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

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>

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>

If multiple soft offline events hit one free page/hugepage concurrently,
soft_offline_page() can handle the free page/hugepage multiple times,
which makes num_poisoned_pages counter increased more than once.  This
patch fixes this wrong counting by checking TestSetPageHWPoison for normal
papes and by checking the return value of dequeue_hwpoisoned_huge_page()
for hugepages.
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: <stable@vger.kernel.org>	[3.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is a basic driver for the ultra-low-power Abracon AB x80x series of RTC
chips. It supports in particular, the supersets AB0805 and AB1805.
It allows reading and writing the time, and enables the supercapacitor/
battery charger.

[arnd@arndb.de: abx805 depends on i2c]
[alexandre.belloni@free-electrons.com: renam buffer from date to buf in abx80x_rtc_read_time()]
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Document the bindings for abracon,abx80x and related compatibles.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Philippe De Muyter <phdm@macqel.be>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The documentation shows a need for gcc > 4.9.2, but it's really >=.  The
Kconfig entries don't show require versions so add them.  Correct a
latter/later typo too.  Also mention that gcc 5 required to catch out of
bounds accesses to global and stack variables.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently memory_failure() calls shake_page() to sweep pages out from
pcplists only when the victim page is 4kB LRU page or thp head page.
But we should do this for a thp tail page too.

Consider that a memory error hits a thp tail page whose head page is on
a pcplist when memory_failure() runs.  Then, the current kernel skips
shake_pages() part, so hwpoison_user_mappings() returns without calling
split_huge_page() nor try_to_unmap() because PageLRU of the thp head is
still cleared due to the skip of shake_page().

As a result, me_huge_page() runs for the thp, which is broken behavior.

One effect is a leak of the thp.  And another is to fail to isolate the
memory error, so later access to the error address causes another MCE,
which kills the processes which used the thp.

This patch fixes this problem by calling shake_page() for thp tail case.

Fixes: 385de357 ("thp: allow a hwpoisoned head page to be put back to LRU")
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Dean Nelson <dnelson@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Cc: <stable@vger.kernel.org>	[3.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The file lib/find_last_bit.c was no longer used and supposed to be
deleted by commit 8f6f19dd ("lib: move find_last_bit to
lib/find_next_bit.c") but that delete didn't happen.  This gets rid of
it.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add myself (Jacek Anaszewski) as a co-maintainer for the LED subsystem.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Sergey Senozhatsky has contributed/reviewed to zram for a long time.  He
is really helpful for maintaining zram so I want for him to continue
helping me as Designated Reviewer unless he hates it.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Revert commit c72c6160

It was intended to be a cosmetic change that w/o any functional change
and was part of a bigger change:

  http://lkml.iu.edu/hypermail/linux/kernel/1503.1/01818.html

Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix the following warning:

warning: "static" is not at beginning of declaration
 void static hotkey_mask_warn_incomplete_mask(void)
 ^
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Henrique de Moraes Holschuh <ibm-acpi@hmh.eng.br>
Cc: Darren Hart <dvhart@infradead.org>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

Really ignore them by returning -ENODEV from the probe, but not
doing anything.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

commit d6c5dc18 ("ipmi: Remove uses of return value of seq_printf")
incorrectly changed the return value of various proc_show functions
to use seq_has_overflowed().

These functions should return 0 on completion rather than 1/true
on overflow.  1 is the same as #define SEQ_SKIP which would cause
the output to not be emitted (skipped) instead.

This is a logical defect only as the length of these outputs are
all smaller than the initial allocation done by the seq filesystem.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>

Some of the adapters have spaces in their names, but that's really
hard to pass in as a module or kernel parameters.  So ignore the
spaces.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

Returning zero is success.
Signed-off-by: Corey Minyard <cminyard@mvista.com>

Commit 75182b16 ("x86/asm/entry: Switch all C consumers of
kernel_stack to this_cpu_sp0()") changed current_thread_info
to use this_cpu_sp0, and indirectly made it rely on init_tss
which was exported with EXPORT_PER_CPU_SYMBOL_GPL.
As a result some macros and inline functions such as set/get_fs,
test_thread_flag and variants have been made unusable for
external modules.

Make cpu_tss exported with EXPORT_PER_CPU_SYMBOL so that these
functions are accessible again, as they were previously.
Signed-off-by: Marc Dionne <marc.dionne@your-file-system.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1430763404-21221-1-git-send-email-marc.dionne@your-file-system.comSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

Pull crypto fixes from Herbert Xu:
 "This fixes a build problem with bcm63xx and yet another fix to the
  memzero_explicit function to ensure that the memset is not elided"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  hwrng: bcm63xx - Fix driver compilation
  lib: make memzero_explicit more robust against dead store elimination

Pull media fixes from Mauro Carvalho Chehab:
 "Three driver fixes:

   - fix for omap4, fixing a regression due to a subsystem API that got
     removed for 4.1 (commit efde2346);

   - fix for one of the formats supported by Marvel ccic driver;

   - fix rcar_vin driver that, when stopping abnormally, the driver
     can't return from wait_for_completion"

* tag 'media/v4.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] v4l: omap4iss: Replace outdated OMAP4 control pad API with syscon
  [media] media: soc_camera: rcar_vin: Fix wait_for_completion
  [media] marvell-ccic: fix Y'CbCr ordering

Since parse_perf_probe_point() deals with a user passed argument, we
should not assume it to be a valid string.

Without this patch, if pass '' to perf probe, a segfault raises:

 $ perf probe -a ''
 Segmentation fault

This patch checks argument of parse_perf_probe_point() before
string processing.

After this patch:

 $ perf probe -a ''

  usage: perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]
     or: perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]
     ...
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1430210769-94177-1-git-send-email-wangnan0@huawei.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

I spotted two (difficult to hit) bugs while reviewing this.

1)  There is a double free bug because we unregister "map_kset" in
    add_sysfs_runtime_map_entry() and also efi_runtime_map_init().
2)  If we fail to allocate "entry" then we should return
    ERR_PTR(-ENOMEM) instead of NULL.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Guangyu Sun <guangyu.sun@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>