values to the strings they represent. But perf and
trace-cmd do no know what value TLB_LOCAL_MM_SHOOTDOWN is, and would
not be able to map it.

With TRACE_DEFINE_ENUM(), developers can place these in the event header
files and ftrace will convert the enums to their values:

By adding:

 TRACE_DEFINE_ENUM(TLB_FLUSH_ON_TASK_SWITCH);
 TRACE_DEFINE_ENUM(TLB_REMOTE_SHOOTDOWN);
 TRACE_DEFINE_ENUM(TLB_LOCAL_SHOOTDOWN);
 TRACE_DEFINE_ENUM(TLB_LOCAL_MM_SHOOTDOWN);

 $ cat /sys/kernel/debug/tracing/events/tlb/tlb_flush/format
[...]
 __print_symbolic(REC->reason,
    { 0, "flush on task switch" },
    { 1, "remote shootdown" },
    { 2, "local shootdown" },
    { 3, "local mm shootdown" })

The above is what userspace expects to see, and tools do not need to
be modified to parse them.

Link: http://lkml.kernel.org/r/20150403013802.220157513@goodmis.org

Cc: Guilherme Cox <cox@computer.org>
Cc: Tony Luck <tony.luck@gmail.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-08 09:39:56 -04:00
Ard Biesheuvel
779c88c94c ARM: 8321/1: asm-generic: introduce .text.fixup input section
This introduces a new .text.fixup input section that gets emitted
together with the .text section for each input object file.

Note that

  *(.text)
  *(.text.fixup)

is not the same as

  *(.text .text.fixup)

and we are looking for the latter, to ensure that fixup snippets that
are assembled into a separate section in the object file do not end
up out of range for the relative branch instructions it contains if
the .text section itself grows very large.

This helps prevent linker failures on large ARM kernels.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-29 23:11:55 +01:00
Peter Hurley
470ca0de69 serial: earlycon: Enable earlycon without command line param
Earlycon matching can only be triggered if 'earlycon=...' has been
specified on the kernel command line. To workaround this limitation
requires tight coupling between arches and specific serial drivers
in order to start an earlycon. Devicetree avoids this limitation
with a link table that contains the required data to match earlycons.

Mirror this approach for earlycon match by name. Re-purpose
EARLYCON_DECLARE to generate a table entry which associates name with
setup() function. Re-purpose setup_earlycon() to scan this table for
an earlycon match, which is registered if found.

Declare one "earlycon" early_param, which calls setup_earlycon().

This design allows setup_earlycon() to be called directly with a
param string (as if 'earlycon=...' had been set on the command line).
Re-registration (either directly or by early_param) is prevented.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 17:25:27 +01:00
Daniel Lezcano
449e056c76 ARM: cpuidle: Add a cpuidle ops structure to be used for DT
The current state of the different cpuidle drivers is the different PM
operations are passed via the platform_data using the platform driver
paradigm.

This approach allowed to split the low level PM code from the arch specific
and the generic cpuidle code.

Unfortunately there are complaints about this approach as, in the context of the
single kernel image, we have multiple drivers loaded in memory for nothing and
the platform driver is not adequate for cpuidle.

This patch provides a common interface via cpuidle ops for all new cpuidle
driver and a definition for the device tree.

It will allow with the next patches to a have a common definition with ARM64
and share the same cpuidle driver.

The code is optimized to use the __init section intensively in order to reduce
the memory footprint after the driver is initialized and unify the function
names with ARM64.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Rob Herring <robherring2@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2015-03-24 10:16:01 +01:00
Linus Walleij
964cb34188 gpio: move pincontrol calls to <linux/gpio/driver.h>
These functions do not belong in <asm-generic/gpio.h> since the
split into separate GPIO headers under <linux/gpio/*>. Move them
to <linux/gpio/driver.h> as is apropriate.

Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-19 09:45:54 +01:00
Ricardo Ribalda Delgado
8582e267e9 asm/dma-mapping-common: Clarify output of dma_map_sg_attrs
Although dma_map_sg_attrs returns 0 on error and it cannot return a
value < 0, the function returns a signed integer.

Most of the time, this function is used with a scatterlist structure.
This structure uses an unsigned integer for the number of memory.

A dma developer that has not read in detail DMA-API.txt, can wrongly
return a value < 0 on error.

The comment will help the driver developer, and the WARN_ON the dma
developer.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2015-03-09 13:05:47 +01:00
Linus Torvalds
53861af9a1 OK, this has the big virtio 1.0 implementation, as specified by OASIS.
On top of tht is the major rework of lguest, to use PCI and virtio 1.0, to
 double-check the implementation.
 
 Then comes the inevitable fixes and cleanups from that work.
 
 Thanks,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "OK, this has the big virtio 1.0 implementation, as specified by OASIS.

  On top of tht is the major rework of lguest, to use PCI and virtio
  1.0, to double-check the implementation.

  Then comes the inevitable fixes and cleanups from that work"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (80 commits)
  virtio: don't set VIRTIO_CONFIG_S_DRIVER_OK twice.
  virtio_net: unconditionally define struct virtio_net_hdr_v1.
  tools/lguest: don't use legacy definitions for net device in example launcher.
  virtio: Don't expose legacy net features when VIRTIO_NET_NO_LEGACY defined.
  tools/lguest: use common error macros in the example launcher.
  tools/lguest: give virtqueues names for better error messages
  tools/lguest: more documentation and checking of virtio 1.0 compliance.
  lguest: don't look in console features to find emerg_wr.
  tools/lguest: don't start devices until DRIVER_OK status set.
  tools/lguest: handle indirect partway through chain.
  tools/lguest: insert driver references from the 1.0 spec (4.1 Virtio Over PCI)
  tools/lguest: insert device references from the 1.0 spec (4.1 Virtio Over PCI)
  tools/lguest: rename virtio_pci_cfg_cap field to match spec.
  tools/lguest: fix features_accepted logic in example launcher.
  tools/lguest: handle device reset correctly in example launcher.
  virtual: Documentation: simplify and generalize paravirt_ops.txt
  lguest: remove NOTIFY call and eventfd facility.
  lguest: remove NOTIFY facility from demonstration launcher.
  lguest: use the PCI console device's emerg_wr for early boot messages.
  lguest: always put console in PCI slot #1.
  ...
2015-02-18 09:24:01 -08:00
Andrey Ryabinin
9ddf82521c kernel: add support for .init_array.* constructors
KASan uses constructors for initializing redzones for global variables.
Globals instrumentation in GCC 4.9.2 produces constructors with priority
(.init_array.00099)

Currently kernel ignores such constructors.  Only constructors with
default priority supported (.init_array)

This patch adds support for constructors with priorities.  For kernel
image we put pointers to constructors between __ctors_start/__ctors_end
and do_ctors() will call them on start up.  For modules we merge
.init_array.* sections into resulting .init_array.  Module code properly
handles constructors in .init_array section.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:42 -08:00
Mel Gorman
21d9ee3eda mm: remove remaining references to NUMA hinting bits and helpers
This patch removes the NUMA PTE bits and associated helpers.  As a
side-effect it increases the maximum possible swap space on x86-64.

One potential source of problems is races between the marking of PTEs
PROT_NONE, NUMA hinting faults and migration.  It must be guaranteed that
a PTE being protected is not faulted in parallel, seen as a pte_none and
corrupting memory.  The base case is safe but transhuge has problems in
the past due to an different migration mechanism and a dependance on page
lock to serialise migrations and warrants a closer look.

task_work hinting update			parallel fault
------------------------			--------------
change_pmd_range
  change_huge_pmd
    __pmd_trans_huge_lock
      pmdp_get_and_clear
						__handle_mm_fault
						pmd_none
						  do_huge_pmd_anonymous_page
						  read? pmd_lock blocks until hinting complete, fail !pmd_none test
						  write? __do_huge_pmd_anonymous_page acquires pmd_lock, checks pmd_none
      pmd_modify
      set_pmd_at

task_work hinting update			parallel migration
------------------------			------------------
change_pmd_range
  change_huge_pmd
    __pmd_trans_huge_lock
      pmdp_get_and_clear
						__handle_mm_fault
						  do_huge_pmd_numa_page
						    migrate_misplaced_transhuge_page
						    pmd_lock waits for updates to complete, recheck pmd_same
      pmd_modify
      set_pmd_at

Both of those are safe and the case where a transhuge page is inserted
during a protection update is unchanged.  The case where two processes try
migrating at the same time is unchanged by this series so should still be
ok.  I could not find a case where we are accidentally depending on the
PTE not being cleared and flushed.  If one is missed, it'll manifest as
corruption problems that start triggering shortly after this series is
merged and only happen when NUMA balancing is enabled.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:08 -08:00
Mel Gorman
e7bb4b6d16 mm: add p[te|md] protnone helpers for use by NUMA balancing
This is a preparatory patch that introduces protnone helpers for automatic
NUMA balancing.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:08 -08:00
Kirill A. Shutemov
4155b8e0a7 mm, asm-generic: define PUD_SHIFT in <asm-generic/4level-fixup.h>
If an architecure uses <asm-generic/4level-fixup.h>, build fails if we
try to use PUD_SHIFT in generic code:

   In file included from arch/microblaze/include/asm/bug.h:1:0,
                    from include/linux/bug.h:4,
                    from include/linux/thread_info.h:11,
                    from include/asm-generic/preempt.h:4,
                    from arch/microblaze/include/generated/asm/preempt.h:1,
                    from include/linux/preempt.h:18,
                    from include/linux/spinlock.h:50,
                    from include/linux/mmzone.h:7,
                    from include/linux/gfp.h:5,
                    from include/linux/slab.h:14,
                    from mm/mmap.c:12:
   mm/mmap.c: In function 'exit_mmap':
>> mm/mmap.c:2858:46: error: 'PUD_SHIFT' undeclared (first use in this function)
       round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT);
                                                 ^
   include/asm-generic/bug.h:86:25: note: in definition of macro 'WARN_ON'
     int __ret_warn_on = !!(condition);    \
                            ^
   mm/mmap.c:2858:46: note: each undeclared identifier is reported only once for each function it appears in
       round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT);
                                                 ^
   include/asm-generic/bug.h:86:25: note: in definition of macro 'WARN_ON'
     int __ret_warn_on = !!(condition);    \
                            ^
As with <asm-generic/pgtable-nopud.h>, let's define PUD_SHIFT to
PGDIR_SHIFT.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:03 -08:00
Kirill A. Shutemov
5064c8e19d asm-generic: drop unused pte_file* helpers
All users are gone.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:31 -08:00
Michael S. Tsirkin
eb29d8d2aa pci: add pci_iomap_range
Virtio drivers should map the part of the BAR they need, not necessarily
all of it.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:49 +10:30
Will Deacon
721c21c17a mm: mmu_gather: use tlb->end != 0 only for TLB invalidation
When batching up address ranges for TLB invalidation, we check tlb->end
!= 0 to indicate that some pages have actually been unmapped.

As of commit f045bbb9fa ("mmu_gather: fix over-eager
tlb_flush_mmu_free() calling"), we use the same check for freeing these
pages in order to avoid a performance regression where we call
free_pages_and_swap_cache even when no pages are actually queued up.

Unfortunately, the range could have been reset (tlb->end = 0) by
tlb_end_vma, which has been shown to cause memory leaks on arm64.
Furthermore, investigation into these leaks revealed that the fullmm
case on task exit no longer invalidates the TLB, by virtue of tlb->end
 == 0 (in 3.18, need_flush would have been set).

This patch resolves the problem by reverting commit f045bbb9fa, using
instead tlb->local.nr as the predicate for page freeing in
tlb_flush_mmu_free and ensuring that tlb->end is initialised to a
non-zero value in the fullmm case.

Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Dave Hansen <dave@sr71.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-13 15:20:40 +13:00
Linus Torvalds
6f51ee709e ARM: SoC/iommu configuration for 3.19
The iomm-config branch contains work from Will Deacon, quoting his description:
 
     This series adds automatic IOMMU and DMA-mapping configuration for
     OF-based DMA masters described using the generic IOMMU devicetree
     bindings. Although there is plenty of future work around splitting up
     iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
     group creation for the platform_bus, this is already useful enough for
     people to port over their IOMMU drivers and start using the new probing
     infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).
 
 The branch touches core ARM and IOMMU driver files, and the respective
 maintainers (Russell King and Joerg Roedel) agreed to have the contents
 merged through the arm-soc tree. The final version was ready just before
 the merge window, so we ended up delaying it a bit longer than the rest,
 but we don't expect to see regressions because this is just additional
 infrastructure that will get used in drivers starting in 3.20 but is
 unused so far.
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Merge tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC/iommu configuration update from Arnd Bergmann:
 "The iomm-config branch contains work from Will Deacon, quoting his
  description:

    This series adds automatic IOMMU and DMA-mapping configuration for
    OF-based DMA masters described using the generic IOMMU devicetree
    bindings. Although there is plenty of future work around splitting up
    iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
    group creation for the platform_bus, this is already useful enough for
    people to port over their IOMMU drivers and start using the new probing
    infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).

  The branch touches core ARM and IOMMU driver files, and the respective
  maintainers (Russell King and Joerg Roedel) agreed to have the
  contents merged through the arm-soc tree.

  The final version was ready just before the merge window, so we ended
  up delaying it a bit longer than the rest, but we don't expect to see
  regressions because this is just additional infrastructure that will
  get used in drivers starting in 3.20 but is unused so far"

* tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  iommu: store DT-probed IOMMU data privately
  arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops
  arm: call iommu_init before of_platform_populate
  dma-mapping: detect and configure IOMMU in of_dma_configure
  iommu: fix initialization without 'add_device' callback
  iommu: provide helper function to configure an IOMMU for an of master
  iommu: add new iommu_ops callback for adding an OF device
  dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops
  iommu: provide early initialisation hook for IOMMU drivers
2014-12-16 14:53:01 -08:00
Linus Torvalds
f96fe22567 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull another networking update from David Miller:
 "Small follow-up to the main merge pull from the other day:

  1) Alexander Duyck's DMA memory barrier patch set.

  2) cxgb4 driver fixes from Karen Xie.

  3) Add missing export of fixed_phy_register() to modules, from Mark
     Salter.

  4) DSA bug fixes from Florian Fainelli"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (24 commits)
  net/macb: add TX multiqueue support for gem
  linux/interrupt.h: remove the definition of unused tasklet_hi_enable
  jme: replace calls to redundant function
  net: ethernet: davicom: Allow to select DM9000 for nios2
  net: ethernet: smsc: Allow to select SMC91X for nios2
  cxgb4: Add support for QSA modules
  libcxgbi: fix freeing skb prematurely
  cxgb4i: use set_wr_txq() to set tx queues
  cxgb4i: handle non-pdu-aligned rx data
  cxgb4i: additional types of negative advice
  cxgb4/cxgb4i: set the max. pdu length in firmware
  cxgb4i: fix credit check for tx_data_wr
  cxgb4i: fix tx immediate data credit check
  net: phy: export fixed_phy_register()
  fib_trie: Fix trie balancing issue if new node pushes down existing node
  vlan: Add ability to always enable TSO/UFO
  r8169:update rtl8168g pcie ephy parameter
  net: dsa: bcm_sf2: force link for all fixed PHY devices
  fm10k/igb/ixgbe: Use dma_rmb on Rx descriptor reads
  r8169: Use dma_rmb() and dma_wmb() for DescOwn checks
  ...
2014-12-12 16:11:12 -08:00
Alexander Duyck
1077fa36f2 arch: Add lightweight memory barriers dma_rmb() and dma_wmb()
There are a number of situations where the mandatory barriers rmb() and
wmb() are used to order memory/memory operations in the device drivers
and those barriers are much heavier than they actually need to be.  For
example in the case of PowerPC wmb() calls the heavy-weight sync
instruction when for coherent memory operations all that is really needed
is an lsync or eieio instruction.

This commit adds a coherent only version of the mandatory memory barriers
rmb() and wmb().  In most cases this should result in the barrier being the
same as the SMP barriers for the SMP case, however in some cases we use a
barrier that is somewhere in between rmb() and smp_rmb().  For example on
ARM the rmb barriers break down as follows:

  Barrier   Call     Explanation
  --------- -------- ----------------------------------
  rmb()     dsb()    Data synchronization barrier - system
  dma_rmb() dmb(osh) data memory barrier - outer sharable
  smp_rmb() dmb(ish) data memory barrier - inner sharable

These new barriers are not as safe as the standard rmb() and wmb().
Specifically they do not guarantee ordering between coherent and incoherent
memories.  The primary use case for these would be to enforce ordering of
reads and writes when accessing coherent memory that is shared between the
CPU and a device.

It may also be noted that there is no dma_mb().  Most architectures don't
provide a good mechanism for performing a coherent only full barrier without
resorting to the same mechanism used in mb().  As such there isn't much to
be gained in trying to define such a function.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-11 21:15:06 -05:00
Linus Torvalds
27afc5dbda Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The most notable change for this pull request is the ftrace rework
  from Heiko.  It brings a small performance improvement and the ground
  work to support a new gcc option to replace the mcount blocks with a
  single nop.

  Two new s390 specific system calls are added to emulate user space
  mmio for PCI, an artifact of the how PCI memory is accessed.

  Two patches for the memory management with changes to common code.
  For KVM mm_forbids_zeropage is added which disables the empty zero
  page for an mm that is used by a KVM process.  And an optimization,
  pmdp_get_and_clear_full is added analog to ptep_get_and_clear_full.

  Some micro optimization for the cmpxchg and the spinlock code.

  And as usual bug fixes and cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (46 commits)
  s390/cputime: fix 31-bit compile
  s390/scm_block: make the number of reqs per HW req configurable
  s390/scm_block: handle multiple requests in one HW request
  s390/scm_block: allocate aidaw pages only when necessary
  s390/scm_block: use mempool to manage aidaw requests
  s390/eadm: change timeout value
  s390/mm: fix memory leak of ptlock in pmd_free_tlb
  s390: use local symbol names in entry[64].S
  s390/ptrace: always include vector registers in core files
  s390/simd: clear vector register pointer on fork/clone
  s390: translate cputime magic constants to macros
  s390/idle: convert open coded idle time seqcount
  s390/idle: add missing irq off lockdep annotation
  s390/debug: avoid function call for debug_sprintf_*
  s390/kprobes: fix instruction copy for out of line execution
  s390: remove diag 44 calls from cpu_relax()
  s390/dasd: retry partition detection
  s390/dasd: fix list corruption for sleep_on requests
  s390/dasd: fix infinite term I/O loop
  s390/dasd: remove unused code
  ...
2014-12-11 17:30:55 -08:00
Linus Torvalds
70e71ca0af Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New offloading infrastructure and example 'rocker' driver for
    offloading of switching and routing to hardware.

    This work was done by a large group of dedicated individuals, not
    limited to: Scott Feldman, Jiri Pirko, Thomas Graf, John Fastabend,
    Jamal Hadi Salim, Andy Gospodarek, Florian Fainelli, Roopa Prabhu

 2) Start making the networking operate on IOV iterators instead of
    modifying iov objects in-situ during transfers.  Thanks to Al Viro
    and Herbert Xu.

 3) A set of new netlink interfaces for the TIPC stack, from Richard
    Alpe.

 4) Remove unnecessary looping during ipv6 routing lookups, from Martin
    KaFai Lau.

 5) Add PAUSE frame generation support to gianfar driver, from Matei
    Pavaluca.

 6) Allow for larger reordering levels in TCP, which are easily
    achievable in the real world right now, from Eric Dumazet.

 7) Add a variable of napi_schedule that doesn't need to disable cpu
    interrupts, from Eric Dumazet.

 8) Use a doubly linked list to optimize neigh_parms_release(), from
    Nicolas Dichtel.

 9) Various enhancements to the kernel BPF verifier, and allow eBPF
    programs to actually be attached to sockets.  From Alexei
    Starovoitov.

10) Support TSO/LSO in sunvnet driver, from David L Stevens.

11) Allow controlling ECN usage via routing metrics, from Florian
    Westphal.

12) Remote checksum offload, from Tom Herbert.

13) Add split-header receive, BQL, and xmit_more support to amd-xgbe
    driver, from Thomas Lendacky.

14) Add MPLS support to openvswitch, from Simon Horman.

15) Support wildcard tunnel endpoints in ipv6 tunnels, from Steffen
    Klassert.

16) Do gro flushes on a per-device basis using a timer, from Eric
    Dumazet.  This tries to resolve the conflicting goals between the
    desired handling of bulk vs.  RPC-like traffic.

17) Allow userspace to ask for the CPU upon what a packet was
    received/steered, via SO_INCOMING_CPU.  From Eric Dumazet.

18) Limit GSO packets to half the current congestion window, from Eric
    Dumazet.

19) Add a generic helper so that all drivers set their RSS keys in a
    consistent way, from Eric Dumazet.

20) Add xmit_more support to enic driver, from Govindarajulu
    Varadarajan.

21) Add VLAN packet scheduler action, from Jiri Pirko.

22) Support configurable RSS hash functions via ethtool, from Eyal
    Perry.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1820 commits)
  Fix race condition between vxlan_sock_add and vxlan_sock_release
  net/macb: fix compilation warning for print_hex_dump() called with skb->mac_header
  net/mlx4: Add support for A0 steering
  net/mlx4: Refactor QUERY_PORT
  net/mlx4_core: Add explicit error message when rule doesn't meet configuration
  net/mlx4: Add A0 hybrid steering
  net/mlx4: Add mlx4_bitmap zone allocator
  net/mlx4: Add a check if there are too many reserved QPs
  net/mlx4: Change QP allocation scheme
  net/mlx4_core: Use tasklet for user-space CQ completion events
  net/mlx4_core: Mask out host side virtualization features for guests
  net/mlx4_en: Set csum level for encapsulated packets
  be2net: Export tunnel offloads only when a VxLAN tunnel is created
  gianfar: Fix dma check map error when DMA_API_DEBUG is enabled
  cxgb4/csiostor: Don't use MASTER_MUST for fw_hello call
  net: fec: only enable mdio interrupt before phy device link up
  net: fec: clear all interrupt events to support i.MX6SX
  net: fec: reset fep link status in suspend function
  net: sock: fix access via invalid file descriptor
  net: introduce helper macro for_each_cmsghdr
  ...
2014-12-11 14:27:06 -08:00
Daniel Borkmann
0cb6c969ed net, lib: kill arch_fast_hash library bits
As there are now no remaining users of arch_fast_hash(), lets kill
it entirely.

This basically reverts commit 71ae8aac3e ("lib: introduce arch
optimized hash library") and follow-up work, that is f.e., commit
237217546d ("lib: hash: follow-up fixups for arch hash"),
commit e3fec2f74f ("lib: Add missing arch generic-y entries for
asm-generic/hash.h") and last but not least commit 6a02652df5
("perf tools: Fix include for non x86 architectures").

Cc: Francesco Fusco <fusco@ntop.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-10 15:17:46 -05:00
Linus Torvalds
3eb5b893eb Merge branch 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MPX support from Thomas Gleixner:
 "This enables support for x86 MPX.

  MPX is a new debug feature for bound checking in user space.  It
  requires kernel support to handle the bound tables and decode the
  bound violating instruction in the trap handler"

* 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  asm-generic: Remove asm-generic arch_bprm_mm_init()
  mm: Make arch_unmap()/bprm_mm_init() available to all architectures
  x86: Cleanly separate use of asm-generic/mm_hooks.h
  x86 mpx: Change return type of get_reg_offset()
  fs: Do not include mpx.h in exec.c
  x86, mpx: Add documentation on Intel MPX
  x86, mpx: Cleanup unused bound tables
  x86, mpx: On-demand kernel allocation of bounds tables
  x86, mpx: Decode MPX instruction to get bound violation information
  x86, mpx: Add MPX-specific mmap interface
  x86, mpx: Introduce VM_MPX to indicate that a VMA is MPX specific
  x86, mpx: Add MPX to disabled features
  ia64: Sync struct siginfo with general version
  mips: Sync struct siginfo with general version
  mpx: Extend siginfo structure to include bound violation information
  x86, mpx: Rename cfg_reg_u and status_reg
  x86: mpx: Give bndX registers actual names
  x86: Remove arbitrary instruction size limit in instruction decoder
2014-12-10 09:34:43 -08:00
Linus Torvalds
9e66645d72 Merge branch 'irq-irqdomain-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq domain updates from Thomas Gleixner:
 "The real interesting irq updates:

   - Support for hierarchical irq domains:

     For complex interrupt routing scenarios where more than one
     interrupt related chip is involved we had no proper representation
     in the generic interrupt infrastructure so far.  That made people
     implement rather ugly constructs in their nested irq chip
     implementations.  The main offenders are x86 and arm/gic.

     To distangle that mess we have now hierarchical irqdomains which
     seperate the various interrupt chips and connect them via the
     hierarchical domains.  That keeps the domain specific details
     internal to the particular hierarchy level and removes the
     criss/cross referencing of chip internals.  The resulting hierarchy
     for a complex x86 system will look like this:

        vector          mapped: 74
          msi-0         mapped: 2
          dmar-ir-1     mapped: 69
            ioapic-1    mapped: 4
            ioapic-0    mapped: 20
            pci-msi-2   mapped: 45
          dmar-ir-0     mapped: 3
            ioapic-2    mapped: 1
            pci-msi-1   mapped: 2
          htirq         mapped: 0

     Neither ioapic nor pci-msi know about the dmar interrupt remapping
     between themself and the vector domain.  If interrupt remapping is
     disabled ioapic and pci-msi become direct childs of the vector
     domain.

     In hindsight we should have done that years ago, but in hindsight
     we always know better :)

   - Support for generic MSI interrupt domain handling

     We have more and more non PCI related MSI interrupts, so providing
     a generic infrastructure for this is better than having all
     affected architectures implementing their own private hacks.

   - Support for PCI-MSI interrupt domain handling, based on the generic
     MSI support.

     This part carries the pci/msi branch from Bjorn Helgaas pci tree to
     avoid a massive conflict.  The PCI/MSI parts are acked by Bjorn.

  I have two more branches on top of this.  The full conversion of x86
  to hierarchical domains and a partial conversion of arm/gic"

* 'irq-irqdomain-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  genirq: Move irq_chip_write_msi_msg() helper to core
  PCI/MSI: Allow an msi_controller to be associated to an irq domain
  PCI/MSI: Provide mechanism to alloc/free MSI/MSIX interrupt from irqdomain
  PCI/MSI: Enhance core to support hierarchy irqdomain
  PCI/MSI: Move cached entry functions to irq core
  genirq: Provide default callbacks for msi_domain_ops
  genirq: Introduce msi_domain_alloc/free_irqs()
  asm-generic: Add msi.h
  genirq: Add generic msi irq domain support
  genirq: Introduce callback irq_chip.irq_write_msi_msg
  genirq: Work around __irq_set_handler vs stacked domains ordering issues
  irqdomain: Introduce helper function irq_domain_add_hierarchy()
  irqdomain: Implement a method to automatically call parent domains alloc/free
  genirq: Introduce helper irq_domain_set_info() to reduce duplicated code
  genirq: Split out flow handler typedefs into seperate header file
  genirq: Add IRQ_SET_MASK_OK_DONE to support stacked irqchip
  genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip
  genirq: Add more helper functions to support stacked irq_chip
  genirq: Introduce helper functions to support stacked irq_chip
  irqdomain: Do irq_find_mapping and set_type for hierarchy irqdomain in case OF
  ...
2014-12-10 09:01:01 -08:00
Linus Torvalds
86c6a2fddf Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - 'Nested Sleep Debugging', activated when CONFIG_DEBUG_ATOMIC_SLEEP=y.

     This instruments might_sleep() checks to catch places that nest
     blocking primitives - such as mutex usage in a wait loop.  Such
     bugs can result in hard to debug races/hangs.

     Another category of invalid nesting that this facility will detect
     is the calling of blocking functions from within schedule() ->
     sched_submit_work() -> blk_schedule_flush_plug().

     There's some potential for false positives (if secondary blocking
     primitives themselves are not ready yet for this facility), but the
     kernel will warn once about such bugs per bootup, so the warning
     isn't much of a nuisance.

     This feature comes with a number of fixes, for problems uncovered
     with it, so no messages are expected normally.

   - Another round of sched/numa optimizations and refinements, for
     CONFIG_NUMA_BALANCING=y.

   - Another round of sched/dl fixes and refinements.

  Plus various smaller fixes and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  sched: Add missing rcu protection to wake_up_all_idle_cpus
  sched/deadline: Introduce start_hrtick_dl() for !CONFIG_SCHED_HRTICK
  sched/numa: Init numa balancing fields of init_task
  sched/deadline: Remove unnecessary definitions in cpudeadline.h
  sched/cpupri: Remove unnecessary definitions in cpupri.h
  sched/deadline: Fix rq->dl.pushable_tasks bug in push_dl_task()
  sched/fair: Fix stale overloaded status in the busiest group finding logic
  sched: Move p->nr_cpus_allowed check to select_task_rq()
  sched/completion: Document when to use wait_for_completion_io_*()
  sched: Update comments about CLONE_NEWUTS and CLONE_NEWIPC
  sched/fair: Kill task_struct::numa_entry and numa_group::task_list
  sched: Refactor task_struct to use numa_faults instead of numa_* pointers
  sched/deadline: Don't check CONFIG_SMP in switched_from_dl()
  sched/deadline: Reschedule from switched_from_dl() after a successful pull
  sched/deadline: Push task away if the deadline is equal to curr during wakeup
  sched/deadline: Add deadline rq status print
  sched/deadline: Fix artificial overrun introduced by yield_task_dl()
  sched/rt: Clean up check_preempt_equal_prio()
  sched/core: Use dl_bw_of() under rcu_read_lock_sched()
  sched: Check if we got a shallowest_idle_cpu before searching for least_loaded_cpu
  ...
2014-12-09 21:21:34 -08:00
Linus Torvalds
a0e4467726 asm-generic: asm/io.h rewrite
While there normally is no reason to have a pull request for asm-generic
 but have all changes get merged through whichever tree needs them, I do
 have a series for 3.19. There are two sets of patches that change
 significant portions of asm/io.h, and this branch contains both in order
 to resolve the conflicts:
 
 - Will Deacon has done a set of patches to ensure that all architectures
   define {read,write}{b,w,l,q}_relaxed() functions or get them by
   including asm-generic/io.h. These functions are commonly used on ARM
   specific drivers to avoid expensive L2 cache synchronization implied by
   the normal {read,write}{b,w,l,q}, but we need to define them on all
   architectures in order to share the drivers across architectures and
   to enable CONFIG_COMPILE_TEST configurations for them
 
 - Thierry Reding has done an unrelated set of patches that extends
   the asm-generic/io.h file to the degree necessary to make it useful
   on ARM64 and potentially other architectures.
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Merge tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic asm/io.h rewrite from Arnd Bergmann:
 "While there normally is no reason to have a pull request for
  asm-generic but have all changes get merged through whichever tree
  needs them, I do have a series for 3.19.

  There are two sets of patches that change significant portions of
  asm/io.h, and this branch contains both in order to resolve the
  conflicts:

   - Will Deacon has done a set of patches to ensure that all
     architectures define {read,write}{b,w,l,q}_relaxed() functions or
     get them by including asm-generic/io.h.

     These functions are commonly used on ARM specific drivers to avoid
     expensive L2 cache synchronization implied by the normal
     {read,write}{b,w,l,q}, but we need to define them on all
     architectures in order to share the drivers across architectures
     and to enable CONFIG_COMPILE_TEST configurations for them

   - Thierry Reding has done an unrelated set of patches that extends
     the asm-generic/io.h file to the degree necessary to make it useful
     on ARM64 and potentially other architectures"

* tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (29 commits)
  ARM64: use GENERIC_PCI_IOMAP
  sparc: io: remove duplicate relaxed accessors on sparc32
  ARM: sa11x0: Use void __iomem * in MMIO accessors
  arm64: Use include/asm-generic/io.h
  ARM: Use include/asm-generic/io.h
  asm-generic/io.h: Implement generic {read,write}s*()
  asm-generic/io.h: Reconcile I/O accessor overrides
  /dev/mem: Use more consistent data types
  Change xlate_dev_{kmem,mem}_ptr() prototypes
  ARM: ixp4xx: Properly override I/O accessors
  ARM: ixp4xx: Fix build with IXP4XX_INDIRECT_PCI
  ARM: ebsa110: Properly override I/O accessors
  ARC: Remove redundant PCI_IOBASE declaration
  documentation: memory-barriers: clarify relaxed io accessor semantics
  x86: io: implement dummy relaxed accessor macros for writes
  tile: io: implement dummy relaxed accessor macros for writes
  sparc: io: implement dummy relaxed accessor macros for writes
  powerpc: io: implement dummy relaxed accessor macros for writes
  parisc: io: implement dummy relaxed accessor macros for writes
  mn10300: io: implement dummy relaxed accessor macros for writes
  ...
2014-12-09 17:25:00 -08:00
Linus Torvalds
b64bb1d758 arm64 updates for 3.19
Changes include:
  - Support for alternative instruction patching from Andre
  - seccomp from Akashi
  - Some AArch32 instruction emulation, required by the Android folks
  - Optimisations for exception entry/exit code, cmpxchg, pcpu atomics
  - mmu_gather range calculations moved into core code
  - EFI updates from Ard, including long-awaited SMBIOS support
  - /proc/cpuinfo fixes to align with the format used by arch/arm/
  - A few non-critical fixes across the architecture
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "Here's the usual mixed bag of arm64 updates, also including some
  related EFI changes (Acked by Matt) and the MMU gather range cleanup
  (Acked by you).

  Changes include:
   - support for alternative instruction patching from Andre
   - seccomp from Akashi
   - some AArch32 instruction emulation, required by the Android folks
   - optimisations for exception entry/exit code, cmpxchg, pcpu atomics
   - mmu_gather range calculations moved into core code
   - EFI updates from Ard, including long-awaited SMBIOS support
   - /proc/cpuinfo fixes to align with the format used by arch/arm/
   - a few non-critical fixes across the architecture"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits)
  arm64: remove the unnecessary arm64_swiotlb_init()
  arm64: add module support for alternatives fixups
  arm64: perf: Prevent wraparound during overflow
  arm64/include/asm: Fixed a warning about 'struct pt_regs'
  arm64: Provide a namespace to NCAPS
  arm64: bpf: lift restriction on last instruction
  arm64: Implement support for read-mostly sections
  arm64: compat: align cacheflush syscall with arch/arm
  arm64: add seccomp support
  arm64: add SIGSYS siginfo for compat task
  arm64: add seccomp syscall for compat task
  asm-generic: add generic seccomp.h for secure computing mode 1
  arm64: ptrace: allow tracer to skip a system call
  arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
  arm64: Move some head.text functions to executable section
  arm64: jump labels: NOP out NOP -> NOP replacement
  arm64: add support to dump the kernel page tables
  arm64: Add FIX_HOLE to permanent fixed addresses
  arm64: alternatives: fix pr_fmt string for consistency
  arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time
  ...
2014-12-09 13:12:47 -08:00
Ley Foon Tan
00f634bc52 asm-generic: add generic futex for !CONFIG_SMP
Follow m68k futex implementation for !CONFIG_SMP.

Signed-off-by: Ley Foon Tan <lftan@altera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2014-12-08 12:55:48 +08:00
Will Deacon
1cd076bf67 iommu: provide early initialisation hook for IOMMU drivers
IOMMU drivers must be initialised before any of their upstream devices,
otherwise the relevant iommu_ops won't be configured for the bus in
question. To solve this, a number of IOMMU drivers use initcalls to
initialise the driver before anything has a chance to be probed.

Whilst this solves the immediate problem, it leaves the job of probing
the IOMMU completely separate from the iommu_ops to configure the IOMMU,
which are called on a per-bus basis and require the driver to figure out
exactly which instance of the IOMMU is being requested. In particular,
the add_device callback simply passes a struct device to the driver,
which then has to parse firmware tables or probe buses to identify the
relevant IOMMU instance.

This patch takes the first step in addressing this problem by adding an
early initialisation pass for IOMMU drivers, giving them the ability to
store some per-instance data in their iommu_ops structure and store that
in their of_node. This can later be used when parsing OF masters to
identify the IOMMU instance in question.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-01 16:47:46 +00:00
AKASHI Takahiro
65a2ae8d5b asm-generic: add generic seccomp.h for secure computing mode 1
Those values (__NR_seccomp_*) are used solely in secure_computing()
to identify mode 1 system calls. If compat system calls have different
syscall numbers, asm/seccomp.h may override them.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:24:58 +00:00
Thomas Gleixner
926ff9ad76 asm-generic: Add msi.h
To support MSI irq domains we want a generic data structure for
allocation, but we need the option to provide an architecture specific
version of it. So instead of playing #ifdef games in linux/msi.h we
add a generic header file and let architectures decide whether to
include it or to provide their own implementation and provide the
required typedef.

I know that typedefs are not really nice, but in this case there are no
forward declarations required and it's the simplest solution.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
2014-11-23 13:01:47 +01:00
Dave Hansen
9f7789f845 asm-generic: Remove asm-generic arch_bprm_mm_init()
This is a follow-on to commit 62e88b1c00 'mm: Make
arch_unmap()/bprm_mm_init() available to all architectures'

I removed the asm-generic version of arch_unmap() in that patch,
but missed arch_bprm_mm_init().  So this broke the build for
architectures using asm-generic/mmu_context.h who actually have
an MMU.

Fixes: 62e88b1c00 'mm: Make arch_unmap()/bprm_mm_init() available to all architectures'
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141122163711.0F037EE6@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-22 21:52:08 +01:00
Dave Hansen
62e88b1c00 mm: Make arch_unmap()/bprm_mm_init() available to all architectures
The x86 MPX patch set calls arch_unmap() and arch_bprm_mm_init()
from fs/exec.c, so we need at least a stub for them in all
architectures.  They are only called under an #ifdef for
CONFIG_MMU=y, so we can at least restict this to architectures
with MMU support.

blackfin/c6x have no MMU support, so do not call arch_unmap().
They also do not include mm_hooks.h or mmu_context.h at all and
do not need to be touched.

s390, um and unicore32 do not use asm-generic/mm_hooks.h, so got
their own arch_unmap() versions.  (I also moved um's
arch_dup_mmap() to be closer to the other mm_hooks.h functions).

xtensa only includes mm_hooks when MMU=y, which should be fine
since arch_unmap() is called only from MMU=y code.

For the rest, we use the stub copies of these functions in
asm-generic/mm_hook.h.

I cross compiled defconfigs for cris (to check NOMMU) and s390
to make sure that this works.  I also checked a 64-bit build
of UML and all my normal x86 builds including PARAVIRT on and
off.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141118182350.8B4AA2C2@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-19 11:54:13 +01:00
Dave Hansen
1de4fa14ee x86, mpx: Cleanup unused bound tables
The previous patch allocates bounds tables on-demand.  As noted in
an earlier description, these can add up to *HUGE* amounts of
memory.  This has caused OOMs in practice when running tests.

This patch adds support for freeing bounds tables when they are no
longer in use.

There are two types of mappings in play when unmapping tables:
 1. The mapping with the actual data, which userspace is
    munmap()ing or brk()ing away, etc...
 2. The mapping for the bounds table *backing* the data
    (is tagged with VM_MPX, see the patch "add MPX specific
    mmap interface").

If userspace use the prctl() indroduced earlier in this patchset
to enable the management of bounds tables in kernel, when it
unmaps the first type of mapping with the actual data, the kernel
needs to free the mapping for the bounds table backing the data.
This patch hooks in at the very end of do_unmap() to do so.
We look at the addresses being unmapped and find the bounds
directory entries and tables which cover those addresses.  If
an entire table is unused, we clear associated directory entry
and free the table.

Once we unmap the bounds table, we would have a bounds directory
entry pointing at empty address space. That address space might
now be allocated for some other (random) use, and the MPX
hardware might now try to walk it as if it were a bounds table.
That would be bad.  So any unmapping of an enture bounds table
has to be accompanied by a corresponding write to the bounds
directory entry to invalidate it.  That write to the bounds
directory can fault, which causes the following problem:

Since we are doing the freeing from munmap() (and other paths
like it), we hold mmap_sem for write. If we fault, the page
fault handler will attempt to acquire mmap_sem for read and
we will deadlock.  To avoid the deadlock, we pagefault_disable()
when touching the bounds directory entry and use a
get_user_pages() to resolve the fault.

The unmapping of bounds tables happends under vm_munmap().  We
also (indirectly) call vm_munmap() to _do_ the unmapping of the
bounds tables.  We avoid unbounded recursion by disallowing
freeing of bounds tables *for* bounds tables.  This would not
occur normally, so should not have any practical impact.  Being
strict about it here helps ensure that we do not have an
exploitable stack overflow.

Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151831.E4531C4A@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 00:58:54 +01:00
Dave Hansen
fe3d197f84 x86, mpx: On-demand kernel allocation of bounds tables
This is really the meat of the MPX patch set.  If there is one patch to
review in the entire series, this is the one.  There is a new ABI here
and this kernel code also interacts with userspace memory in a
relatively unusual manner.  (small FAQ below).

Long Description:

This patch adds two prctl() commands to provide enable or disable the
management of bounds tables in kernel, including on-demand kernel
allocation (See the patch "on-demand kernel allocation of bounds tables")
and cleanup (See the patch "cleanup unused bound tables"). Applications
do not strictly need the kernel to manage bounds tables and we expect
some applications to use MPX without taking advantage of this kernel
support. This means the kernel can not simply infer whether an application
needs bounds table management from the MPX registers.  The prctl() is an
explicit signal from userspace.

PR_MPX_ENABLE_MANAGEMENT is meant to be a signal from userspace to
require kernel's help in managing bounds tables.

PR_MPX_DISABLE_MANAGEMENT is the opposite, meaning that userspace don't
want kernel's help any more. With PR_MPX_DISABLE_MANAGEMENT, the kernel
won't allocate and free bounds tables even if the CPU supports MPX.

PR_MPX_ENABLE_MANAGEMENT will fetch the base address of the bounds
directory out of a userspace register (bndcfgu) and then cache it into
a new field (->bd_addr) in  the 'mm_struct'.  PR_MPX_DISABLE_MANAGEMENT
will set "bd_addr" to an invalid address.  Using this scheme, we can
use "bd_addr" to determine whether the management of bounds tables in
kernel is enabled.

Also, the only way to access that bndcfgu register is via an xsaves,
which can be expensive.  Caching "bd_addr" like this also helps reduce
the cost of those xsaves when doing table cleanup at munmap() time.
Unfortunately, we can not apply this optimization to #BR fault time
because we need an xsave to get the value of BNDSTATUS.

==== Why does the hardware even have these Bounds Tables? ====

MPX only has 4 hardware registers for storing bounds information.
If MPX-enabled code needs more than these 4 registers, it needs to
spill them somewhere. It has two special instructions for this
which allow the bounds to be moved between the bounds registers
and some new "bounds tables".

They are similar conceptually to a page fault and will be raised by
the MPX hardware during both bounds violations or when the tables
are not present. This patch handles those #BR exceptions for
not-present tables by carving the space out of the normal processes
address space (essentially calling the new mmap() interface indroduced
earlier in this patch set.) and then pointing the bounds-directory
over to it.

The tables *need* to be accessed and controlled by userspace because
the instructions for moving bounds in and out of them are extremely
frequent. They potentially happen every time a register pointing to
memory is dereferenced. Any direct kernel involvement (like a syscall)
to access the tables would obviously destroy performance.

==== Why not do this in userspace? ====

This patch is obviously doing this allocation in the kernel.
However, MPX does not strictly *require* anything in the kernel.
It can theoretically be done completely from userspace. Here are
a few ways this *could* be done. I don't think any of them are
practical in the real-world, but here they are.

Q: Can virtual space simply be reserved for the bounds tables so
   that we never have to allocate them?
A: As noted earlier, these tables are *HUGE*. An X-GB virtual
   area needs 4*X GB of virtual space, plus 2GB for the bounds
   directory. If we were to preallocate them for the 128TB of
   user virtual address space, we would need to reserve 512TB+2GB,
   which is larger than the entire virtual address space today.
   This means they can not be reserved ahead of time. Also, a
   single process's pre-popualated bounds directory consumes 2GB
   of virtual *AND* physical memory. IOW, it's completely
   infeasible to prepopulate bounds directories.

Q: Can we preallocate bounds table space at the same time memory
   is allocated which might contain pointers that might eventually
   need bounds tables?
A: This would work if we could hook the site of each and every
   memory allocation syscall. This can be done for small,
   constrained applications. But, it isn't practical at a larger
   scale since a given app has no way of controlling how all the
   parts of the app might allocate memory (think libraries). The
   kernel is really the only place to intercept these calls.

Q: Could a bounds fault be handed to userspace and the tables
   allocated there in a signal handler instead of in the kernel?
A: (thanks to tglx) mmap() is not on the list of safe async
   handler functions and even if mmap() would work it still
   requires locking or nasty tricks to keep track of the
   allocation state there.

Having ruled out all of the userspace-only approaches for managing
bounds tables that we could think of, we create them on demand in
the kernel.

Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151829.AD4310DE@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 00:58:53 +01:00
Will Deacon
fb7332a9fe mmu_gather: move minimal range calculations into generic code
On architectures with hardware broadcasting of TLB invalidation messages
, it makes sense to reduce the range of the mmu_gather structure when
unmapping page ranges based on the dirty address information passed to
tlb_remove_tlb_entry.

arm64 already does this by directly manipulating the start/end fields
of the gather structure, but this confuses the generic code which
does not expect these fields to change and can end up calculating
invalid, negative ranges when forcing a flush in zap_pte_range.

This patch moves the minimal range calculation out of the arm64 code
and into the generic implementation, simplifying zap_pte_range in the
process (which no longer needs to care about start/end, since they will
point to the appropriate ranges already). With the range being tracked
by core code, the need_flush flag is dropped in favour of checking that
the end of the range has actually been set.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-17 10:12:42 +00:00
Jay Vosburgh
a77f9c5dcd Revert "fast_hash: avoid indirect function calls"
This reverts commit e5a2c89995.

	Commit e5a2c899 introduced an alternative_call, arch_fast_hash2,
that selects between __jhash2 and __intel_crc4_2_hash based on the
X86_FEATURE_XMM4_2.

	Unfortunately, the alternative_call system does not appear to be
suitable for use with C functions, as register usage is not handled
properly for the called functions.  The __jhash2 function in particular
clobbers registers that are not preserved when called via
alternative_call, resulting in a panic for direct callers of
arch_fast_hash2 on older CPUs lacking sse4_2.  It is possible that
__intel_crc4_2_hash works merely by chance because it uses fewer
registers.

	This commit was suggested as the source of the problem by Jesse
Gross <jesse@nicira.com>.

Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-14 16:36:25 -05:00
Arnd Bergmann
1c8d29696f Merge branch 'io' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into asm-generic
* 'io' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  documentation: memory-barriers: clarify relaxed io accessor semantics
  x86: io: implement dummy relaxed accessor macros for writes
  tile: io: implement dummy relaxed accessor macros for writes
  sparc: io: implement dummy relaxed accessor macros for writes
  powerpc: io: implement dummy relaxed accessor macros for writes
  parisc: io: implement dummy relaxed accessor macros for writes
  mn10300: io: implement dummy relaxed accessor macros for writes
  m68k: io: implement dummy relaxed accessor macros for writes
  m32r: io: implement dummy relaxed accessor macros for writes
  ia64: io: implement dummy relaxed accessor macros for writes
  cris: io: implement dummy relaxed accessor macros for writes
  frv: io: implement dummy relaxed accessor macros for writes
  xtensa: io: remove dummy relaxed accessor macros for reads
  s390: io: remove dummy relaxed accessor macros for reads
  microblaze: io: remove dummy relaxed accessor macros
  asm-generic: io: implement relaxed accessor macros as conditional wrappers

Conflicts:
	include/asm-generic/io.h

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2014-11-11 19:55:45 +01:00
Thierry Reding
9ab3a7a0d2 asm-generic/io.h: Implement generic {read,write}s*()
Currently driver writers need to use io{read,write}{8,16,32}_rep() when
accessing FIFO registers portably. This is bad for two reasons: it is
inconsistent with how other registers are accessed using the standard
{read,write}{b,w,l}() functions, which can lead to confusion. On some
architectures the io{read,write}*() functions also need to perform some
extra checks to determine whether an address is memory-mapped or refers
to I/O space. Drivers which can be expected to never use I/O can safely
use the {read,write}s{b,w,l,q}(), just like they use their non-string
variants and there's no need for these extra checks.

This patch implements generic versions of readsb(), readsw(), readsl(),
readsq(), writesb(), writesw(), writesl() and writesq(). Variants of
these string functions for I/O accesses (ins*() and outs*() as well as
ioread*_rep() and iowrite*_rep()) are now implemented in terms of the
new functions.

Going forward, {read,write}{,s}{b,w,l,q}() should be used consistently
by drivers for devices that will only ever be memory-mapped and hence
don't need to access I/O space, whereas io{read,write}{8,16,32}_rep()
should be used by drivers for devices that can be either memory-mapped
or I/O-mapped.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-10 15:59:22 +01:00