This updates the ptrace code to use ppc_breakpoint_available().

We now advertise via PPC_PTRACE_GETHWDBGINFO zero breakpoints when the
DAWR is missing (ie. POWER9). This results in GDB falling back to
software emulation of the breakpoint (which is slow).

For the features advertised by PPC_PTRACE_GETHWDBGINFO, we keep
advertising DAWR as if we don't GDB assumes 1 breakpoint irrespective
of the number of breakpoints advertised. GDB then fails later when
trying to set this one breakpoint.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Add ppc_breakpoint_available() to determine if a breakpoint is
available currently via the DAWR or DABR.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This works around a hardware bug in "Nimbus" POWER9 DD2.2 processors,
where the contents of the TEXASR can get corrupted while a thread is
in fake suspend state.  The workaround is for the instruction emulation
code to use the value saved at the most recent guest exit in real
suspend mode.  We achieve this by simply not saving the TEXASR into
the vcpu struct on an exit in fake suspend state.  We also have to
take care to set the orig_texasr field only on guest exit in real
suspend state.

This also means that on guest entry in fake suspend state, TEXASR
will be restored to the value it had on the last exit in real suspend
state, effectively counteracting any hardware-caused corruption.  This
works because TEXASR may not be written in suspend state.

With this, the guest might see the wrong values in TEXASR if it reads
it while in suspend state, but will see the correct value in
non-transactional state (e.g. after a treclaim), and treclaim will
work correctly.

With this workaround, the code will actually run slightly faster, and
will operate correctly on systems without the TEXASR bug (since TEXASR
may not be written in suspend state, and is only changed by failure
recording, which will have already been done before we get into fake
suspend state).  Therefore these changes are not made subject to a CPU
feature bit.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This works around a hardware bug in "Nimbus" POWER9 DD2.2 processors,
where a treclaim performed in fake suspend mode can cause subsequent
reads from the XER register to return inconsistent values for the SO
(summary overflow) bit.  The inconsistent SO bit state can potentially
be observed on any thread in the core.  We have to do the treclaim
because that is the only way to get the thread out of suspend state
(fake or real) and into non-transactional state.

The workaround for the bug is to force the core into SMT4 mode before
doing the treclaim.  This patch adds the code to do that, conditional
on the CPU_FTR_P9_TM_XER_SO_BUG feature bit.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

POWER9 has hardware bugs relating to transactional memory and thread
reconfiguration (changes to hardware SMT mode).  Specifically, the core
does not have enough storage to store a complete checkpoint of all the
architected state for all four threads.  The DD2.2 version of POWER9
includes hardware modifications designed to allow hypervisor software
to implement workarounds for these problems.  This patch implements
those workarounds in KVM code so that KVM guests see a full, working
transactional memory implementation.

The problems center around the use of TM suspended state, where the
CPU has a checkpointed state but execution is not transactional.  The
workaround is to implement a "fake suspend" state, which looks to the
guest like suspended state but the CPU does not store a checkpoint.
In this state, any instruction that would cause a transition to
transactional state (rfid, rfebb, mtmsrd, tresume) or would use the
checkpointed state (treclaim) causes a "soft patch" interrupt (vector
0x1500) to the hypervisor so that it can be emulated.  The trechkpt
instruction also causes a soft patch interrupt.

On POWER9 DD2.2, we avoid returning to the guest in any state which
would require a checkpoint to be present.  The trechkpt in the guest
entry path which would normally create that checkpoint is replaced by
either a transition to fake suspend state, if the guest is in suspend
state, or a rollback to the pre-transactional state if the guest is in
transactional state.  Fake suspend state is indicated by a flag in the
PACA plus a new bit in the PSSCR.  The new PSSCR bit is write-only and
reads back as 0.

On exit from the guest, if the guest is in fake suspend state, we still
do the treclaim instruction as we would in real suspend state, in order
to get into non-transactional state, but we do not save the resulting
register state since there was no checkpoint.

Emulation of the instructions that cause a softpatch interrupt is
handled in two paths.  If the guest is in real suspend mode, we call
kvmhv_p9_tm_emulation_early() to handle the cases where the guest is
transitioning to transactional state.  This is called before we do the
treclaim in the guest exit path; because we haven't done treclaim, we
can get back to the guest with the transaction still active.  If the
instruction is a case that kvmhv_p9_tm_emulation_early() doesn't
handle, or if the guest is in fake suspend state, then we proceed to
do the complete guest exit path and subsequently call
kvmhv_p9_tm_emulation() in host context with the MMU on.  This handles
all the cases including the cases that generate program interrupts
(illegal instruction or TM Bad Thing) and facility unavailable
interrupts.

The emulation is reasonably straightforward and is mostly concerned
with checking for exception conditions and updating the state of
registers such as MSR and CR0.  The treclaim emulation takes care to
ensure that the TEXASR register gets updated as if it were the guest
treclaim instruction that had done failure recording, not the treclaim
done in hypervisor state in the guest exit path.

With this, the KVM_CAP_PPC_HTM capability returns true (1) even if
transactional memory is not available to host userspace.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

POWER9 processors up to and including "Nimbus" v2.2 have hardware
bugs relating to transactional memory and thread reconfiguration.
One of these bugs has a workaround which is to get the core into
SMT4 state temporarily.  This workaround is only needed when
running bare-metal.

This patch provides a function which gets the core into SMT4 mode
by preventing threads from going to a stop state, and waking up
those which are already in a stop state.  Once at least 3 threads
are not in a stop state, the core will be in SMT4 and we can
continue.

To do this, we add a "dont_stop" flag to the paca to tell the
thread not to go into a stop state.  If this flag is set,
power9_idle_stop() just returns immediately with a return value
of 0.  The pnv_power9_force_smt4_catch() function does the following:

1. Set the dont_stop flag for each thread in the core, except
   ourselves (in fact we use an atomic_inc() in case more than
   one thread is calling this function concurrently).
2. See how many threads are awake, indicated by their
   requested_psscr field in the paca being 0.  If this is at
   least 3, skip to step 5.
3. Send a doorbell interrupt to each thread that was seen as
   being in a stop state in step 2.
4. Until at least 3 threads are awake, scan the threads to which
   we sent a doorbell interrupt and check if they are awake now.

This relies on the following properties:

- Once dont_stop is non-zero, requested_psccr can't go from zero to
  non-zero, except transiently (and without the thread doing stop).
- requested_psscr being zero guarantees that the thread isn't in
  a state-losing stop state where thread reconfiguration could occur.
- Doing stop with a PSSCR value of 0 won't be a state-losing stop
  and thus won't allow thread reconfiguration.
- Once threads_per_core/2 + 1 (i.e. 3) threads are awake, the core
  must be in SMT4 mode, since SMT modes are powers of 2.

This does add a sync to power9_idle_stop(), which is necessary to
provide the correct ordering between setting requested_psscr and
checking dont_stop.  The overhead of the sync should be unnoticeable
compared to the latency of going into and out of a stop state.

Because some objected to incurring this extra latency on systems where
the XER[SO] bug is not relevant, I have put the test in
power9_idle_stop inside a feature section.  This means that
pnv_power9_force_smt4_catch() WILL NOT WORK correctly on systems
without the CPU_FTR_P9_TM_XER_SO_BUG feature bit set, and will
probably hang the system.

In order to cater for uses where the caller has an operation that
has to be done while the core is in SMT4, the core continues to be
kept in SMT4 after pnv_power9_force_smt4_catch() function returns,
until the pnv_power9_force_smt4_release() function is called.
It undoes the effect of step 1 above and allows the other threads
to go into a stop state.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This adds a CPU feature bit which is set for POWER9 "Nimbus" DD2.2
processors which will be used to enable the hypervisor to assist
hardware with the handling of checkpointed register values while the
CPU is in suspend state, in order to work around hardware bugs.  The
hardware assistance for these workarounds introduced a new hardware
bug relating to the XER[SO] bit.  We add a separate feature bit for
this bug in case future chips fix it while still requiring the
hypervisor assistance with suspend state.

When the dt_cpu_ftrs subsystem is in use, the software assistance can
be enabled using a "tm-suspend-hypervisor-assist" node in the device
tree, and a "tm-suspend-xer-so-bug" node enables the workarounds for
the XER[SO] bug.  In the absence of such nodes, a quirk enables both
for POWER9 "Nimbus" DD2.2 processors.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This moves all the CPU feature bits that are only used on 32-bit
machines to the top 20 bits of the CPU feature word and arranges
for them to be defined only in 32-bit builds.  The features that
are common to 32-bit and 64-bit machines are moved to bits 0-11
of the CPU feature word.  This means that for 64-bit platforms,
bits 44-63 can now be used for new features that only exist on
64-bit machines.  (These bit numbers are counting from the right,
i.e. the LSB is bit 0.)

Because CPU_FTR_L3_DISABLE_NAP moved from the low 16 bits to the high
16 bits, we have to adjust some assembly code.  Also, CPU_FTR_EMB_HV
moved from the high 16 bits to the low 16 bits.

Note that CPU_FTR_REAL_LE only applies to 64-bit chips, because only
64-bit chips (POWER6, 7, 8, 9) have a true little-endian mode that is
a CPU execution mode as opposed to being a page attribute.

With this we now have 20 free CPU feature bits on 64-bit machines.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The CPU_FTR_L2CSR bit is never tested anywhere, so let's reclaim the
bit.

The last usage was removed in 86d63363 ("powerpc/e500mc: Remove
dead L2 flushing code in idle_e500.S") (Jun 2015).
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

All PowerPC CPUs other than the original PPC601 have a timebase
register rather than the "real-time clock" (RTC) register that the
PPC601 (and the original POWER and POWER2 CPUs) had.  Currently
we have a CPU feature bit to indicate the presence of the timebase,
but it makes more sense to use a bit to indicate the unusual
situation rather than the common situation.  This therefore defines
a CPU_FTR_USE_RTC bit in place of the CPU_FTR_USE_TB bit, and
arranges for it to be set on PPC601 systems.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

except, again, POLLFREE and POLL_BUSY_LOOP.

With this, we finally get to the promised end result:

 - POLL{IN,OUT,...} are plain integers and *not* in __poll_t, so any
   stray instances of ->poll() still using those will be caught by
   sparse.

 - eventpoll.c and select.c warning-free wrt __poll_t

 - no more kernel-side definitions of POLL... - userland ones are
   visible through the entire kernel (and used pretty much only for
   mangle/demangle)

 - same behavior as after the first series (i.e. sparc et.al. epoll(2)
   working correctly).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more poll annotation updates from Al Viro:
 "This is preparation to solving the problems you've mentioned in the
  original poll series.

  After this series, the kernel is ready for running

      for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
            L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
            for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
      done

  as a for bulk search-and-replace.

  After that, the kernel is ready to apply the patch to unify
  {de,}mangle_poll(), and then get rid of kernel-side POLL... uses
  entirely, and we should be all done with that stuff.

  Basically, that's what you suggested wrt KPOLL..., except that we can
  use EPOLL... instead - they already are arch-independent (and equal to
  what is currently kernel-side POLL...).

  After the preparations (in this series) switch to returning EPOLL...
  from ->poll() instances is completely mechanical and kernel-side
  POLL... can go away. The last step (killing kernel-side POLL... and
  unifying {de,}mangle_poll() has to be done after the
  search-and-replace job, since we need userland-side POLL... for
  unified {de,}mangle_poll(), thus the cherry-pick at the last step.

  After that we will have:

   - POLL{IN,OUT,...} *not* in __poll_t, so any stray instances of
     ->poll() still using those will be caught by sparse.

   - eventpoll.c and select.c warning-free wrt __poll_t

   - no more kernel-side definitions of POLL... - userland ones are
     visible through the entire kernel (and used pretty much only for
     mangle/demangle)

   - same behavior as after the first series (i.e. sparc et.al. epoll(2)
     working correctly)"

* 'work.poll2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  annotate ep_scan_ready_list()
  ep_send_events_proc(): return result via esed->res
  preparation to switching ->poll() to returning EPOLL...
  add EPOLLNVAL, annotate EPOLL... and event_poll->event
  use linux/poll.h instead of asm/poll.h
  xen: fix poll misannotation
  smc: missing poll annotations

Pull xtense fix from Max Filippov:
 "Build fix for xtensa architecture with KASAN enabled"

* tag 'xtensa-20180211' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: fix build with KASAN

Pull nios2 update from Ley Foon Tan:

 - clean up old Kconfig options from defconfig

 - remove leading 0x and 0s from bindings notation in dts files

* tag 'nios2-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2:
  nios2: defconfig: Cleanup from old Kconfig options
  nios2: dts: Remove leading 0x and 0s from bindings notation

The commit 917538e2 ("kasan: clean up KASAN_SHADOW_SCALE_SHIFT
usage") removed KASAN_SHADOW_SCALE_SHIFT definition from
include/linux/kasan.h and added it to architecture-specific headers,
except for xtensa. This broke the xtensa build with KASAN enabled.
Define KASAN_SHADOW_SCALE_SHIFT in arch/xtensa/include/asm/kasan.h

Reported by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 917538e2 ("kasan: clean up KASAN_SHADOW_SCALE_SHIFT usage")
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Remove old, dead Kconfig option INET_LRO. It is gone since
commit 7bbf3cae ("ipv4: Remove inet_lro library").
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>

Improve the DTS files by removing all the leading "0x" and zeros to fix the
following dtc warnings:

Warning (unit_address_format): Node /XXX unit name should not have leading "0x"

and

Warning (unit_address_format): Node /XXX unit name should not have leading 0s

Converted using the following command:

find . -type f \( -iname *.dts -o -iname *.dtsi \) -exec sed -E -i -e "s/@0x([0-9a-fA-F\.]+)\s?\{/@\L\1 \{/g" -e "s/@0+([0-9a-fA-F\.]+)\s?\{/@\L\1 \{/g" {} +

For simplicity, two sed expressions were used to solve each warnings separately.

To make the regex expression more robust a few other issues were resolved,
namely setting unit-address to lower case, and adding a whitespace before the
the opening curly brace:

https://elinux.org/Device_Tree_Linux#Linux_conventions

This is a follow up to commit 4c9847b7 ("dt-bindings: Remove leading 0x from bindings notation")
Reported-by: David Daney <ddaney@caviumnetworks.com>
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>

Pull PCI fix from Bjorn Helgaas:
 "Fix a POWER9/powernv INTx regression from the merge window (Alexey
  Kardashevskiy)"

* tag 'pci-v4.16-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  powerpc/pci: Fix broken INTx configuration via OF

Pull block fixes from Jens Axboe:
 "A few fixes to round off the merge window on the block side:

   - a set of bcache fixes by way of Michael Lyle, from the usual bcache
     suspects.

   - add a simple-to-hook-into function for bpf EIO error injection.

   - fix blk-wbt that mischarectized flushes as reads. Improve the logic
     so that flushes and writes are accounted as writes, and only reads
     as reads. From me.

   - fix requeue crash in BFQ, from Paolo"

* tag 'for-linus-20180210' of git://git.kernel.dk/linux-block:
  block, bfq: add requeue-request hook
  bcache: fix for data collapse after re-attaching an attached device
  bcache: return attach error when no cache set exist
  bcache: set writeback_rate_update_seconds in range [1, 60] seconds
  bcache: fix for allocator and register thread race
  bcache: set error_limit correctly
  bcache: properly set task state in bch_writeback_thread()
  bcache: fix high CPU occupancy during journal
  bcache: add journal statistic
  block: Add should_fail_bio() for bpf error injection
  blk-wbt: account flush requests correctly

Pull x86 platform driver updates from Darren Hart:
 "Mellanox fixes and new system type support.

  Mostly data for new system types with a correction and an
  uninitialized variable fix"

[ Pulling from github because git.infradead.org currently seems to be
  down for some reason, but Darren had a backup location    - Linus ]

* tag 'platform-drivers-x86-v4.16-3' of git://github.com/dvhart/linux-pdx86:
  platform/x86: mlx-platform: Add support for new 200G IB and Ethernet systems
  platform/x86: mlx-platform: Add support for new msn201x system type
  platform/x86: mlx-platform: Add support for new msn274x system type
  platform/x86: mlx-platform: Fix power cable setting for msn21xx family
  platform/x86: mlx-platform: Add define for the negative bus
  platform/x86: mlx-platform: Use defines for bus assignment
  platform/mellanox: mlxreg-hotplug: Fix uninitialized variable

Merge tag 'chrome-platform-for-linus-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bleung/chrome-platform

Pull chrome platform updates from Benson Leung:

 - move cros_ec_dev to drivers/mfd

 - other small maintenance fixes

[ The cros_ec_dev movement came in earlier through the MFD tree  - Linus ]

* tag 'chrome-platform-for-linus-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bleung/chrome-platform:
  platform/chrome: Use proper protocol transfer function
  platform/chrome: cros_ec_lpc: Add support for Google Glimmer
  platform/chrome: cros_ec_lpc: Register the driver if ACPI entry is missing.
  platform/chrome: cros_ec_lpc: remove redundant pointer request
  cros_ec: fix nul-termination for firmware build info
  platform/chrome: chromeos_laptop: make chromeos_laptop const

Pull KVM updates from Radim Krčmář:
 "ARM:

   - icache invalidation optimizations, improving VM startup time

   - support for forwarded level-triggered interrupts, improving
     performance for timers and passthrough platform devices

   - a small fix for power-management notifiers, and some cosmetic
     changes

  PPC:

   - add MMIO emulation for vector loads and stores

   - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
     requiring the complex thread synchronization of older CPU versions

   - improve the handling of escalation interrupts with the XIVE
     interrupt controller

   - support decrement register migration

   - various cleanups and bugfixes.

  s390:

   - Cornelia Huck passed maintainership to Janosch Frank

   - exitless interrupts for emulated devices

   - cleanup of cpuflag handling

   - kvm_stat counter improvements

   - VSIE improvements

   - mm cleanup

  x86:

   - hypervisor part of SEV

   - UMIP, RDPID, and MSR_SMI_COUNT emulation

   - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit

   - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more
     AVX512 features

   - show vcpu id in its anonymous inode name

   - many fixes and cleanups

   - per-VCPU MSR bitmaps (already merged through x86/pti branch)

   - stable KVM clock when nesting on Hyper-V (merged through
     x86/hyperv)"

* tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits)
  KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
  KVM: PPC: Book3S HV: Branch inside feature section
  KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
  KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code
  KVM: PPC: Book3S PR: Fix broken select due to misspelling
  KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs()
  KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled
  KVM: PPC: Book3S HV: Drop locks before reading guest memory
  kvm: x86: remove efer_reload entry in kvm_vcpu_stat
  KVM: x86: AMD Processor Topology Information
  x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested
  kvm: embed vcpu id to dentry of vcpu anon inode
  kvm: Map PFN-type memory regions as writable (if possible)
  x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n
  KVM: arm/arm64: Fixup userspace irqchip static key optimization
  KVM: arm/arm64: Fix userspace_irqchip_in_use counting
  KVM: arm/arm64: Fix incorrect timer_is_pending logic
  MAINTAINERS: update KVM/s390 maintainers
  MAINTAINERS: add Halil as additional vfio-ccw maintainer
  MAINTAINERS: add David as a reviewer for KVM/s390
  ...

59f47eff ("powerpc/pci: Use of_irq_parse_and_map_pci() helper")
replaced of_irq_parse_pci() + irq_create_of_mapping() with
of_irq_parse_and_map_pci(), but neglected to capture the virq
returned by irq_create_of_mapping(), so virq remained zero, which
caused INTx configuration to fail.

Save the virq value returned by of_irq_parse_and_map_pci() and correct
the virq declaration to match the of_irq_parse_and_map_pci() signature.

Fixes: 59f47eff "powerpc/pci: Use of_irq_parse_and_map_pci() helper"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Pull more Kbuild updates from Masahiro Yamada:
 "Makefile changes:
   - enable unused-variable warning that was wrongly disabled for clang

  Kconfig changes:
   - warn about blank 'help' and fix existing instances
   - fix 'choice' behavior to not write out invisible symbols
   - fix misc weirdness

  Coccinell changes:
   - fix false positive of free after managed memory alloc detection
   - improve performance of NULL dereference detection"

* tag 'kbuild-v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
  kconfig: remove const qualifier from sym_expand_string_value()
  kconfig: add xrealloc() helper
  kconfig: send error messages to stderr
  kconfig: echo stdin to stdout if either is redirected
  kconfig: remove check_stdin()
  kconfig: remove 'config*' pattern from .gitignnore
  kconfig: show '?' prompt even if no help text is available
  kconfig: do not write choice values when their dependency becomes n
  coccinelle: deref_null: avoid useless computation
  coccinelle: devm_free: reduce false positives
  kbuild: clang: disable unused variable warnings only when constant
  kconfig: Warn if help text is blank
  nios2: kconfig: Remove blank help text
  arm: vt8500: kconfig: Remove blank help text
  MIPS: kconfig: Remove blank help text
  MIPS: BCM63XX: kconfig: Remove blank help text
  lib/Kconfig.debug: Remove blank help text
  Staging: rtl8192e: kconfig: Remove blank help text
  Staging: rtl8192u: kconfig: Remove blank help text
  mmc: kconfig: Remove blank help text
  ...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull misc vfs fixes from Al Viro.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  seq_file: fix incomplete reset on read from zero offset
  kernfs: fix regression in kernfs_fop_write caused by wrong type

This function returns realloc'ed memory, so the returned pointer
must be passed to free() when done.  So, 'const' qualifier is odd.
It is allowed to modify the expanded string.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

We already have xmalloc(), xcalloc().  Add xrealloc() as well
to save tedious error handling.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

It adds support for new Mellanox system types of basic classes qmb7, sn34,
sn37, containing systems QMB700 (40x200GbE InfiniBand switch), SN3700
(32x200GbE and 16x400GbE Ethernet switch) and SN3410 (6x400GbE plus
48x50GbE Ethernet switch). These are the Top of the Rack systems, equipped
with Mellanox COM-Express carrier board and switch board with Mellanox
Quantum device, which supports InfiniBand switching with 40X200G ports and
line rate of up to HDR speed or with Mellanox Spectrum-2 device, which
supports Ethernet switching with 32X200G ports line rate of up to HDR
speed.
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

It adds support for new Mellanox system types of basic half unit size
class msn201x, containing system MSN2010 (18x10GbE plus 4x4x25GbE) half
and its derivatives. This is the Top of the Rack system, equipped with
Mellanox Small Form Factor carrier board and switch board with Mellanox
Spectrum device, which supports Ethernet switching with 32X100G ports line
rate of up to EDR speed.
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

It adds support for new Mellanox system types of basic class msn274x,
containing system MSN2740 (32x100GbE Ethernet switch with cost reduction)
and its derivatives. These are the Top of the Rack system, equipped with
Mellanox Small Form Factor carrier board and switch board with Mellanox
Spectrum device, which supports Ethernet switching with 32X100G ports line
rate of up to EDR speed.
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

Pull networking fixes from David Miller:

 1) Make allocations less aggressive in x_tables, from Minchal Hocko.

 2) Fix netfilter flowtable Kconfig deps, from Pablo Neira Ayuso.

 3) Fix connection loss problems in rtlwifi, from Larry Finger.

 4) Correct DRAM dump length for some chips in ath10k driver, from Yu
    Wang.

 5) Fix ABORT handling in rxrpc, from David Howells.

 6) Add SPDX tags to Sun networking drivers, from Shannon Nelson.

 7) Some ipv6 onlink handling fixes, from David Ahern.

 8) Netem packet scheduler interval calcualtion fix from Md. Islam.

 9) Don't put crypto buffers on-stack in rxrpc, from David Howells.

10) Fix handling of error non-delivery status in netlink multicast
    delivery over multiple namespaces, from Nicolas Dichtel.

11) Missing xdp flush in tuntap driver, from Jason Wang.

12) Synchonize RDS protocol netns/module teardown with rds object
    management, from Sowini Varadhan.

13) Add nospec annotations to mpls, from Dan Williams.

14) Fix SKB truesize handling in TIPC, from Hoang Le.

15) Interrupt masking fixes in stammc from Niklas Cassel.

16) Don't allow ptr_ring objects to be sized outside of kmalloc's
    limits, from Jason Wang.

17) Don't allow SCTP chunks to be built which will have a length
    exceeding the chunk header's 16-bit length field, from Alexey
    Kodanev.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (82 commits)
  ibmvnic: Remove skb->protocol checks in ibmvnic_xmit
  bpf: fix rlimit in reuseport net selftest
  sctp: verify size of a new chunk in _sctp_make_chunk()
  s390/qeth: fix SETIP command handling
  s390/qeth: fix underestimated count of buffer elements
  ptr_ring: try vmalloc() when kmalloc() fails
  ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE
  net: stmmac: remove redundant enable of PMT irq
  net: stmmac: rename GMAC_INT_DEFAULT_MASK for dwmac4
  net: stmmac: discard disabled flags in interrupt status register
  ibmvnic: Reset long term map ID counter
  tools/libbpf: handle issues with bpf ELF objects containing .eh_frames
  selftests/bpf: add selftest that use test_libbpf_open
  selftests/bpf: add test program for loading BPF ELF files
  tools/libbpf: improve the pr_debug statements to contain section numbers
  bpf: Sync kernel ABI header with tooling header for bpf_common.h
  net: phy: fix phy_start to consider PHY_IGNORE_INTERRUPT
  net: thunder: change q_len's type to handle max ring size
  tipc: fix skb truesize/datasize ratio control
  net/sched: cls_u32: fix cls_u32 on filter replace
  ...

Pull more NFS client updates from Trond Myklebust:
 "A few bugfixes and some small sunrpc latency/performance improvements
  before the merge window closes:

  Stable fixes:

   - fix an incorrect calculation of the RDMA send scatter gather
     element limit

   - fix an Oops when attempting to free resources after RDMA device
     removal

  Bugfixes:

   - SUNRPC: Ensure we always release the TCP socket in a timely fashion
     when the connection is shut down.

   - SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context

  Latency/Performance:

   - SUNRPC: Queue latency sensitive socket tasks to the less contended
     xprtiod queue

   - SUNRPC: Make the xprtiod workqueue unbounded.

   - SUNRPC: Make the rpciod workqueue unbounded"

* tag 'nfs-for-4.16-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context
  fix parallelism for rpc tasks
  Make the xprtiod workqueue unbounded.
  SUNRPC: Queue latency-sensitive socket tasks to xprtiod
  SUNRPC: Ensure we always close the socket after a connection shuts down
  xprtrdma: Fix BUG after a device removal
  xprtrdma: Fix calculation of ri_max_send_sges

Pull SCSI target updates from Nicholas Bellinger:
 "The highlights include:

   - numerous target-core-user improvements related to queue full and
     timeout handling. (MNC)

   - prevent target-core-user corruption when invalid data page is
     requested. (MNC)

   - add target-core device action configfs attributes to allow
     user-space to trigger events separate from existing attributes
     exposed to end-users. (MNC)

   - fix iscsi-target NULL pointer dereference 4.6+ regression in CHAP
     error path. (David Disseldorp)

   - avoid target-core backend UNMAP callbacks if range is zero. (Andrei
     Vagin)

   - fix a iscsi-target 4.14+ regression related multiple PDU logins,
     that was exposed due to removal of TCP prequeue support. (Florian
     Westphal + MNC)

  Also, there is a iser-target bug still being worked on for post -rc1
  code to address a long standing issue resulting in persistent
  ib_post_send() failures, for RNICs with small max_send_sge"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (36 commits)
  iscsi-target: make sure to wake up sleeping login worker
  tcmu: Fix trailing semicolon
  tcmu: fix cmd user after free
  target: fix destroy device in target_configure_device
  tcmu: allow userspace to reset ring
  target core: add device action configfs files
  tcmu: fix error return code in tcmu_configure_device()
  target_core_user: add cmd id to broken ring message
  target: add SAM_STAT_BUSY sense reason
  tcmu: prevent corruption when invalid data page requested
  target: don't call an unmap callback if a range length is zero
  target/iscsi: avoid NULL dereference in CHAP auth error path
  cxgbit: call neigh_event_send() to update MAC address
  target: tcm_loop: Use seq_puts() in tcm_loop_show_info()
  target: tcm_loop: Delete an unnecessary return statement in tcm_loop_submission_work()
  target: tcm_loop: Delete two unnecessary variable initialisations in tcm_loop_issue_tmr()
  target: tcm_loop: Combine substrings for 26 messages
  target: tcm_loop: Improve a size determination in two functions
  target: tcm_loop: Delete an error message for a failed memory allocation in four functions
  sbp-target: Delete an error message for a failed memory allocation in three functions
  ...

Pull tracing fixes from Steven Rostedt:
 "Al Viro discovered some breakage with the parsing of the
  set_ftrace_filter as well as the removing of function probes.

  This fixes the code with Al's suggestions. I also added a few
  selftests to test the broken cases such that they wont happen
  again"

* tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Add more tests for removing of function probes
  selftests/ftrace: Add some missing glob checks
  selftests/ftrace: Have reset_ftrace_filter handle multiple instances
  selftests/ftrace: Have reset_ftrace_filter handle modules
  tracing: Fix parsing of globs with a wildcard at the beginning
  ftrace: Remove incorrect setting of glob search field

Pull cifs fixes from Steve French:
 "There are a couple additional security fixes that are still being
  tested that are not in this set."

* tag '4.16-minor-rc-SMB3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  Add missing structs and defines from recent SMB3.1.1 documentation
  address lock imbalance warnings in smbdirect.c
  cifs: silence compiler warnings showing up with gcc-8.0.0
  Add some missing debug fields in server and tcon structs

Pull fbdev fix from Bartlomiej Zolnierkiewicz:
 "Fix building of the omapfb driver (Tomi Valkeinen)"

* tag 'fbdev-v4.16-fix' of git://github.com/bzolnier/linux:
  video: omapfb: fix missing #includes

Second PPC KVM update for 4.16

Seven fixes that are either trivial or that address bugs that people
are actually hitting.  The main ones are:

- Drop spinlocks before reading guest memory

- Fix a bug causing corruption of VCPU state in PR KVM with preemption
  enabled

- Make HPT resizing work on POWER9

- Add MMIO emulation for vector loads and stores, because guests now
  use these instructions in memcpy and similar routines.