The AES loops in arch/sparc/crypto/aes_glue.c use a scheme where the
key material is preloaded into the FPU registers, and then we loop
over and over doing the crypt operation, reusing those pre-cooked key
registers.

There are intervening blkcipher*() calls between the crypt operation
calls.  And those might perform memcpy() and thus also try to use the
FPU.

The sparc64 kernel FPU usage mechanism is designed to allow such
recursive uses, but with a catch.

There has to be a trap between the two FPU using threads of control.

The mechanism works by, when the FPU is already in use by the kernel,
allocating a slot for FPU saving at trap time.  Then if, within the
trap handler, we try to use the FPU registers, the pre-trap FPU
register state is saved into the slot.  Then at trap return time we
notice this and restore the pre-trap FPU state.

Over the long term there are various more involved ways we can make
this work, but for a quick fix let's take advantage of the fact that
the situation where this happens is very limited.

All sparc64 chips that support the crypto instructiosn also are using
the Niagara4 memcpy routine, and that routine only uses the FPU for
large copies where we can't get the source aligned properly to a
multiple of 8 bytes.

We look to see if the FPU is already in use in this context, and if so
we use the non-large copy path which only uses integer registers.

Furthermore, we also limit this special logic to when we are doing
kernel copy, rather than a user copy.
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull drm updates from Dave Airlie:
 "This is the main git pull for the drm,

  I pretty much froze major pulls at -rc5/6 time, and haven't had much
  fallout, so will probably continue doing that.

  Lots of changes all over, big internal header cleanup to make it clear
  drm features are legacy things and what are things that modern KMS
  drivers should be using.  Also big move to use the new generic fences
  in all the TTM drivers.

  core:
        atomic prep work,
        vblank rework changes, allows immediate vblank disables
        major header reworking and cleanups to better delinate legacy
        interfaces from what KMS drivers should be using.
        cursor planes locking fixes

  ttm:
        move to generic fences (affects all TTM drivers)
        ppc64 caching fixes

  radeon:
        userptr support,
        uvd for old asics,
        reset rework for fence changes
        better buffer placement changes,
        dpm feature enablement
        hdmi audio support fixes

  intel:
        Cherryview work,
        180 degree rotation,
        skylake prep work,
        execlist command submission
        full ppgtt prep work
        cursor improvements
        edid caching,
        vdd handling improvements

  nouveau:
        fence reworking
        kepler memory clock work
        gt21x clock work
        fan control improvements
        hdmi infoframe fixes
        DP audio

  ast:
        ppc64 fixes
        caching fix

  rcar:
        rcar-du DT support

  ipuv3:
        prep work for capture support

  msm:
        LVDS support for mdp4, new panel, gpu refactoring

  exynos:
        exynos3250 SoC support, drop bad mmap interface,
        mipi dsi changes, and component match support"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (640 commits)
  drm/mst: rework payload table allocation to conform better.
  drm/ast: Fix HW cursor image
  drm/radeon/kv: add uvd/vce info to dpm debugfs output
  drm/radeon/ci: add uvd/vce info to dpm debugfs output
  drm/radeon: export reservation_object from dmabuf to ttm
  drm/radeon: cope with foreign fences inside the reservation object
  drm/radeon: cope with foreign fences inside display
  drm/core: use helper to check driver features
  drm/radeon/cik: write gfx ucode version to ucode addr reg
  drm/radeon/si: print full CS when we hit a packet 0
  drm/radeon: remove unecessary includes
  drm/radeon/combios: declare legacy_connector_convert as static
  drm/radeon/atombios: declare connector convert tables as static
  drm/radeon: drop btc_get_max_clock_from_voltage_dependency_table
  drm/radeon/dpm: drop clk/voltage dependency filters for BTC
  drm/radeon/dpm: drop clk/voltage dependency filters for CI
  drm/radeon/dpm: drop clk/voltage dependency filters for SI
  drm/radeon/dpm: drop clk/voltage dependency filters for NI
  drm/radeon: disable audio when we disable hdmi (v2)
  drm/radeon: split audio enable between eg and r600 (v2)
  ...

Pull misc kbuild updates from Michal Marek:
 "This is the less critical kbuild stuff for v3.18-rc1:

   - make deb-pkg debuginfo fix, ppc64el support and warning fix for
     recent dpkg tools
   - make TAGS fixes
   - new coccinelle patch
   - kbuild documentation improvements"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  deb-pkg: remove obsolete -isp option to dpkg-gencontrol
  coccinelle: misc: semantic patch to delete overly complex return code processing
  deb-pkg: Add support for powerpc little endian
  builddeb: put the dbg files into the correct directory
  scripts/tags.sh: fix DEFINE_HASHTABLE in emacs case
  scripts/tags.sh: remove *PCGFLAGS regular expressions
  scripts/tags.sh: Don't specify kind-spec for emacs' ctags/etags
  Documentation: kbuild: Improve grammar
  Documentation: kbuild: Remove obsolete dtc_cpp section
  Documentation: kbuild: Improve if_changed documentation
  Documentation: kbuild: Remove obsolete include/asm symlink step

Pull kbuild changes from Michal Marek:
 - fix for handling dependencies of *-objs targets by Masahiro Yamada
 - lots of cleanups in the kbuild machinery, also by Masahiro
 - fixes for the kconfig build to use an UTF-8 capable ncurses library
   if possible and to build on not-so-standard installs
 - some more minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Do not reference *-n variables in the Makefile
  kbuild: simplify build, clean, modbuiltin shorthands
  kbuild: arm: Do not define "comma" twice
  kbuild: remove obj-n and lib-n handling
  kbuild: remove unnecessary variable initializaions
  kbuild: remove unnecessary "obj- := dummy.o" trick
  kbuild: handle C=... and M=... after entering into build directory
  kbuild: use $(Q) for sub-make target
  kbuild: fake the "Entering directory ..." message more simply
  kconfig/lxdialog: get ncurses CFLAGS with pkg-config
  kconfig: nconfig: fix multi-byte UTF handling
  kconfig: lxdialog: fix spelling
  kbuild: Make scripts executable
  kbuild: remove redundant clean-files from scripts/kconfig/Makefile
  kbuild: refactor script/kconfig/Makefile
  kbuild: handle the dependency of multi-objs hostprogs appropriately
  kbuild: handle multi-objs dependency appropriately

Merge tag 'fscache-fixes-20141013' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fs-cache fixes from David Howells:
 "Two fixes for bugs in CacheFiles and a cleanup in FS-Cache"

* tag 'fscache-fixes-20141013' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fs/fscache/object-list.c: use __seq_open_private()
  CacheFiles: Fix incorrect test for in-memory object collision
  CacheFiles: Handle object being killed before being set up

Pull UBI/UBIFS fixes from Artem Bityutskiy:
 - fix for a theoretical race condition which could lead to a situation
   when UBIFS is unable to mount a file-system (Hujianyang)
 - a few fixes for the ubiblock sybsystem, error path fixes
 - the ubiblock subsystem has had the volume size change handling
   improved
 - a few fixes and nicifications in the fastmap subsystem

* tag 'upstream-3.18-rc1-v2' of git://git.infradead.org/linux-ubifs:
  UBI: Fastmap: Calc fastmap size correctly
  UBIFS: Fix trivial typo in power_cut_emulated()
  UBI: Fix trivial typo in __schedule_ubi_work
  UBI: wl: Rename cancel flag to shutdown
  UBI: ubi_eba_read_leb: Remove in vain variable assignment
  UBIFS: Align the dump messages of SB_NODE
  UBI: Fix livelock in produce_free_peb()
  UBI: return on error in rename_volumes()
  UBI: Improve comment on work_sem
  UBIFS: Remove bogus assert
  UBI: Dispatch update notification if the volume is updated
  UBI: block: Add support for the UBI_VOLUME_UPDATED notification
  UBI: block: Fix block device size setting
  UBI: block: fix dereference on uninitialized dev
  UBI: add missing kmem_cache_free() in process_pool_aeb error path
  UBIFS: fix free log space calculation
  UBIFS: fix a race condition

Pull do_umount fix from Andy Lutomirski:
 "This fix really ought to be safe.  Inside a mountns owned by a
  non-root user namespace, the namespace root almost always has
  MNT_LOCKED set (if it doesn't, then there's a bug, because rootfs
  could be exposed).  In that case, calling umount on "/" will return
  -EINVAL with or without this patch.

  Outside a userns, this patch will have no effect.  may_mount, required
  by umount, already checks
     ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN)
  so an additional capable(CAP_SYS_ADMIN) check will have no effect.

  That leaves anything that calls umount on "/" in a non-root userns
  while chrooted.  This is the case that is currently broken (it
  remounts ro, which shouldn't be allowed) and that my patch changes to
  -EPERM.  If anything relies on *that*, I'd be surprised"

* 'CVE-2014-7975' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux:
  fs: Add a missing permission check to do_umount

Merge second patch-bomb from Andrew Morton:
 - a few hotfixes
 - drivers/dma updates
 - MAINTAINERS updates
 - Quite a lot of lib/ updates
 - checkpatch updates
 - binfmt updates
 - autofs4
 - drivers/rtc/
 - various small tweaks to less used filesystems
 - ipc/ updates
 - kernel/watchdog.c changes

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (135 commits)
  mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared
  kernel/param: consolidate __{start,stop}___param[] in <linux/moduleparam.h>
  ia64: remove duplicate declarations of __per_cpu_start[] and __per_cpu_end[]
  frv: remove unused declarations of __start___ex_table and __stop___ex_table
  kvm: ensure hard lockup detection is disabled by default
  kernel/watchdog.c: control hard lockup detection default
  staging: rtl8192u: use %*pEn to escape buffer
  staging: rtl8192e: use %*pEn to escape buffer
  staging: wlan-ng: use %*pEhp to print SN
  lib80211: remove unused print_ssid()
  wireless: hostap: proc: print properly escaped SSID
  wireless: ipw2x00: print SSID via %*pE
  wireless: libertas: print esaped string via %*pE
  lib/vsprintf: add %*pE[achnops] format specifier
  lib / string_helpers: introduce string_escape_mem()
  lib / string_helpers: refactoring the test suite
  lib / string_helpers: move documentation to c-file
  include/linux: remove strict_strto* definitions
  arch/x86/mm/numa.c: fix boot failure when all nodes are hotpluggable
  fs: check bh blocknr earlier when searching lru
  ...

Pull m68knommu update from Greg Ungerer:
 "The major change is to remove the arch/m68k/platform directory.  The
  coldfire (and other non-mmu m68k platform) code is moved to the
  arch/m68k level, making them consistent with the traditional m68k
  platforms.

  A couple of other minor miscellaneous fixes as well"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: Fix typo 'COFNIG_MBAR'
  m68knommu: add missing ioport_map() and ioport_unmap()
  m68k/coldfire: remove second asm/mcfclk.h inclusion in m54xx.c
  m68knommu: fix size of address field for 5272 interrupt controller
  m68k: fix crufty 68000 and 68360 intro comments
  m68k: remove the unused arch/m68k/platform directory
  m68k: move non-mmu 68360 platform code
  m68k: move non-mmu 68000 platform code
  m68k: fix crufty ColdFire intro comments
  m68k: move coldfire platform code

Pull ia64 update from Tony Luck:
 "Wire up bpf syscall for ia64"

* tag 'please-pull-sys_bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  [IA64] Enable bpf syscall for ia64

Pull UML update from Richard Weinberger:
 "Besides of fixes this contains also support for CONFIG_STACKTRACE by
  Daniel Walter"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: net: Eliminate NULL test after alloc_bootmem
  um: Add support for CONFIG_STACKTRACE
  um: ubd: Fix for processes stuck in D state forever
  um: delete unnecessary bootmem struct page array
  um: remove csum_partial_copy_generic_i386 to clean up exception table

Pull s390 updates from Martin Schwidefsky:
 "This patch set contains the main portion of the changes for 3.18 in
  regard to the s390 architecture.  It is a bit bigger than usual,
  mainly because of a new driver and the vector extension patches.

  The interesting bits are:
   - Quite a bit of work on the tracing front.  Uprobes is enabled and
     the ftrace code is reworked to get some of the lost performance
     back if CONFIG_FTRACE is enabled.
   - To improve boot time with CONFIG_DEBIG_PAGEALLOC, support for the
     IPTE range facility is added.
   - The rwlock code is re-factored to improve writer fairness and to be
     able to use the interlocked-access instructions.
   - The kernel part for the support of the vector extension is added.
   - The device driver to access the CD/DVD on the HMC is added, this
     will hopefully come in handy to improve the installation process.
   - Add support for control-unit initiated reconfiguration.
   - The crypto device driver is enhanced to enable the additional AP
     domains and to allow the new crypto hardware to be used.
   - Bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (39 commits)
  s390/ftrace: simplify enabling/disabling of ftrace_graph_caller
  s390/ftrace: remove 31 bit ftrace support
  s390/kdump: add support for vector extension
  s390/disassembler: add vector instructions
  s390: add support for vector extension
  s390/zcrypt: Toleration of new crypto hardware
  s390/idle: consolidate idle functions and definitions
  s390/nohz: use a per-cpu flag for arch_needs_cpu
  s390/vtime: do not reset idle data on CPU hotplug
  s390/dasd: add support for control unit initiated reconfiguration
  s390/dasd: fix infinite loop during format
  s390/mm: make use of ipte range facility
  s390/setup: correct 4-level kernel page table detection
  s390/topology: call set_sched_topology early
  s390/uprobes: architecture backend for uprobes
  s390/uprobes: common library for kprobes and uprobes
  s390/rwlock: use the interlocked-access facility 1 instructions
  s390/rwlock: improve writer fairness
  s390/rwlock: remove interrupt-enabling rwlock variant.
  s390/mm: remove change bit override support
  ...

Merge branches 'x86-ras-for-linus', 'x86-uv-for-linus' and 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 ras, uv and vdso fixlets from Ingo Molnar:
 "ras: tone down a kernel message to only occur during initial bootup,
    not during suspend/resume cycles.

  uv: a cleanup commit

  vdso: a fix to error checking"

* 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Avoid showing repetitive message from intel_init_thermal()

* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic/uv: Remove unnecessary #ifdef

* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vdso: Fix vdso2c's special_pages[] error checking

Pull x86 fixes from Ingo Molnar:
 "Misc smaller fixes that missed the v3.17 cycle"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build: Add arch/x86/purgatory/ make generated files to gitignore
  x86: Fix section conflict for numachip
  x86: Reject x32 executables if x32 ABI not supported
  x86_64, entry: Filter RFLAGS.NT on entry from userspace
  x86, boot, kaslr: Fix nuisance warning on 32-bit builds

Pull x86 seccomp changes from Ingo Molnar:
 "This tree includes x86 seccomp filter speedups and related preparatory
  work, which touches core seccomp facilities as well.

  The main idea is to split seccomp into two phases, to be able to enter
  a simple fast path for syscalls with ptrace side effects.

  There's no substantial user-visible (and ABI) effects expected from
  this, except a change in how we emit a better audit record for
  SECCOMP_RET_TRACE events"

* 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86_64, entry: Use split-phase syscall_trace_enter for 64-bit syscalls
  x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls
  x86: Split syscall_trace_enter into two phases
  x86, entry: Only call user_exit if TIF_NOHZ
  x86, x32, audit: Fix x32's AUDIT_ARCH wrt audit
  seccomp: Document two-phase seccomp and arch-provided seccomp_data
  seccomp: Allow arch code to provide seccomp_data
  seccomp: Refactor the filter callback and the API
  seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing

Pull x86 platform updates from Ingo Molnar:
 "The main changes in this tree are:

   - fix and update Intel Quark [Galileo] SoC platform support

   - update IOSF chipset side band interface and make it available via
     debugfs

   - enable HPETs on Soekris net6501 and other e6xx based systems"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Add cpu_detect_cache_sizes to init_intel() add Quark legacy_cache()
  x86: Quark: Comment setup_arch() to document TLB/PGE bug
  x86/intel/quark: Switch off CR4.PGE so TLB flush uses CR3 instead
  x86/platform/intel/iosf: Add debugfs config option for IOSF
  x86/platform/intel/iosf: Add better description of IOSF driver in config
  x86/platform/intel/iosf: Add Braswell PCI ID
  x86/platform/pmc_atom: Fix warning when CONFIG_DEBUG_FS=n
  x86: HPET force enable for e6xx based systems
  x86/iosf: Add debugfs support
  x86/iosf: Add Kconfig prompt for IOSF_MBI selection

Pull x86 mm updates from Ingo Molnar:
 "This tree includes the following changes:

   - fix memory hotplug
   - fix hibernation bootup memory layout assumptions
   - fix hyperv numa guest kernel messages
   - remove dead code
   - update documentation"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Update memory map description to list hypervisor-reserved area
  x86/mm, hibernate: Do not assume the first e820 area to be RAM
  x86/mm/numa: Drop dead code and rename setup_node_data() to setup_alloc_data()
  x86/mm/hotplug: Modify PGD entry when removing memory
  x86/mm/hotplug: Pass sync_global_pgds() a correct argument in remove_pagetable()
  x86: Remove set_pmd_pfn

Pull x86 microcode loading updates from Ingo Molnar:
 "Misc smaller cleanups"

* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode, intel: Fix total_size computation
  x86, microcode, intel: Rename apply_microcode and declare it static
  x86, microcode, intel: Fix typos
  x86, microcode, intel: Add missing static declarations
  x86, microcode, amd: Fix missing static declaration

Pull x86 FPU updates from Ingo Molnar:
 "x86 FPU handling fixes, cleanups and enhancements from Oleg.

  The signal handling race fix and the __restore_xstate_sig() preemption
  fix for eager-mode is marked for -stable as well"

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: copy_thread: Don't nullify ->ptrace_bps twice
  x86, fpu: Shift "fpu_counter = 0" from copy_thread() to arch_dup_task_struct()
  x86, fpu: copy_process: Sanitize fpu->last_cpu initialization
  x86, fpu: copy_process: Avoid fpu_alloc/copy if !used_math()
  x86, fpu: Change __thread_fpu_begin() to use use_eager_fpu()
  x86, fpu: __restore_xstate_sig()->math_state_restore() needs preempt_disable()
  x86, fpu: shift drop_init_fpu() from save_xstate_sig() to handle_signal()

Pull x86 cpufeature updates from Ingo Molnar:
 "This tree includes the following changes:

   - Introduce DISABLED_MASK to list disabled CPU features, to simplify
     CPU feature handling and avoid excessive #ifdefs

   - Remove the lightly used cpu_has_pae() primitive"

* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Add more disabled features
  x86: Introduce disabled-features
  x86: Axe the lightly-used cpu_has_pae

For VMAs that don't want write notifications, PTEs created for read faults
have their write bit set.  If the read fault happens after VM_SOFTDIRTY is
cleared, then the PTE's softdirty bit will remain clear after subsequent
writes.

Here's a simple code snippet to demonstrate the bug:

  char* m = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE,
                 MAP_ANONYMOUS | MAP_SHARED, -1, 0);
  system("echo 4 > /proc/$PPID/clear_refs"); /* clear VM_SOFTDIRTY */
  assert(*m == '\0');     /* new PTE allows write access */
  assert(!soft_dirty(x));
  *m = 'x';               /* should dirty the page */
  assert(soft_dirty(x));  /* fails */

With this patch, write notifications are enabled when VM_SOFTDIRTY is
cleared.  Furthermore, to avoid unnecessary faults, write notifications
are disabled when VM_SOFTDIRTY is set.

As a side effect of enabling and disabling write notifications with
care, this patch fixes a bug in mprotect where vm_page_prot bits set by
drivers were zapped on mprotect.  An analogous bug was fixed in mmap by
commit c9d0bf24 ("mm: uncached vma support with writenotify").
Signed-off-by: Peter Feiner <pfeiner@google.com>
Reported-by: Peter Feiner <pfeiner@google.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Jamie Liu <jamieliu@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Consolidate the various external const and non-const declarations of
__start___param[] and __stop___param in <linux/moduleparam.h>.  This
requires making a few struct kernel_param pointers in kernel/params.c
const.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

They're already provided by <asm/sections.h>.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use watchdog_enable_hardlockup_detector() to set hard lockup detection's
default value to false.  It's risky to run this detection in a guest, as
false positives are easy to trigger, especially if the host is
overcommitted.
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In some cases we don't want hard lockup detection enabled by default.
An example is when running as a guest.  Introduce

  watchdog_enable_hardlockup_detector(bool)

allowing those cases to disable hard lockup detection.  This must be
executed early by the boot processor from e.g.  smp_prepare_boot_cpu, in
order to allow kernel command line arguments to override it, as well as
to avoid hard lockup detection being enabled before we've had a chance
to indicate that it's unwanted.  In summary,

  initial boot:					default=enabled
  smp_prepare_boot_cpu
    watchdog_enable_hardlockup_detector(false):	default=disabled
  cmdline has 'nmi_watchdog=1':			default=enabled

The running kernel still has the ability to enable/disable at any time
with /proc/sys/kernel/nmi_watchdog us usual.  However even when the
default has been overridden /proc/sys/kernel/nmi_watchdog will initially
show '1'.  To truly turn it on one must disable/enable it, i.e.

  echo 0 > /proc/sys/kernel/nmi_watchdog
  echo 1 > /proc/sys/kernel/nmi_watchdog

This patch will be immediately useful for KVM with the next patch of this
series.  Other hypervisor guest types may find it useful as well.

[akpm@linux-foundation.org: fix build]
[dzickus@redhat.com: fix compile issues on sparc]
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Let's use kernel's native specifier to escape a buffer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Let's use kernel's native specifier to escape a buffer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is a generic specifier to print an escaped buffer by given criteria.
Let's use it instead of custom approach.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In kernel we have %*pE specifier to print an escaped buffer.  All users
now switched to that approach.

This fixes a bug as well.  The current implementation wrongly prints
octal numbers: only two first digits are used in case when 3 are
required and the rest of the string ends up cut off.

Additionally by default the \f, \v, \a, and \e are escaped to their
alphabetic representation.  It's safe to do since it is currently used
for messaging only.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Instead of substituting non-printable characters by '_' let's print SSID
properly escaped by using recently added %*pE specifier.

[akpm@linux-foundation.org: fix printk type warning]
[akpm@linux-foundation.org: remove now-unused local `i']
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Instead of custom approach this allows to print escaped strings via
recently added kernel extension: %*pE.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Instead of custom approach this allows to print escaped strings via
recently added kernel extension: %*pE.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This allows user to print a given buffer as an escaped string.  The
rules are applied according to an optional mix of flags provided by
additional format letters.

For example, if the given buffer is:

    1b 62 20 5c 43 07 22 90 0d 5d

The result strings would be:
    %*pE            "\eb \C\a"\220\r]"
    %*pEhp          "\x1bb \C\x07"\x90\x0d]"
    %*pEa           "\e\142\040\\\103\a\042\220\r\135"

Please, read Documentation/printk-formats.txt and lib/string_helpers.c
kernel documentation to get further information.

[akpm@linux-foundation.org: tidy up comment layout, per Joe]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Joe Perches <joe@perches.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is almost the opposite function to string_unescape().  Nevertheless
it handles \0 and could be used for any byte buffer.

The documentation is supplied together with the function prototype.

The test cases covers most of the scenarios and would be expanded later
on.

[akpm@linux-foundation.org: avoid 1k stack consumption]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This patch prepares test suite for a following update.  It introduces
test_string_check_buf() helper which checks the result and dumps an error.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The introduced function string_escape_mem() is a kind of opposite to
string_unescape.  We have several users of such functionality each of
them created custom implementation.  The series contains clean up of
test suite, adding new call, and switching few users to use it via %*pE
specifier.

Test suite covers all of existing and most of potential use cases.

This patch (of 11):

The documentation of API belongs to c-file.  This patch moves it
accordingly.

There is no functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "John W . Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Remove obsolete and unused strict_strto* functions
Signed-off-by: Daniel Walter <dwalter@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If all the nodes are marked hotpluggable, alloc node data will fail.
Because __next_mem_range_rev() will skip the hotpluggable memory
regions.  numa_clear_kernel_node_hotplug() is called after alloc node
data.

numa_init()
    ...
    ret = init_func();  // this will mark hotpluggable flag from SRAT
    ...
    memblock_set_bottom_up(false);
    ...
    ret = numa_register_memblks(&numa_meminfo);  // this will alloc node data(pglist_data)
    ...
    numa_clear_kernel_node_hotplug();  // in case all the nodes are hotpluggable
    ...

numa_register_memblks()
    setup_node_data()
        memblock_find_in_range_node()
            __memblock_find_range_top_down()
                for_each_mem_range_rev()
                    __next_mem_range_rev()

This patch moves numa_clear_kernel_node_hotplug() into
numa_register_memblks(), clear kernel node hotpluggable flag before
alloc node data, then alloc node data won't fail even all the nodes
are hotpluggable.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

It's very common for the buffer heads in the lru to have different block
numbers.  By comparing the blocknr before the bdev and size we can
reduce the cost of searching in the very common case where all the
entries have the same bdev and size.

In quick hot cache cycle counting tests on a single fs workstation this
cut the cost of a miss by about 20%.

A diff of the disassembly shows the reordering of the bdev and blocknr
comparisons.  This is in such a tiny loop that skipping one comparison
is a meaningful portion of the total work being done:

     1628:      83 c1 01                add    $0x1,%ecx
     162b:      83 f9 08                cmp    $0x8,%ecx
     162e:      74 60                   je     1690 <__find_get_block+0xa0>
     1630:      89 c8                   mov    %ecx,%eax
     1632:      65 4c 8b 04 c5 00 00    mov    %gs:0x0(,%rax,8),%r8
     1639:      00 00
     163b:      4d 85 c0                test   %r8,%r8
     163e:      4c 89 c3                mov    %r8,%rbx
     1641:      74 e5                   je     1628 <__find_get_block+0x38>
-    1643:      4d 3b 68 30             cmp    0x30(%r8),%r13
+    1643:      4d 3b 68 18             cmp    0x18(%r8),%r13
     1647:      75 df                   jne    1628 <__find_get_block+0x38>
-    1649:      4d 3b 60 18             cmp    0x18(%r8),%r12
+    1649:      4d 3b 60 30             cmp    0x30(%r8),%r12
     164d:      75 d9                   jne    1628 <__find_get_block+0x38>
     164f:      49 39 50 20             cmp    %rdx,0x20(%r8)
     1653:      75 d3                   jne    1628 <__find_get_block+0x38>
Signed-off-by: Zach Brown <zab@zabbo.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>