32-bit code has PER_CPU_VAR(cpu_current_top_of_stack).
64-bit code uses somewhat more obscure: PER_CPU_VAR(cpu_tss + TSS_sp0).

Define the 'cpu_current_top_of_stack' macro on CONFIG_X86_64
as well so that the PER_CPU_VAR(cpu_current_top_of_stack)
expression can be used in both 32-bit and 64-bit code.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-3-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-2-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

PER_CPU_VAR(kernel_stack) is redundant:

  - On the 64-bit build, we can use PER_CPU_VAR(cpu_tss + TSS_sp0).
  - On the 32-bit build, we can use PER_CPU_VAR(cpu_current_top_of_stack).

PER_CPU_VAR(kernel_stack) will be deleted by a separate change.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-1-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

On AMD CPUs, SYSRET can return with a valid SS descriptor with
with the hidden attributes set to an unusable state.  Make sure
the kernel doesn't let this happen.  This detects an
as-yet-unfixed regression.

Note that the 64-bit version of this test fails on AMD CPUs on
all kernel versions, although the issue in the 64-bit case is
much less severe than in the 32-bit case.
Reported-by: Brian Gerst <brgerst@gmail.com>
Tested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Tests: e7d6eefa ("x86/vdso32/syscall.S: Do not load __USER32_DS to %ss")
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/resend_4d740841bac383742949e2fefb03982736595087.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously
doesn't inline very small functions we expect to be inlined:

$ nm --size-sort vmlinux | grep -iF ' t ' | uniq -c | grep -v '^
*1 ' | sort -rn     473 000000000000000b t spin_unlock_irqrestore
    449 000000000000005f t rcu_read_unlock
    355 0000000000000009 t atomic_inc                <== THIS
    353 000000000000006e t rcu_read_lock
    350 0000000000000075 t rcu_read_lock_sched_held
    291 000000000000000b t spin_unlock
    266 0000000000000019 t arch_local_irq_restore
    215 000000000000000b t spin_lock
    180 0000000000000011 t kzalloc
    165 0000000000000012 t list_add_tail
    161 0000000000000019 t arch_local_save_flags
    153 0000000000000016 t test_and_set_bit
    134 000000000000000b t spin_unlock_irq
    134 0000000000000009 t atomic_dec                <== THIS
    130 000000000000000b t spin_unlock_bh
    122 0000000000000010 t brelse
    120 0000000000000016 t test_and_clear_bit
    120 000000000000000b t spin_lock_irq
    119 000000000000001e t get_dma_ops
    117 0000000000000053 t cpumask_next
    116 0000000000000036 t kref_get
    114 000000000000001a t schedule_work
    106 000000000000000b t spin_lock_bh
    103 0000000000000019 t arch_local_irq_disable
...

Note sizes of marked functions. They are merely 9 bytes long!
Selecting function with 'atomic' in their names:

    355 0000000000000009 t atomic_inc
    134 0000000000000009 t atomic_dec
     98 0000000000000014 t atomic_dec_and_test
     31 000000000000000e t atomic_add_return
     27 000000000000000a t atomic64_inc
     26 000000000000002f t kmap_atomic
     24 0000000000000009 t atomic_add
     12 0000000000000009 t atomic_sub
     10 0000000000000021 t __atomic_add_unless
     10 000000000000000a t atomic64_add
      5 000000000000001f t __atomic_add_unless.constprop.7
      5 000000000000000a t atomic64_dec
      4 000000000000001f t __atomic_add_unless.constprop.18
      4 000000000000001f t __atomic_add_unless.constprop.12
      4 000000000000001f t __atomic_add_unless.constprop.10
      3 000000000000001f t __atomic_add_unless.constprop.13
      3 0000000000000011 t atomic64_add_return
      2 000000000000001f t __atomic_add_unless.constprop.9
      2 000000000000001f t __atomic_add_unless.constprop.8
      2 000000000000001f t __atomic_add_unless.constprop.6
      2 000000000000001f t __atomic_add_unless.constprop.5
      2 000000000000001f t __atomic_add_unless.constprop.3
      2 000000000000001f t __atomic_add_unless.constprop.22
      2 000000000000001f t __atomic_add_unless.constprop.14
      2 000000000000001f t __atomic_add_unless.constprop.11
      2 000000000000001e t atomic_dec_if_positive
      2 0000000000000014 t atomic_inc_and_test
      2 0000000000000011 t atomic_add_return.constprop.4
      2 0000000000000011 t atomic_add_return.constprop.17
      2 0000000000000011 t atomic_add_return.constprop.16
      2 000000000000000d t atomic_inc.constprop.4
      2 000000000000000c t atomic_cmpxchg

This patch fixes this for x86 atomic ops via
s/inline/__always_inline/. This decreases allyesconfig kernel by
about 25k:

    text     data      bss       dec     hex filename
82399481 22255416 20627456 125282353 777a831 vmlinux.before
82375570 22255544 20627456 125258570 7774b4a vmlinux
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1431080762-17797-1-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

By the nature of TEST operation, it is often possible
to test a narrower part of the operand:

    "testl $3, mem"  -> "testb $3, mem"

This results in shorter insns, because TEST insn has no
sign-entending byte-immediate forms unlike other ALU ops.

   text	   data	    bss	    dec	    hex	filename
  11674	      0	      0	  11674	   2d9a	entry_64.o.before
  11658	      0	      0	  11658	   2d8a	entry_64.o

Changes in object code:

-	f7 84 24 88 00 00 00 03 00 00 00 	testl  $0x3,0x88(%rsp)
+	f6 84 24 88 00 00 00 03	         	testb  $0x3,0x88(%rsp)
-	f7 44 24 68 03 00 00 00          	testl  $0x3,0x68(%rsp)
+	f6 44 24 68 03                  	testb  $0x3,0x68(%rsp)
-	f7 84 24 90 00 00 00 03 00 00 00	testl  $0x3,0x90(%rsp)
+	f6 84 24 90 00 00 00 03         	testb  $0x3,0x90(%rsp)
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1430140912-7960-2-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

After TESTs, use logically correct JZ/JNZ mnemonics instead of
JE/JNE. This doesn't change code.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1430140912-7960-1-git-send-email-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull power management and ACPI fixes from Rafael Wysocki:
 "These include three regression fixes (PCI resources management,
  ACPI/PNP device enumeration, ACPI SBS on MacBook) and two ACPI
  documentation fixes related to GPIO.

  Specifics:

   - Fix for a PCI resources management regression introduced during the
     4.0 cycle and related to the handling of ACPI resources'
     Producer/Consumer flags that turn out to be useless (Jiang Liu)

   - Fix for a MacBook regression related to the Smart Battery Subsystem
     (SBS) driver causing various problems (stalls on boot, failure to
     detect or report battery) to happen and introduced during the 3.18
     cycle (Chris Bainbridge)

   - Fix for an ACPI/PNP device enumeration regression introduced during
     the 3.16 cycle caused by failing to include two PNP device IDs into
     the list of IDs that PNP device objects need to be created for
     (Witold Szczeponik)

   - Fixes for two minor mistakes in the ACPI GPIO properties
     documentation (Antonio Ospite, Rafael J Wysocki)"

* tag 'pm+acpi-4.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PNP: add two IDs to list for PNPACPI device enumeration
  ACPI / documentation: Fix ambiguity in the GPIO properties document
  ACPI / documentation: fix a sentence about GPIO resources
  ACPI / SBS: Add 5 us delay to fix SBS hangs on MacBook
  x86/PCI/ACPI: Make all resources except [io 0xcf8-0xcff] available on PCI bus

* acpi-resources:
  x86/PCI/ACPI: Make all resources except [io 0xcf8-0xcff] available on PCI bus

* acpi-battery:
  ACPI / SBS: Add 5 us delay to fix SBS hangs on MacBook

* acpi-doc:
  ACPI / documentation: Fix ambiguity in the GPIO properties document
  ACPI / documentation: fix a sentence about GPIO resources

* acpi-pnp:
  ACPI / PNP: add two IDs to list for PNPACPI device enumeration

Pull f2fs fixes from Jaegeuk Kim:
 "Fix a performance regression and a bug"

* tag 'for-f2fs-4.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: fix wrong error hanlder in f2fs_follow_link
  Revert "f2fs: enhance multi-threads performance"

Pull pin control fixes from Linus Walleij:
 "Here is a smallish set of pin control fixes for the v4.1 cycle,
  collected the last two weeks:

   - fix a real nasty legacy bug that has screwed up the protection of
     adding pinctrl maps dynamically.  Normally this didn't happen so
     much but Dough Anderson ran into it and fixed it, kudos!

  - minor driver fixes for Qualcomm spmi, mediatek and Marvell drivers"

* tag 'pinctrl-v4.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: Don't just pretend to protect pinctrl_maps, do it for real
  pinctrl: mediatek: mtk-common: initialize unmask
  pinctrl: qcom-spmi-mpp: Fix input value report
  pinctrl: qcom-spmi: Fix pin direction configuration
  pinctrl: mvebu: Fix mapping of pin 63 (gpo -> gpio)

Pull vfio fixes from Alex Williamson:
 "Fix some undesirable behavior with the vfio device request interface:

   - increase verbosity of device request channel (Alex Williamson)

   - fix runaway interruptible timeout (Alex Williamson)"

* tag 'vfio-v4.1-rc3' of git://github.com/awilliam/linux-vfio:
  vfio: Fix runaway interruptible timeout
  vfio-pci: Log device requests more verbosely

Pull infiniband updates from Doug Ledford:
 "Minor updates for 4.1-rc

  Most of the changes are fairly small and well confined.  The iWARP
  address reporting changes are the only ones that are a medium size.  I
  had these queued up prior to rc1, but due to the shuffle in
  maintainers, they did not get submitted when I expected.  My apologies
  for that.  I feel comfortable with them however due to the testing
  they've received, so I left them in this submission"

* tag 'for-linus' of git://github.com/dledford/linux:
  MAINTAINERS: Update InfiniBand subsystem maintainer
  MAINTAINERS: add include/rdma/ to InfiniBand subsystem
  IPoIB/CM: Fix indentation level
  iw_cxgb4: Remove negative advice dmesg warnings
  IB/core: Fix unaligned accesses
  IB/core: change rdma_gid2ip into void function as it always return zero
  IB/qib: use arch_phys_wc_add()
  IB/qib: add acounting for MTRR
  IB/core: dma unmap optimizations
  IB/core: dma map/unmap locking optimizations
  RDMA/cxgb4: Report the actual address of the remote connecting peer
  RDMA/nes: Report the actual address of the remote connecting peer
  RDMA/core: Enable the iWarp Port Mapper to provide the actual address of the connecting peer to its clients
  iw_cxgb4: enforce qp/cq id requirements
  iw_cxgb4: use BAR2 GTS register for T5 kernel mode CQs
  iw_cxgb4: 32b platform fixes
  iw_cxgb4: Cleanup register defines/MACROS
  RDMA/CMA: Canonize IPv4 on IPV6 sockets properly

Pull xen bug fixes from David Vrabel:

 - fix blkback regression if using persistent grants

 - fix various event channel related suspend/resume bugs

 - fix AMD x86 regression with X86_BUG_SYSRET_SS_ATTRS

 - SWIOTLB on ARM now uses frames <4 GiB (if available) so device only
   capable of 32-bit DMA work.

* tag 'for-linus-4.1b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARM
  hypervisor/x86/xen: Unset X86_BUG_SYSRET_SS_ATTRS on Xen PV guests
  xen/events: Set irq_info->evtchn before binding the channel to CPU in __startup_pirq()
  xen/console: Update console event channel on resume
  xen/xenbus: Update xenbus event channel on resume
  xen/events: Clear cpu_evtchn_mask before resuming
  xen-pciback: Add name prefix to global 'permissive' variable
  xen: Suspend ticks on all CPUs during suspend
  xen/grant: introduce func gnttab_unmap_refs_sync()
  xen/blkback: safely unmap purge persistent grants

Pull x86 fixes from Ingo Molnar:
 "EFI fixes, and FPU fix, a ticket spinlock boundary condition fix and
  two build fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Always restore_xinit_state() when use_eager_cpu()
  x86: Make cpu_tss available to external modules
  efi: Fix error handling in add_sysfs_runtime_map_entry()
  x86/spinlocks: Fix regression in spinlock contention detection
  x86/mm: Clean up types in xlate_dev_mem_ptr()
  x86/efi: Store upper bits of command line buffer address in ext_cmd_line_ptr
  efivarfs: Ensure VariableName is NUL-terminated

Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also an uncore PMU driver fix and an uncore
  PMU driver hardware-enablement addition"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf probe: Fix segfault if passed with ''.
  perf report: Fix -T/--threads option to work again
  perf bench numa: Fix immediate meeting of convergence condition
  perf bench numa: Fixes of --quiet argument
  perf bench futex: Fix hung wakeup tasks after requeueing
  perf probe: Fix bug with global variables handling
  perf top: Fix a segfault when kernel map is restricted.
  tools lib traceevent: Fix build failure on 32-bit arch
  perf kmem: Fix compiles on RHEL6/OL6
  tools lib api: Undefine _FORTIFY_SOURCE before setting it
  perf kmem: Consistently use PRIu64 for printing u64 values
  perf trace: Disable events and drain events when forked workload ends
  perf trace: Enable events when doing system wide tracing and starting a workload
  perf/x86/intel/uncore: Move PCI IDs for IMC to uncore driver
  perf/x86/intel/uncore: Add support for Intel Haswell ULT (lower power Mobile Processor) IMC uncore PMUs
  perf/x86/intel: Add cpu_(prepare|starting|dying) for core_pmu

Pull RCU fix from Ingo Molnar:
 "An RCU Kconfig fix that eliminates an annoying interactive kconfig
  question for CONFIG_RCU_TORTURE_TEST_SLOW_INIT"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Control grace-period delays directly from value

Way back, when the world was a simpler place and there was no war, no
evil, and no kernel bugs, there was just a single pinctrl lock.  That
was how the world was when (57291ce2 pinctrl: core device tree mapping
table parsing support) was written.  In that case, there were
instances where the pinctrl mutex was already held when
pinctrl_register_map() was called, hence a "locked" parameter was
passed to the function to indicate that the mutex was already locked
(so we shouldn't lock it again).

A few years ago in (42fed7ba pinctrl: move subsystem mutex to
pinctrl_dev struct), we switched to a separate pinctrl_maps_mutex.
...but (oops) we forgot to re-think about the whole "locked" parameter
for pinctrl_register_map().  Basically the "locked" parameter appears
to still refer to whether the bigger pinctrl_dev mutex is locked, but
we're using it to skip locks of our (now separate) pinctrl_maps_mutex.

That's kind of a bad thing(TM).  Probably nobody noticed because most
of the calls to pinctrl_register_map happen at boot time and we've got
synchronous device probing.  ...and even cases where we're
asynchronous don't end up actually hitting the race too often.  ...but
after banging my head against the wall for a bug that reproduced 1 out
of 1000 reboots and lots of looking through kgdb, I finally noticed
this.

Anyway, we can now safely remove the "locked" parameter and go back to
a war-free, evil-free, and kernel-bug-free world.

Fixes: 42fed7ba ("pinctrl: move subsystem mutex to pinctrl_dev struct")
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Make sure that xen_swiotlb_init allocates buffers that are DMA capable
when at least one memblock is available below 4G. Otherwise we assume
that all devices on the SoC can cope with >4G addresses. We do this on
ARM and ARM64, where dom0 is mapped 1:1, so pfn == mfn in this case.

No functional changes on x86.

From: Chen Baozi <baozich@gmail.com>
Signed-off-by: Chen Baozi <baozich@gmail.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Chen Baozi <baozich@gmail.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

Add some text to the macro magic for future reference and against
failing human memory.
Requested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

The following commit:

  f893959b ("x86/fpu: Don't abuse drop_init_fpu() in flush_thread()")

removed drop_init_fpu() usage from flush_thread(). This seems to break
things for me - the Go 1.4 test suite fails all over the place with
floating point comparision errors (offending commit found through
bisection).

The functional change was that flush_thread() after this commit
only calls restore_init_xstate() when both use_eager_fpu() and
!used_math() are true. drop_init_fpu() (now fpu_reset_state()) calls
restore_init_xstate() regardless of whether current used_math() - apply
the same logic here.

Switch used_math() -> tsk_used_math(tsk) to consistently use the grabbed
tsk instead of current, like in the rest of flush_thread().
Tested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pekka Riikonen <priikone@iki.fi>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: f893959b ("x86/fpu: Don't abuse drop_init_fpu() in flush_thread()")
Link: http://lkml.kernel.org/r/1430147441-9820-1-git-send-email-bobbypowers@gmail.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

GCC 5 added a compiler option, -mskip-rax-setup, for x86-64. It skips
setting up the RAX register when SSE is disabled and there are no
variable arguments passed in vector registers. (According to the x86_64
ABI, %al is used as a hidden register containing the number of vector
registers used).

Since the kernel doesn't pass vector registers to functions with
variable arguments, this option can be used to optimize the x86-64
kernel.

This GCC feature was suggested by Rasmus Villemoes <linux@rasmusvillemoes.dk>.
This is the corresponding kernel change using it.

For kernel v3.17:

      text   data    bss    dec       filename
  11455921 2204048 5853184 19513153   vmlinux #with -mskip-rax-setup
  11480079 2204048 5853184 19537311   vmlinux

For Kernel v4.0+ - custom config:

      text   data    bss    dec       filename
  10231778 3479800 16617472 30329050  vmlinux-gcc5+-mskip-rax-setup
  10268797 3547448 16621568 30437813  vmlinux
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

 * Avoid garbage names in efivarfs due to buggy firmware by zeroing
   EFI variable name. (Ross Lagerwall)

 * Stop erroneously dropping upper 32 bits of boot command line pointer
   in EFI boot stub and stash them in ext_cmd_line_ptr. (Roy Franz)

 * Fix double-free bug in error handling code path of EFI runtime map
   code. (Dan Carpenter)
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

  - Fix 'perf probe -a' segfault if passed with '' (Wang Nan)

  - Fix report -T/--threads option (Namhyung Kim)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull IPMI fixes from Corey Minyard:
 "Lots of minor IPMI fixes, especially ones that have have come up since
  the SSIF driver has been in the main kernel for a while"

* tag 'for-linus-4.1-1' of git://git.code.sf.net/p/openipmi/linux-ipmi:
  ipmi: Fix multi-part message handling
  ipmi: Add alert handling to SSIF
  ipmi: Fix a problem that messages are not issued in run_to_completion mode
  ipmi: Report an error if ACPI _IFT doesn't exist
  ipmi: Remove unused including <linux/version.h>
  ipmi: Don't report err in the SI driver for SSIF devices
  ipmi: Remove incorrect use of seq_has_overflowed
  ipmi:ssif: Ignore spaces when comparing I2C adapter names
  ipmi_ssif: Fix the logic on user-supplied addresses

Merge misc fixes from Andrew Morton:
 "16 patches

  This includes a new rtc driver for the Abracon AB x80x and isn't very
  appropriate for -rc2.  It was still being fiddled with a bit during
  the merge window and I fell asleep during -rc1"

[ So I took the new driver, it seems small and won't regress anything.
  I'm a softy.   - Linus ]

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  rtc: armada38x: fix concurrency access in armada38x_rtc_set_time
  ocfs2: dlm: fix race between purge and get lock resource
  nilfs2: fix sanity check of btree level in nilfs_btree_root_broken()
  util_macros.h: have array pointer point to array of constants
  configfs: init configfs module earlier at boot time
  mm/hwpoison-inject: check PageLRU of hpage
  mm/hwpoison-inject: fix refcounting in no-injection case
  mm: soft-offline: fix num_poisoned_pages counting on concurrent events
  rtc: add rtc-abx80x, a driver for the Abracon AB x80x i2c rtc
  Documentation: bindings: add abracon,abx80x
  kasan: show gcc version requirements in Kconfig and Documentation
  mm/memory-failure: call shake_page() when error hits thp tail page
  lib: delete lib/find_last_bit.c
  MAINTAINERS: add co-maintainer for LED subsystem
  zram: add Designated Reviewer for zram in MAINTAINERS
  revert "zram: move compact_store() to sysfs functions area"

Merge tag 'platform-drivers-x86-v4.1-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull x86 platform driver fixes from Darren Hart:
 "This includes a trivial warning and adding a Lenovo laptop to an
  existing quirk.

  I've held off on things like the latter in the past, but I didn't feel
  it was risky enough to push out to 4.2.

   - thinkpad_acpi:
        Fix warning for static not at beginning

   - ideapad_laptop:
        Add Lenovo G40-30 to devices without radio switch"

* tag 'platform-drivers-x86-v4.1-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
  thinkpad_acpi: Fix warning for static not at beginning
  ideapad_laptop: Add Lenovo G40-30 to devices without radio switch

Lots of little fixes for multi-part messages:

The values was not being re-initialized, if something went wrong
handling a multi-part message and it got left in a bad state, it
might be an issue.

The commands were not correct when issuing multi-part reads, the
code was not passing in the proper value for commands.  Also clean
up some minor formatting issues.

Get the block number from the right location, limit the maximum send
message size to 63 bytes and explain why, and fix some minor sylistic
issues.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

The SSIF interface can optionally have an SMBus alert come in when
data is ready.  Unfortunately, the IPMI spec gives wiggle room to
the implementer to allow them to always have the alert enabled,
even if the driver doesn't enable it.  So implement alerts.
If you don't in this situation, the SMBus alert handling will
constantly complain.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

start_next_msg() issues a message placed in smi_info->waiting_msg
if it is non-NULL.  However, sender() sets a message to
smi_info->curr_msg and NULL to smi_info->waiting_msg in the context
of run_to_completion mode.  As the result, it leads an infinite
loop by waiting the completion of unissued message when leaving
dying message after kernel panic.

sender() should set the message to smi_info->waiting_msg not
curr_msg.
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>

When probing an ACPI table, report a specific error, instead of just
returning an error, if _IFT doesn't exist.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

Remove including <linux/version.h> that don't need it.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Corey Minyard <cminyard@mvista.com>

While setting the time, the RTC TIME register should not be accessed.
However due to hardware constraints, setting the RTC time involves
sleeping during 100ms.  This sleep was done outside the critical section
protected by the spinlock, so it was possible to read the RTC TIME
register and get an incorrect value.  This patch introduces a mutex for
protecting the RTC TIME access, unlike the spinlock it is allowed to
sleep in a critical section protected by a mutex.

The RTC STATUS register can still be used from the interrupt handler but
it has no effect on setting the time.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>	[4.0]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There is a race window in dlm_get_lock_resource(), which may return a
lock resource which has been purged.  This will cause the process to
hang forever in dlmlock() as the ast msg can't be handled due to its
lock resource not existing.

    dlm_get_lock_resource {
        ...
        spin_lock(&dlm->spinlock);
        tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash);
        if (tmpres) {
             spin_unlock(&dlm->spinlock);
             >>>>>>>> race window, dlm_run_purge_list() may run and purge
                              the lock resource
             spin_lock(&tmpres->spinlock);
             ...
             spin_unlock(&tmpres->spinlock);
        }
    }
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The range check for b-tree level parameter in nilfs_btree_root_broken()
is wrong; it accepts the case of "level == NILFS_BTREE_LEVEL_MAX" even
though the level is limited to values in the range of 0 to
(NILFS_BTREE_LEVEL_MAX - 1).

Since the level parameter is read from storage device and used to index
nilfs_btree_path array whose element count is NILFS_BTREE_LEVEL_MAX, it
can cause memory overrun during btree operations if the boundary value
is set to the level parameter on device.

This fixes the broken sanity check and adds a comment to clarify that
the upper bound NILFS_BTREE_LEVEL_MAX is exclusive.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Using the new find_closest() macro can result in the following sparse
warnings.

  drivers/hwmon/lm85.c:194:16: warning:
  		incorrect type in initializer (different modifiers)
  drivers/hwmon/lm85.c:194:16:    expected int *__fc_a
  drivers/hwmon/lm85.c:194:16:    got int static const [toplevel] *<noident>
  drivers/hwmon/lm85.c:210:16: warning:
  		incorrect type in initializer (different modifiers)
  drivers/hwmon/lm85.c:210:16:    expected int *__fc_a
  drivers/hwmon/lm85.c:210:16:    got int const *map

This is because the array passed to find_closest() will typically be
declared as array of constants, but the macro declares a non-constant
pointer to it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We need this earlier in the boot process to allow various subsystems to
use configfs (e.g Industrial IIO).

Also, debugfs is at core_initcall level and configfs should be on the same
level from infrastructure point of view.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Suggested-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Hwpoison injector checks PageLRU of the raw target page to find out
whether the page is an appropriate target, but current code now filters
out thp tail pages, which prevents us from testing for such cases via this
interface.  So let's check hpage instead of p.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Dean Nelson <dnelson@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Hwpoison injection via debugfs:hwpoison/corrupt-pfn takes a refcount of
the target page.  But current code doesn't release it if the target page
is not supposed to be injected, which results in memory leak.  This patch
simply adds the refcount releasing code.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Dean Nelson <dnelson@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>