If the tick isn't stopped, the target residency of the state selected
by the menu governor may be greater than the actual time to the next
tick and that means lost energy.

To avoid that, make tick_nohz_get_sleep_length() return the current
time to the next event (before stopping the tick) in addition to the
estimated one via an extra pointer argument and make menu_select()
use that value to refine the state selection when necessary.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

In order to address the issue with short idle duration predictions
by the idle governor after the scheduler tick has been stopped,
reorder the code in cpuidle_idle_call() so that the governor idle
state selection runs before tick_nohz_idle_go_idle() and use the
"nohz" hint returned by cpuidle_select() to decide whether or not
to stop the tick.

This isn't straightforward, because menu_select() invokes
tick_nohz_get_sleep_length() to get the time to the next timer
event and the number returned by the latter comes from
__tick_nohz_idle_stop_tick().  Fortunately, however, it is possible
to compute that number without actually stopping the tick and with
the help of the existing code.

Namely, tick_nohz_get_sleep_length() can be made call
tick_nohz_next_event(), introduced earlier, to get the time to the
next non-highres timer event.  If that happens, tick_nohz_next_event()
need not be called by __tick_nohz_idle_stop_tick() again.

If it turns out that the scheduler tick cannot be stopped going
forward or the next timer event is too close for the tick to be
stopped, tick_nohz_get_sleep_length() can simply return the time to
the next event currently programmed into the corresponding clock
event device.

In addition to knowing the return value of tick_nohz_next_event(),
however, tick_nohz_get_sleep_length() needs to know the time to the
next highres timer event, but with the scheduler tick timer excluded,
which can be computed with the help of hrtimer_get_next_event().

That minimum of that number and the tick_nohz_next_event() return
value is the total time to the next timer event with the assumption
that the tick will be stopped.  It can be returned to the idle
governor which can use it for predicting idle duration (under the
assumption that the tick will be stopped) and deciding whether or
not it makes sense to stop the tick before putting the CPU into the
selected idle state.

With the above, the sleep_length field in struct tick_sched is not
necessary any more, so drop it.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199227Reported-by: Doug Smythies <dsmythies@telus.net>
Reported-by: Thomas Ilsche <thomas.ilsche@tu-dresden.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>

The next set of changes will need to compute the time to the next
hrtimer event over all hrtimers except for the scheduler tick one.

To that end introduce a new helper function,
hrtimer_next_event_without(), for computing the time until the next
hrtimer event over all timers except for one and modify the underlying
code in __hrtimer_next_event_base() to prepare it for being called by
that new function.

No intentional changes in functionality.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>

In order to address the issue with short idle duration predictions
by the idle governor after the scheduler tick has been stopped, split
tick_nohz_stop_sched_tick() into two separate routines, one computing
the time to the next timer event and the other simply stopping the
tick when the time to the next timer event is known.

Prepare these two routines to be called separately, as one of them
will be called by the idle governor in the cpuidle_select() code
path after subsequent changes.

Update the former callers of tick_nohz_stop_sched_tick() to use
the new routines, tick_nohz_next_event() and tick_nohz_stop_tick(),
instead of it and move the updates of the sleep_length field in
struct tick_sched into __tick_nohz_idle_stop_tick() as it doesn't
need to be updated anywhere else.

There should be no intentional visible changes in functionality
resulting from this change.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>

Add a new pointer argument to cpuidle_select() and to the ->select
cpuidle governor callback to allow a boolean value indicating
whether or not the tick should be stopped before entering the
selected state to be returned from there.

Make the ladder governor ignore that pointer (to preserve its
current behavior) and make the menu governor return 'false" through
it if:
 (1) the idle exit latency is constrained at 0, or
 (2) the selected state is a polling one, or
 (3) the expected idle period duration is within the tick period
     range.

In addition to that, the correction factor computations in the menu
governor need to take the possibility that the tick may not be
stopped into account to avoid artificially small correction factor
values.  To that end, add a mechanism to record tick wakeups, as
suggested by Peter Zijlstra, and use it to modify the menu_update()
behavior when tick wakeup occurs.  Namely, if the CPU is woken up by
the tick and the return value of tick_nohz_get_sleep_length() is not
within the tick boundary, the predicted idle duration is likely too
short, so make menu_update() try to compensate for that by updating
the governor statistics as though the CPU was idle for a long time.

Since the value returned through the new argument pointer of
cpuidle_select() is not used by its caller yet, this change by
itself is not expected to alter the functionality of the code.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Since the subsequent changes will need a TICK_USEC definition
analogous to TICK_NSEC, rename the existing TICK_USEC as
USER_TICK_USEC, update its users and redefine TICK_USEC
accordingly.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>

Make cpuidle_idle_call() decide whether or not to stop the tick.

First, the cpuidle_enter_s2idle() path deals with the tick (and with
the entire timekeeping for that matter) by itself and it doesn't need
the tick to be stopped beforehand.

Second, to address the issue with short idle duration predictions
by the idle governor after the tick has been stopped, it will be
necessary to change the ordering of cpuidle_select() with respect
to tick_nohz_idle_stop_tick().  To prepare for that, put a
tick_nohz_idle_stop_tick() call in the same branch in which
cpuidle_select() is called.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Push the decision whether or not to stop the tick somewhat deeper
into the idle loop.

Stopping the tick upfront leads to unpleasant outcomes in case the
idle governor doesn't agree with the nohz code on the duration of the
upcoming idle period.  Specifically, if the tick has been stopped and
the idle governor predicts short idle, the situation is bad regardless
of whether or not the prediction is accurate.  If it is accurate, the
tick has been stopped unnecessarily which means excessive overhead.
If it is not accurate, the CPU is likely to spend too much time in
the (shallow, because short idle has been predicted) idle state
selected by the governor [1].

As the first step towards addressing this problem, change the code
to make the tick stopping decision inside of the loop in do_idle().
In particular, do not stop the tick in the cpu_idle_poll() code path.
Also don't do that in tick_nohz_irq_exit() which doesn't really have
enough information on whether or not to stop the tick.

Link: https://marc.info/?l=linux-pm&m=150116085925208&w=2 # [1]
Link: https://tu-dresden.de/zih/forschung/ressourcen/dateien/projekte/haec/powernightmares.pdfSuggested-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Prepare the scheduler tick code for reworking the idle loop to
avoid stopping the tick in some cases.

The idea is to split the nohz idle entry call to decouple the idle
time stats accounting and preparatory work from the actual tick stop
code, in order to later be able to delay the tick stop once we reach
more power-knowledgeable callers.

Move away the tick_nohz_start_idle() invocation from
__tick_nohz_idle_enter(), rename the latter to
__tick_nohz_idle_stop_tick() and define tick_nohz_idle_stop_tick()
as a wrapper around it for calling it from the outside.

Make tick_nohz_idle_enter() only call tick_nohz_start_idle() instead
of calling the entire __tick_nohz_idle_enter(), add another wrapper
disabling and enabling interrupts around tick_nohz_idle_stop_tick()
and make the current callers of tick_nohz_idle_enter() call it too
to retain their current functionality.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Pull power management updates from Rafael Wysocki:
 "These update the cpuidle poll state definition to reduce excessive
  energy usage related to it, add new CPU ID to the RAPL power capping
  driver, update the ACPI system suspend code to handle some special
  cases better, extend the PM core's device links code slightly, add new
  sysfs attribute for better suspend-to-idle diagnostics and easier
  hibernation handling, update power management tools and clean up
  cpufreq quite a bit.

  Specifics:

   - Modify the cpuidle poll state implementation to prevent CPUs from
     staying in the loop in there for excessive times (Rafael Wysocki).

   - Add Intel Cannon Lake chips support to the RAPL power capping
     driver (Joe Konno).

   - Add reference counting to the device links handling code in the PM
     core (Lukas Wunner).

   - Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
     suspend code (Rafael Wysocki).

   - Allow devices to be put into deeper low-power states via ACPI if
     both _SxD and _SxW are missing (Daniel Drake).

   - Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
     keyboard wakeup issue on Asus UX331UA (Chris Chiu).

   - Prevent the PCMCIA library code from aborting suspend-to-idle due
     to noirq suspend failures resulting from incorrect assumptions
     (Rafael Wysocki).

   - Add coupled cpuidle supprt to the Exynos3250 platform (Marek
     Szyprowski).

   - Add new sysfs file to make it easier to specify the image storage
     location during hibernation (Mario Limonciello).

   - Add sysfs files for collecting suspend-to-idle usage and time
     statistics for CPU idle states (Rafael Wysocki).

   - Update the pm-graph utilities (Todd Brandt).

   - Reduce the kernel log noise related to reporting Low-power Idle
     constraings by the ACPI system suspend code (Rafael Wysocki).

   - Make it easier to distinguish dedicated wakeup IRQs in the
     /proc/interrupts output (Tony Lindgren).

   - Add the frequency table validation in cpufreq to the core and drop
     it from a number of cpufreq drivers (Viresh Kumar).

   - Drop "cooling-{min|max}-level" for CPU nodes from a couple of DT
     bindings (Viresh Kumar).

   - Clean up the CPU online error code path in the cpufreq core (Viresh
     Kumar).

   - Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
     cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian, Viresh
     Kumar).

   - Drop memory allocation error messages from a few places in cpufreq
     and cpuildle drivers (Markus Elfring)"

* tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (56 commits)
  ACPI / PM: Fix keyboard wakeup from suspend-to-idle on ASUS UX331UA
  cpufreq: CPPC: Use transition_delay_us depending transition_latency
  PM / hibernate: Change message when writing to /sys/power/resume
  PM / hibernate: Make passing hibernate offsets more friendly
  cpuidle: poll_state: Avoid invoking local_clock() too often
  PM: cpuidle/suspend: Add s2idle usage and time state attributes
  cpuidle: Enable coupled cpuidle support on Exynos3250 platform
  cpuidle: poll_state: Add time limit to poll_idle()
  cpufreq: tegra186: Don't validate the frequency table twice
  cpufreq: speedstep: Don't validate the frequency table twice
  cpufreq: sparc: Don't validate the frequency table twice
  cpufreq: sh: Don't validate the frequency table twice
  cpufreq: sfi: Don't validate the frequency table twice
  cpufreq: scpi: Don't validate the frequency table twice
  cpufreq: sc520: Don't validate the frequency table twice
  cpufreq: s3c24xx: Don't validate the frequency table twice
  cpufreq: qoirq: Don't validate the frequency table twice
  cpufreq: pxa: Don't validate the frequency table twice
  cpufreq: ppc_cbe: Don't validate the frequency table twice
  cpufreq: powernow: Don't validate the frequency table twice
  ...

Pull ACPI updates from Rafael Wysocki:
 "These update the ACPICA code in the kernel to follow upstream revision
  20180313 which includes fixes related to the so-called module-level
  AML (mostly "if" type of statements outside of any methods) that
  should improve the handling of systems that load alternative SSDTs
  depending on the current configuration, for example, and event
  handling fixes related to disabling and enabling GPEs on system
  startup and on suspend/resume.

  Moreover, the ACPICA license boilerplate is replaced with SPDX license
  IDs which alone reduces the number of lines of ACPICA code in the
  kernel quite a bit.

  Also added is a new driver for the generic ACPI Time and Alarm Device
  (TAD). At the moment it only handles the most basic capabilities of
  the TAD, however.

  In addition to that the ACPI battery driver is improved to handle
  battery thresholds on ThinkPads, among other things, some bugs are
  fixed, a new backlight quirk is added and some documentation is
  updated.

  Specifics:

   - Update the in-kernel ACPICA code to upstream revision 20180313
     including:
      * Module-level AML code handling fixes and simplifications (Bob
        Moore, Erik Schmauss).
      * Fixes and cleanups related to messaging (Bob Moore).
      * Events handling fixes related to disabling and enabling GPEs
        (Erik Schmauss).
      * Introduction of SPDX license identifiers and removal of license
        boilerplate in multiple files (Erik Schmauss).
      * Assorted fixes and cleanups (Bob Moore, Erik Schmauss, Hans de
        Goede, Seunghun Han).

   - Add new basic driver for the ACPI Time and Alarm Device (Rafael
     Wysocki).

   - Modify the ACPI battery driver to support battery thresholds on
     Lenovo ThinkPads (Ognjen Galic, Colin Ian King).

   - Avoid reporting battery capacity over 100 in the ACPI battery
     driver in some cases (Laszlo Toth).

   - Make the kernel recognize an OEM _OSI string from Dell to avoid
     power management issues with NVidia GPUs in Dell platforms (Alex
     Hung).

   - Make the PCI IRQ management code handle missing _PRS cleanly (Alex
     Hung).

   - Fix uevent notifications related to device hotplut (Lee, Chun-Yi).

   - Prevent the ACPI PAD driver from leaking memory (Lenny Szubowicz).

   - Update the ACPI CPPC library code to include subspace IDs in the
     kernel messages logged by it (George Cherian).

   - Add backlight quirk for Samsung 670Z5E (Hans de Goede).

   - Add the NFIT and HMAT tables to the list of ACPI tables that can be
     overridden via initrd (Dan Williams).

   - Fix and clean up some ACPI documentation and Kconfig help language
     (Aishwarya Pant, Randy Dunlap).

   - Replace license boilerplate with an SPDX license ID in the ACPI
     PMIC operation region handling code (Rajmohan Mani)"

* tag 'acpi-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (39 commits)
  ACPI: acpi_pad: Fix memory leak in power saving threads
  ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E
  ACPI: Add Time and Alarm Device (TAD) driver
  ACPI / scan: Send change uevent with offine environmental data
  ACPI / Kconfig: Update ACPI_PROCFS_POWER help text
  ACPI / OSI: Add OEM _OSI strings to disable NVidia RTD3
  ACPICA: Update version to 20180313
  ACPICA: Cleanup/simplify module-level code support
  ACPICA: Events: add a return on failure from acpi_hw_register_read
  ACPICA: adding SPDX headers
  ACPICA: Rename a global for clarity, no functional change
  ACPICA: macros: fix ACPI_ERROR_NAMESPACE macro
  ACPICA: Change a compile-time option to a runtime option
  ACPICA: Remove calling of _STA from acpi_get_object_info()
  ACPICA: AML Debug Object: Don't ignore output of zero-length strings
  ACPICA: Fix memory leak on unusual memory leak
  ACPICA: Events: Dispatch GPEs after enabling for the first time
  ACPICA: Events: Add parallel GPE handling support to fix potential redundant _Exx evaluations
  ACPICA: Events: Stop unconditionally clearing ACPI IRQs during suspend/resume
  ACPICA: acpi: acpica: fix acpi operand cache leak in nseval.c
  ...

Pull removal of in-kernel calls to syscalls from Dominik Brodowski:
 "System calls are interaction points between userspace and the kernel.
  Therefore, system call functions such as sys_xyzzy() or
  compat_sys_xyzzy() should only be called from userspace via the
  syscall table, but not from elsewhere in the kernel.

  At least on 64-bit x86, it will likely be a hard requirement from
  v4.17 onwards to not call system call functions in the kernel: It is
  better to use use a different calling convention for system calls
  there, where struct pt_regs is decoded on-the-fly in a syscall wrapper
  which then hands processing over to the actual syscall function. This
  means that only those parameters which are actually needed for a
  specific syscall are passed on during syscall entry, instead of
  filling in six CPU registers with random user space content all the
  time (which may cause serious trouble down the call chain). Those
  x86-specific patches will be pushed through the x86 tree in the near
  future.

  Moreover, rules on how data may be accessed may differ between kernel
  data and user data. This is another reason why calling sys_xyzzy() is
  generally a bad idea, and -- at most -- acceptable in arch-specific
  code.

  This patchset removes all in-kernel calls to syscall functions in the
  kernel with the exception of arch/. On top of this, it cleans up the
  three places where many syscalls are referenced or prototyped, namely
  kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h"

* 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits)
  bpf: whitelist all syscalls for error injection
  kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions
  kernel/sys_ni: sort cond_syscall() entries
  syscalls/x86: auto-create compat_sys_*() prototypes
  syscalls: sort syscall prototypes in include/linux/compat.h
  net: remove compat_sys_*() prototypes from net/compat.h
  syscalls: sort syscall prototypes in include/linux/syscalls.h
  kexec: move sys_kexec_load() prototype to syscalls.h
  x86/sigreturn: use SYSCALL_DEFINE0
  x86: fix sys_sigreturn() return type to be long, not unsigned long
  x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
  mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
  mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
  mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64()
  fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate()
  fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls
  fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate()
  fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall
  kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
  kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()
  ...

Commit 2a98dc02 ("include/linux/bitmap.h: turn bitmap_set and
bitmap_clear into memset when possible") introduced an optimization to
bitmap_{set,clear}() which uses memset() when the start and length are
constants aligned to a byte.

This is wrong on big-endian systems; our bitmaps are arrays of unsigned
long, so bit n is not at byte n / 8 in memory.  This was caught by the
Btrfs selftests, but the bitmap selftests also fail when run on a
big-endian machine.

We can still use memset if the start and length are aligned to an
unsigned long, so do that on big-endian.  The same problem applies to
the memcmp in bitmap_equal(), so fix it there, too.

Fixes: 2a98dc02 ("include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible")
Fixes: 2c6deb01 ("bitmap: use memcmp optimisation in more situations")
Cc: stable@kernel.org
Reported-by: "Erhard F." <erhard_f@mailbox.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pul removal of obsolete architecture ports from Arnd Bergmann:
 "This removes the entire architecture code for blackfin, cris, frv,
  m32r, metag, mn10300, score, and tile, including the associated device
  drivers.

  I have been working with the (former) maintainers for each one to
  ensure that my interpretation was right and the code is definitely
  unused in mainline kernels. Many had fond memories of working on the
  respective ports to start with and getting them included in upstream,
  but also saw no point in keeping the port alive without any users.

  In the end, it seems that while the eight architectures are extremely
  different, they all suffered the same fate: There was one company in
  charge of an SoC line, a CPU microarchitecture and a software
  ecosystem, which was more costly than licensing newer off-the-shelf
  CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
  seems that all the SoC product lines are still around, but have not
  used the custom CPU architectures for several years at this point. In
  contrast, CPU instruction sets that remain popular and have actively
  maintained kernel ports tend to all be used across multiple licensees.

  [ See the new nds32 port merged in the previous commit for the next
    generation of "one company in charge of an SoC line, a CPU
    microarchitecture and a software ecosystem"   - Linus ]

  The removal came out of a discussion that is now documented at
  https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
  marking any ports as deprecated but remove them all at once after I
  made sure that they are all unused. Some architectures (notably tile,
  mn10300, and blackfin) are still being shipped in products with old
  kernels, but those products will never be updated to newer kernel
  releases.

  After this series, we still have a few architectures without mainline
  gcc support:

   - unicore32 and hexagon both have very outdated gcc releases, but the
     maintainers promised to work on providing something newer. At least
     in case of hexagon, this will only be llvm, not gcc.

   - openrisc, risc-v and nds32 are still in the process of finishing
     their support or getting it added to mainline gcc in the first
     place. They all have patched gcc-7.3 ports that work to some
     degree, but complete upstream support won't happen before gcc-8.1.
     Csky posted their first kernel patch set last week, their situation
     will be similar

  [ Palmer Dabbelt points out that RISC-V support is in mainline gcc
    since gcc-7, although gcc-7.3.0 is the recommended minimum  - Linus ]"

This really says it all:

 2498 files changed, 95 insertions(+), 467668 deletions(-)

* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
  MAINTAINERS: UNICORE32: Change email account
  staging: iio: remove iio-trig-bfin-timer driver
  tty: hvc: remove tile driver
  tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
  serial: remove tile uart driver
  serial: remove m32r_sio driver
  serial: remove blackfin drivers
  serial: remove cris/etrax uart drivers
  usb: Remove Blackfin references in USB support
  usb: isp1362: remove blackfin arch glue
  usb: musb: remove blackfin port
  usb: host: remove tilegx platform glue
  pwm: remove pwm-bfin driver
  i2c: remove bfin-twi driver
  spi: remove blackfin related host drivers
  watchdog: remove bfin_wdt driver
  can: remove bfin_can driver
  mmc: remove bfin_sdh driver
  input: misc: remove blackfin rotary driver
  input: keyboard: remove bf54x driver
  ...

Pull nds32 architecture support from Greentime Hu:
 "This contains the core nds32 Linux port (including interrupt
  controller driver and timer driver), which has been through seven
  rounds of review on mailing list.

  It is able to boot to shell and passes most LTP-2017 testsuites in
  nds32 AE3XX platform:

    Total Tests: 1901
    Total Skipped Tests: 618
    Total Failures: 78"
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

* tag 'nds32-for-linus-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux: (44 commits)
  nds32: To use the generic dump_stack()
  nds32: fix building failed if using elf toolchain.
  nios2: add ioremap_nocache declaration before include asm-generic/io.h.
  nds32: fix building failed if using older version gcc.
  dt-bindings: timer: Add andestech atcpit100 timer binding doc
  clocksource/drivers/atcpit100: VDSO support
  clocksource/drivers/atcpit100: Add andestech atcpit100 timer
  net: faraday add nds32 support.
  irqchip: Andestech Internal Vector Interrupt Controller driver
  dt-bindings: interrupt-controller: Andestech Internal Vector Interrupt Controller
  dt-bindings: nds32 SoC Bindings
  dt-bindings: nds32 L2 cache controller Bindings
  dt-bindings: nds32 CPU Bindings
  MAINTAINERS: Add nds32
  nds32: Build infrastructure
  nds32: defconfig
  nds32: Miscellaneous header files
  nds32: Device tree support
  nds32: Generic timers support
  nds32: Loadable modules
  ...

Pull m68k updates from Geert Uytterhoeven:

 - Macintosh enhancements and fixes

 - Remove useless memory layout printing using hashed pointers

 - Add missing Amiga Zorro bus DMA mask

 - Small fixes and cleanups

 - Defconfig updates

* tag 'm68k-for-v4.17-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k/mac: Remove bogus "FIXME" comment
  m68k/mac: Enable RTC for 100-series PowerBooks
  m68k/mac: Clean up whitespace and remove redundant parentheses
  m68k/defconfig: Update defconfigs for v4.16-rc5
  zorro: Set up z->dev.dma_mask for the DMA API
  m68k/time: Stop validating rtc_time in .read_time
  m68k/mm: Stop printing the virtual memory layout
  macintosh/via-pmu68k: Initialize PMU driver with setup_arch and arch_initcall
  m68k/mac: Fix apparent race condition in Baboon interrupt dispatch
  m68k/mac: Enable PDMA support for PowerBook 190

Pull EFI updates from Ingo Molnar:
 "The main EFI changes in this cycle were:

   - Fix the apple-properties code (Andy Shevchenko)

   - Add WARN() on arm64 if UEFI Runtime Services corrupt the reserved
     x18 register (Ard Biesheuvel)

   - Use efi_switch_mm() on x86 instead of manipulating %cr3 directly
     (Sai Praneeth)

   - Fix early memremap leak in ESRT code (Ard Biesheuvel)

   - Switch to L"xxx" notation for wide string literals (Ard Biesheuvel)

   - ... plus misc other cleanups and bugfixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Use efi_switch_mm() rather than manually twiddling with %cr3
  x86/efi: Replace efi_pgd with efi_mm.pgd
  efi: Use string literals for efi_char16_t variable initializers
  efi/esrt: Fix handling of early ESRT table mapping
  efi: Use efi_mm in x86 as well as ARM
  efi: Make const array 'apple' static
  efi/apple-properties: Use memremap() instead of ioremap()
  efi: Reorder pr_notice() with add_device_randomness() call
  x86/efi: Replace GFP_ATOMIC with GFP_KERNEL in efi_query_variable_store()
  efi/arm64: Check whether x18 is preserved by runtime services calls
  efi/arm*: Stop printing addresses of virtual mappings
  efi/apple-properties: Remove redundant attribute initialization from unmarshal_key_value_pairs()
  efi/arm*: Only register page tables when they exist

Pull x86 dma mapping updates from Ingo Molnar:
 "This tree, by Christoph Hellwig, switches over the x86 architecture to
  the generic dma-direct and swiotlb code, and also unifies more of the
  dma-direct code between architectures. The now unused x86-only
  primitives are removed"

* 'x86-dma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  dma-mapping: Don't clear GFP_ZERO in dma_alloc_attrs
  swiotlb: Make swiotlb_{alloc,free}_buffer depend on CONFIG_DMA_DIRECT_OPS
  dma/swiotlb: Remove swiotlb_{alloc,free}_coherent()
  dma/direct: Handle force decryption for DMA coherent buffers in common code
  dma/direct: Handle the memory encryption bit in common code
  dma/swiotlb: Remove swiotlb_set_mem_attributes()
  set_memory.h: Provide set_memory_{en,de}crypted() stubs
  x86/dma: Remove dma_alloc_coherent_gfp_flags()
  iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and clean up intel_{alloc,free}_coherent()
  iommu/amd_iommu: Use CONFIG_DMA_DIRECT_OPS=y and dma_direct_{alloc,free}()
  x86/dma/amd_gart: Use dma_direct_{alloc,free}()
  x86/dma/amd_gart: Look at dev->coherent_dma_mask instead of GFP_DMA
  x86/dma: Use generic swiotlb_ops
  x86/dma: Use DMA-direct (CONFIG_DMA_DIRECT_OPS=y)
  x86/dma: Remove dma_alloc_coherent_mask()

Pull wait_var_event updates from Ingo Molnar:
 "This introduces the new wait_var_event() API, which is a more flexible
  waiting primitive than wait_on_atomic_t().

  All wait_on_atomic_t() users are migrated over to the new API and
  wait_on_atomic_t() is removed. The migration fixes one bug and should
  result in no functional changes for the other usecases"

* 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/wait: Improve __var_waitqueue() code generation
  sched/wait: Remove the wait_on_atomic_t() API
  sched/wait, arch/mips: Fix and convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/ocfs2: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/fscache: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/btrfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/afs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/media: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/drm: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait: Introduce wait_var_event()

Pull x86 timer updates from Ingo Molnar:
 "Two changes: add the new convert_art_ns_to_tsc() API for upcoming
  Intel Goldmont+ drivers, and remove the obsolete rdtscll() API"

* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tsc: Get rid of rdtscll()
  x86/tsc: Convert ART in nanoseconds to TSC

Pull x86 platform updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add "Jailhouse" hypervisor support (Jan Kiszka)

   - Update DeviceTree support (Ivan Gorinov)

   - Improve DMI date handling (Andy Shevchenko)"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/PCI: Fix a potential regression when using dmi_get_bios_year()
  firmware/dmi_scan: Uninline dmi_get_bios_year() helper
  x86/devicetree: Use CPU description from Device Tree
  of/Documentation: Specify local APIC ID in "reg"
  MAINTAINERS: Add entry for Jailhouse
  x86/jailhouse: Allow to use PCI_MMCONFIG without ACPI
  x86: Consolidate PCI_MMCONFIG configs
  x86: Align x86_64 PCI_MMCONFIG with 32-bit variant
  x86/jailhouse: Enable PCI mmconfig access in inmates
  PCI: Scan all functions when running over Jailhouse
  jailhouse: Provide detection for non-x86 systems
  x86/devicetree: Fix device IRQ settings in DT
  x86/devicetree: Initialize device tree before using it
  pci: Simplify code by using the new dmi_get_bios_year() helper
  ACPI/sleep: Simplify code by using the new dmi_get_bios_year() helper
  x86/pci: Simplify code by using the new dmi_get_bios_year() helper
  dmi: Introduce the dmi_get_bios_year() helper function
  x86/platform/quark: Re-use DEFINE_SHOW_ATTRIBUTE() macro
  x86/platform/atom: Re-use DEFINE_SHOW_ATTRIBUTE() macro

Pull x86 mm updates from Ingo Molnar:

 - Extend the memmap= boot parameter syntax to allow the redeclaration
   and dropping of existing ranges, and to support all e820 range types
   (Jan H. Schönherr)

 - Improve the W+X boot time security checks to remove false positive
   warnings on Xen (Jan Beulich)

 - Support booting as Xen PVH guest (Juergen Gross)

 - Improved 5-level paging (LA57) support, in particular it's possible
   now to have a single kernel image for both 4-level and 5-level
   hardware (Kirill A. Shutemov)

 - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky)

 - Preparatory commits for hardware-encrypted RAM support on Intel CPUs.
   (Kirill A. Shutemov)

 - Improved Intel-MID support (Andy Shevchenko)

 - Show EFI page tables in page_tables debug files (Andy Lutomirski)

 - ... plus misc fixes and smaller cleanups

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  x86/cpu/tme: Fix spelling: "configuation" -> "configuration"
  x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
  x86/mm: Update comment in detect_tme() regarding x86_phys_bits
  x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic
  x86/mm: Remove pointless checks in vmalloc_fault
  x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms
  ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback
  ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export
  x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf
  x86/pconfig: Detect PCONFIG targets
  x86/tme: Detect if TME and MKTME is activated by BIOS
  x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G
  x86/boot/compressed/64: Use page table in trampoline memory
  x86/boot/compressed/64: Use stack from trampoline memory
  x86/boot/compressed/64: Make sure we have a 32-bit code segment
  x86/mm: Do not use paravirtualized calls in native_set_p4d()
  kdump, vmcoreinfo: Export pgtable_l5_enabled value
  x86/boot/compressed/64: Prepare new top-level page table for trampoline
  x86/boot/compressed/64: Set up trampoline memory
  x86/boot/compressed/64: Save and restore trampoline memory
  ...

Pull x86 cleanups and msr updates from Ingo Molnar:
 "The main change is a performance/latency improvement to /dev/msr
  access. The rest are misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msr: Make rdmsrl_safe_on_cpu() scheduling safe as well
  x86/cpuid: Allow cpuid_read() to schedule
  x86/msr: Allow rdmsr_safe_on_cpu() to schedule
  x86/rtc: Stop using deprecated functions
  x86/dumpstack: Unify show_regs()
  x86/fault: Do not print IP in show_fault_oops()
  x86/MSR: Move native_* variants to msr.h

Pull x86 build updates from Ingo Molnar:
 "The biggest change is the forcing of asm-goto support on x86, which
  effectively increases the GCC minimum supported version to gcc-4.5 (on
  x86)"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build: Don't pass in -D__KERNEL__ multiple times
  x86: Remove FAST_FEATURE_TESTS
  x86: Force asm-goto
  x86/build: Drop superfluous ALIGN from the linker script

Pull x86 asm fixlets from Ingo Molnar:
 "A clobber list fix and cleanups"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Trim clear_page.S includes
  x86/asm: Clobber flags in clear_page()

Pull x86 apic updates from Ingo Molnar:
 "The main x86 APIC/IOAPIC changes in this cycle were:

   - Robustify kexec support to more carefully restore IRQ hardware
     state before calling into kexec/kdump kernels. (Baoquan He)

   - Clean up the local APIC code a bit (Dou Liyang)

   - Remove unused callbacks (David Rientjes)"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Finish removing unused callbacks
  x86/apic: Drop logical_smp_processor_id() inline
  x86/apic: Modernize the pending interrupt code
  x86/apic: Move pending interrupt check code into it's own function
  x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified
  x86/apic: Rename variables and functions related to x86_io_apic_ops
  x86/apic: Remove the (now) unused disable_IO_APIC() function
  x86/apic: Fix restoring boot IRQ mode in reboot and kexec/kdump
  x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=y
  x86/apic: Split out restore_boot_irq_mode() from disable_IO_APIC()
  x86/apic: Make setup_local_APIC() static
  x86/apic: Simplify init_bsp_APIC() usage
  x86/x2apic: Mark set_x2apic_phys_mode() as __init

Pull SMP hotplug updates from Ingo Molnar:
 "Simplify the CPU hot-plug state machine"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Fix unused function warning
  cpu/hotplug: Merge cpuhp_bp_states and cpuhp_ap_states

Pull scheduler updates from Ingo Molnar:
 "The main scheduler changes in this cycle were:

   - NUMA balancing improvements (Mel Gorman)

   - Further load tracking improvements (Patrick Bellasi)

   - Various NOHZ balancing cleanups and optimizations (Peter Zijlstra)

   - Improve blocked load handling, in particular we can now reduce and
     eventually stop periodic load updates on 'very idle' CPUs. (Vincent
     Guittot)

   - On isolated CPUs offload the final 1Hz scheduler tick as well, plus
     related cleanups and reorganization. (Frederic Weisbecker)

   - Core scheduler code cleanups (Ingo Molnar)"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  sched/core: Update preempt_notifier_key to modern API
  sched/cpufreq: Rate limits for SCHED_DEADLINE
  sched/fair: Update util_est only on util_avg updates
  sched/cpufreq/schedutil: Use util_est for OPP selection
  sched/fair: Use util_est in LB and WU paths
  sched/fair: Add util_est on top of PELT
  sched/core: Remove TASK_ALL
  sched/completions: Use bool in try_wait_for_completion()
  sched/fair: Update blocked load when newly idle
  sched/fair: Move idle_balance()
  sched/nohz: Merge CONFIG_NO_HZ_COMMON blocks
  sched/fair: Move rebalance_domains()
  sched/nohz: Optimize nohz_idle_balance()
  sched/fair: Reduce the periodic update duration
  sched/nohz: Stop NOHZ stats when decayed
  sched/cpufreq: Provide migration hint
  sched/nohz: Clean up nohz enter/exit
  sched/fair: Update blocked load from NEWIDLE
  sched/fair: Add NOHZ stats balancing
  sched/fair: Restructure nohz_balance_kick()
  ...

Pull x86 RAS updates from Ingo Molnar:
 "The main changes in this cycle were:

   - AMD MCE support/decoding improvements (Yazen Ghannam)

   - general MCE header cleanups and reorganization (Borislav Petkov)"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "x86/mce/AMD: Collect error info even if valid bits are not set"
  x86/MCE: Cleanup and complete struct mce fields definitions
  x86/mce/AMD: Carve out SMCA get_block_address() code
  x86/mce/AMD: Get address from already initialized block
  x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type
  x86/mce/AMD: Pass the bank number to smca_get_bank_type()
  x86/mce/AMD: Collect error info even if valid bits are not set
  x86/mce: Issue the 'mcelog --ascii' message only on !AMD
  x86/mce: Convert 'struct mca_config' bools to a bitfield
  x86/mce: Put private structures and definitions into the internal header

Error injection is a useful mechanism to fail arbitrary kernel
functions. However, it is often hard to guarantee an error propagates
appropriately to user space programs. By injecting into syscalls, we can
return arbitrary values to user space directly; this increases
flexibility and robustness in testing, allowing us to test user space
error paths effectively.

The following script, for example, fails calls to sys_open() from a
given pid:

from bcc import BPF
from sys import argv

pid = argv[1]

prog = r"""

int kprobe__SyS_open(struct pt_regs *ctx, const char *pathname, int flags)
{
    u32 pid = bpf_get_current_pid_tgid();
    if (pid == %s)
        bpf_override_return(ctx, -ENOMEM);
    return 0;
}
""" % pid

b = BPF(text=prog)
while 1:
    b.perf_buffer_poll()

This patch whitelists all syscalls defined with SYSCALL_DEFINE and
COMPAT_SYSCALL_DEFINE for error injection. These changes are not
intended to be considered stable, and would normally be configured off.
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

This keeps it in line with the SYSCALL_DEFINEx() / COMPAT_SYSCALL_DEFINEx()
calling convention.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

Shuffle the cond_syscall() entries in kernel/sys_ni.c around so that they
are kept in the same order as in include/uapi/asm-generic/unistd.h. For
better structuring, add the same comments as in that file, but keep a few
additional comments and extend the commentary where it seems useful.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

compat_sys_*() functions are no longer called from within the kernel on
x86 except from the system call table. Linking the system call does not
require compat_sys_*() function prototypes at least on x86. Therefore,
generate compat_sys_*() prototypes on-the-fly within the
COMPAT_SYSCALL_DEFINEx() macro, and remove x86-specific prototypes from
various header files.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: x86@kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

Shuffle the syscall prototypes in include/linux/compat.h around so
that they are kept in the same order as in
include/uapi/asm-generic/unistd.h. The individual entries are kept
the same, and neither modified to bring them in line with kernel coding
style nor wrapped in proper ifdefs -- as an exception to this, add the
prefix "asmlinkage" where it was missing.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

As the syscall functions should only be called from the system call table
but not from elsewhere in the kernel, it is sufficient that they are
defined in linux/compat.h.

Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

Shuffle the syscall prototypes in include/linux/syscalls.h around so
that they are kept in the same order as in
include/uapi/asm-generic/unistd.h. The individual entries are kept
the same, and neither modified to bring them in line with kernel coding
style nor wrapped in proper ifdefs.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

As the syscall function should only be called from the system call table
but not from elsewhere in the kernel, move the prototype for
sys_kexec_load() to include/syscall.h.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

All definitions of syscalls in x86 except for those patched here have
already been using the appropriate SYSCALL_DEFINE*.
Signed-off-by: Michael Tautschnig <tautschn@amazon.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jaswinder Singh <jaswinder@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: x86@kernel.org
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

Same as with other system calls, sys_sigreturn() should return a value
of type long, not unsigned long. This also matches the behaviour for
IA32_EMULATION, see sys32_sigreturn() in arch/x86/ia32/ia32_signal.c .

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: x86@kernel.org
Cc: Michael Tautschnig <tautschn@amazon.co.uk>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

Using this helper allows us to avoid the in-kernel calls to the
sys_ioperm() syscall. The ksys_ prefix denotes that this function is meant
as a drop-in replacement for the syscall. In particular, it uses the same
calling convention as sys_ioperm().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: x86@kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>