Add a new interface, add_device_randomness() for adding data to the
random pool that is likely to differ between two devices (or possibly
even per boot).  This would be things like MAC addresses or serial
numbers, or the read-out of the RTC. This does *not* add any actual
entropy to the pool, but it initializes the pool to different values
for devices that might otherwise be identical and have very little
entropy available to them (particularly common in the embedded world).

[ Modified by tytso to mix in a timestamp, since there may be some
  variability caused by the time needed to detect/configure the hardware
  in question. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

The real-time Linux folks don't like add_interrupt_randomness() taking
a spinlock since it is called in the low-level interrupt routine.
This also allows us to reduce the overhead in the fast path, for the
random driver, which is the interrupt collection path.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

We've been moving away from add_interrupt_randomness() for various
reasons: it's too expensive to do on every interrupt, and flooding the
CPU with interrupts could theoretically cause bogus floods of entropy
from a somewhat externally controllable source.

This solves both problems by limiting the actual randomness addition
to just once a second or after 64 interrupts, whicever comes first.
During that time, the interrupt cycle data is buffered up in a per-cpu
pool.  Also, we make sure the the nonblocking pool used by urandom is
initialized before we start feeding the normal input pool.  This
assures that /dev/urandom is returning unpredictable data as soon as
possible.

(Based on an original patch by Linus, but significantly modified by
tytso.)
Tested-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Nadia Heninger <nadiah@cs.ucsd.edu>
Reported-by: Zakir Durumeric <zakir@umich.edu>
Reported-by: J. Alex Halderman <jhalderm@umich.edu>.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Add extern and static declarations to suppress sparse warnings
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Pull ARM SoC fixes from Olof Johansson:
 "Another week, another batch of fixes.

  All are small, contained, targeted fixes for explicit problems --
  mostly build and boot failures across i.MX, OMAP, Renesas/Shmobile and
  Samsung."

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: imx6q: fix suspend regression caused by common clk migration
  ARM: OMAP4470: Fix OMAP4470 boot failure
  ARM: EXYNOS: Fix EXYNOS_DEV_DMA Kconfig entry
  ARM: OMAP2+: nand: fix build error when CONFIG_MTD_ONENAND_OMAP2=n
  ARM: shmobile: r8a7779: Route all interrupts to ARM
  ARM: shmobile: kzm9d: use late init machine hook
  ARM: shmobile: kzm9g: use late init machine hook
  ARM: mach-shmobile: armadillo800eva: Use late init machine hook
  ARM: SAMSUNG: Fix for S3C2412 EBI memory mapping
  ARM: mach-shmobile: add missing GPIO IRQ configuration on mackerel
  ARM: mach-shmobile: Fix build when SMP is enabled and EMEV2 is not enabled
  ARM: shmobile: sh7372: bugfix: chclr_offset base
  ARM: shmobile: sh73a0: bugfix: SY-DMAC number
  ARM: SAMSUNG: Should check for IS_ERR(clk) instead of NULL

Fix kernel-doc warnings in printk.c: use correct parameter name.

  Warning(kernel/printk.c:2429): No description found for parameter 'buf'
  Warning(kernel/printk.c:2429): Excess function parameter 'line' description in 'kmsg_dump_get_buffer'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warning.  This struct member was removed in commit
87568264 ("irq: Remove irq_chip->release()") so remove its
associated kernel-doc entry also.

  Warning(include/linux/irq.h:338): Excess struct/union/enum/typedef member 'release' description in 'irq_chip'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'v3.5-samsung-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes

* 'v3.5-samsung-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: EXYNOS: Fix EXYNOS_DEV_DMA Kconfig entry
  ARM: SAMSUNG: Fix for S3C2412 EBI memory mapping
  ARM: SAMSUNG: Should check for IS_ERR(clk) instead of NULL

When moving to common clk framework, the imx6q clks rom and mmdc_ch1_axi
get different on/off states than old clk driver, which breaks suspend
function.  There might be a better way to manage these clocks, but let's
takes the old clk driver approach to fix the regression first.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'omap-fixes-for-v3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

From Tony Lindgren:
"Here's one more regression fix that I missed earlier, and a
 trivial fix to get omap4470 booting."

* tag 'omap-fixes-for-v3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP4470: Fix OMAP4470 boot failure
  ARM: OMAP2+: nand: fix build error when CONFIG_MTD_ONENAND_OMAP2=n

Pull ACPI & Power Management patches from Len Brown.

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  acpi_pad: fix power_saving thread deadlock
  ACPI video: Still use ACPI backlight control if _DOS doesn't exist
  ACPI, APEI, Avoid too much error reporting in runtime
  ACPI: Add a quirk for "AMILO PRO V2030" to ignore the timer overriding
  ACPI: Remove one board specific WARN when ignoring timer overriding
  ACPI: Make acpi_skip_timer_override cover all source_irq==0 cases
  ACPI, x86: fix Dell M6600 ACPI reboot regression via DMI
  ACPI sysfs.c strlen fix

Pull driver Core fixes from Greg Kroah-Hartman:
 "Here is a number of printk() fixes, specifically a few reported by the
  crazy blog program that ships in SUSE releases (that's "boot log" and
  not "web log", it predates the general "blog" terminology by many
  years), and the restoration of the continuation line functionality
  reported by Stephen and others.  Yes, the changes seem a bit big this
  late in the cycle, but I've been beating on them for a while now, and
  Stephen has even optimized it a bit, so all looks good to me.

  The other change in here is a Documentation update for the stable
  kernel rules describing how some distro patches should be backported,
  to hopefully drive a bit more response from the distros to the stable
  kernel releases.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  printk: Optimize if statement logic where newline exists
  printk: flush continuation lines immediately to console
  syslog: fill buffer with more than a single message for SYSLOG_ACTION_READ
  Revert "printk: return -EINVAL if the message len is bigger than the buf size"
  printk: fix regression in SYSLOG_ACTION_CLEAR
  stable: Allow merging of backports for serious user-visible performance issues

Merge branches 'acpi_pad-bugzilla-42981', 'apei-bugzilla-43282', 'video-bugzilla-43168', 'bugzilla-40002' and 'bugfix-misc' into release

bug fixes

The acpi_pad driver can get stuck in destroy_power_saving_task()
waiting for kthread_stop() to stop a power_saving thread.  The problem
is that the isolated_cpus_lock mutex is owned when
destroy_power_saving_task() calls kthread_stop(), which waits for a
power_saving thread to end, and the power_saving thread tries to
acquire the isolated_cpus_lock when it calls round_robin_cpu().  This
patch fixes the issue by making round_robin_cpu() use its own mutex.

https://bugzilla.kernel.org/show_bug.cgi?id=42981

Cc: stable@vger.kernel.org
Signed-off-by: Stuart Hayes <Stuart_Hayes@Dell.com>
Signed-off-by: Len Brown <len.brown@intel.com>

This fixes a regression in 3.4-rc1 caused by commit
ea9f8856
(ACPI video: Harden video bus adding.)

Some platforms don't have _DOS control method, but the ACPI
backlight still works.
We should not invoke _DOS for these platforms.

https://bugzilla.kernel.org/show_bug.cgi?id=43168

Cc: Igor Murzov <intergalactic.anonymous@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Pull power management fixes from Rafael J. Wysocki:

 * Fix for a bug in async suspend error code path causing parents to
   wait forever for their children in case of a suspend error from
   Mandeep Singh Baines (-stable metarial).

 * Fix for a suspend regression related to earlier changes in the ACPI
   cpuidle driver from Deepthi Dharwar.

* tag 'pm-for-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup.
  PM / Sleep: Prevent waiting forever on asynchronous suspend after abort

In reviewing Kay's fix up patch: "printk: Have printk() never buffer its
data", I found two if statements that could be combined and optimized.

Put together the two 'cont.len && cont.owner == current' if statements
into a single one, and check if we need to call cont_add(). This also
removes the unneeded double cont_flush() calls.

Link: http://lkml.kernel.org/r/1340869133.876.10.camel@mopSigned-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull powerpc fixes from Benjamin Herrenschmidt:
 "Here are a few powerpc fixes.  Arguably some of this should have come
  to you earlier but I'm only just catching up after my medical leave.

  Mostly these fixes regressions, a couple are long standing bugs."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/pseries: Fix software invalidate TCE
  powerpc: check_and_cede_processor() never cedes
  powerpc/ftrace: Do not trace restore_interrupts()
  powerpc: Fix Section mismatch warnings in prom_init.c
  ppc64: fix missing to check all bits of _TIF_USER_WORK_MASK in preempt
  powerpc: Fix uninitialised error in numa.c
  powerpc: Fix BPF_JIT code to link with multiple TOCs

Pull x86 fixes from Ingo Molnar.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpufeature: Remove stray %s, add -w to mkcapflags.pl
  x86, cpufeature: Catch duplicate CPU feature strings
  x86, cpufeature: Rename X86_FEATURE_DTS to X86_FEATURE_DTHERM
  x86: Fix kernel-doc warnings
  x86, compat: Use test_thread_flag(TIF_IA32) in compat signal delivery

Pull oprofile fixlet from Ingo Molnar.

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  oprofile: perf: use NR_CPUS instead or nr_cpumask_bits for static array

Pull RCU fix from Ingo Molnar.

Fixes a bug introduced in this merge window by commit b1420f1c ("Make
rcu_barrier() less disruptive")

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Stop rcu_do_batch() from multiplexing the "count" variable

Continuation lines are buffered internally, intended to merge the
chunked printk()s into a single record, and to isolate potentially
racy continuation users from usual terminated line users.

This though, has the effect that partial lines are not printed to
the console in the moment they are emitted. In case the kernel
crashes in the meantime, the potentially interesting printed
information would never reach the consoles.

Here we share the continuation buffer with the console copy logic,
and partial lines are always immediately flushed to the available
consoles. They are still buffered internally to improve the
readability and integrity of the messages and minimize the amount
of needed record headers to store.
Signed-off-by: Kay Sievers <kay@vrfy.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The following added support for powernv but broke pseries/BML:
 1f1616e8 powerpc/powernv: Add TCE SW invalidation support

TCE_PCI_SW_INVAL was split into FREE and CREATE flags but the tests in
the pseries code were not updated to reflect this.
Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@kernel.org [v3.3+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Commit f948501b ("Make hard_irq_disable() actually hard-disable
interrupts") caused check_and_cede_processor to stop working.
->irq_happened will never be zero right after a hard_irq_disable
so the compiler removes the call to cede_processor completely.

The bug was introduced back in the lazy interrupt handling rework
of 3.4 but was hidden until recently because hard_irq_disable did
nothing.

This issue will eventually appear in 3.4 stable since the
hard_irq_disable fix is marked stable, so mark this one for stable
too.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

As I was adding code that affects all archs, I started testing function
tracer against PPC64 and found that it currently locks up with 3.4
kernel. I figured it was due to tracing a function that shouldn't be, so
I went through the following process to bisect to find the culprit:

 cat /debug/tracing/available_filter_functions > t
 num=`wc -l t`
 sed -ne "1,${num}p" t > t1
 let num=num+1
 sed -ne "${num},$p" t > t2
 cat t1 > /debug/tracing/set_ftrace_filter
 echo function /debug/tracing/current_tracer
 <failed? bisect t1, if not bisect t2>

It finally came down to this function: restore_interrupts()

I'm not sure why this locks up the system. It just seems to prevent
scheduling from occurring. Interrupts seem to still work, as I can ping
the box. But all user processes freeze.

When restore_interrupts() is not traced, function tracing works fine.

Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patches tries to fix a couple of Section mismatch warnings like
following one:

WARNING: arch/powerpc/kernel/built-in.o(.text+0x2923c): Section mismatch
in reference from the function .prom_query_opal() to the
function .init.text:.call_prom()
The function .prom_query_opal() references
the function __init .call_prom().
This is often because .prom_query_opal lacks a __init
annotation or the annotation of .call_prom is wrong.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

In entry_64.S version of ret_from_except_lite, you'll notice that
in the !preempt case, after we've checked MSR_PR we test for any
TIF flag in _TIF_USER_WORK_MASK to decide whether to go to do_work
or not. However, in the preempt case, we do a convoluted trick to
test SIGPENDING only if PR was set and always test NEED_RESCHED ...
but we forget to test any other bit of _TIF_USER_WORK_MASK !!! So
that means that with preempt, we completely fail to test for things
like single step, syscall tracing, etc...

This should be fixed as the following path:

 - Test PR. If not set, go to resume_kernel, else continue.

 - If go resume_kernel, to do that original do_work.

 - If else, then always test for _TIF_USER_WORK_MASK to decide to do
that original user_work, else restore directly.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

chroma_defconfig currently gives me this with gcc 4.6:
  arch/powerpc/mm/numa.c:638:13: error: 'dm' may be used uninitialized in this function [-Werror=uninitialized]

It's a bogus warning/error since of_get_drconf_memory() only writes it
anyway.
Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: <stable@kernel.org> [v3.3+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

If the kernel is big enough (eg. allyesconfig), the linker may need to
switch TOCs when calling from the BPF JIT code out to the external
helpers (skb_copy_bits() & bpf_internal_load_pointer_neg_helper()).

In order to do that we need to leave space after the bl for the linker
to insert a reload of our TOC pointer.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Pull hwmon changes from Guenter Roeck:
 "Just e-mail address updates"

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: Update my e-mail address
  hwmon: (applesmc) correct email address for Jesper Juhl

Pull watchdog fixes from Wim Van Sebroeck:
 "This fixes:
   - the WDIOC_GETSTATUS return value
   - the unregister of all NMI events on exit
   - the loading of the iTCO_wdt driver after the conversion to the
     lpc_ich mfd model."

* git://www.linux-watchdog.org/linux-watchdog:
  watchdog: core: fix WDIOC_GETSTATUS return value
  watchdog: hpwdt: Unregister NMI events on exit.
  watchdog: iTCO_wdt: add platform driver module alias

Pull UDF fixes from Jan Kara:
 "Make UDF more robust in presence of corrupted filesystem"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fortify loading of sparing table
  udf: Avoid run away loop when partition table length is corrupted
  udf: Use 'ret' instead of abusing 'i' in udf_load_logicalvol()

Pull ubi/ubifs fixes from Artem Bityutskiy:
 "Fix the debugfs regression - we never enable it because incorrect
  'IS_ENABLED()' macro usage: should be 'IS_ENABLED(CONFIG_DEBUG_FS)',
  but we had 'IS_ENABLED(DEBUG_FS)'.  Also fix incorrect assertion."

* tag 'upstream-3.5-rc5' of git://git.infradead.org/linux-ubifs:
  UBI: correct usage of IS_ENABLED()
  UBIFS: correct usage of IS_ENABLED()
  UBIFS: fix assertion

In commit 7a879824 we added
a wrapper for the WDIOC_GETSTATUS ioctl call. The code results
however in a different behaviour: it returns an error if the
driver doesn't support the status operation. This is not
according to the API that says that when we don't support
the status operation, that we just should return a 0 value.
Only when the device isn't there anymore, we should return an
error.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

This patch is to unregister for NMI events upon exit. Also we are now
making the default setting for allow_kdump enabled.
Signed-off-by: Thomas Mingarelli <thomas.mingarelli@hp.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

The recent conversion of iTCO_wdt resulted in the driver no longer
getting loaded automatically, since it no longer has a
MODULE_DEVICE_TABLE() included. As the lpc_ich driver now creates a
platform device, auto-loading can easily be done by having a respective
module alias in place.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Aaron Sierra <asierra@xes-inc.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

Pull drm fixes from Dave Airlie:
 "Nearly all intel, one missing license header in nouveau, nothing
  majorly earth shattering."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  Revert "drm/i915: allow PCH PWM override on IVB"
  drm/nouveau: add license header to prime.
  drm/i915: Fix eDP blank screen after S3 resume on HP desktops
  drm/i915: rip out the PM_IIR WARN

Pull SuperH fixes from Paul Mundt.

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: Convert sh_clk_mstp32_register to sh_clk_mstp_register
  sh: kfr2r09: fix compile breakage

Pull networking update from David Miller:

 1) Pairing and deadlock fixes in bluetooth from Johan Hedberg.

 2) Add device IDs for AR3011 and AR3012 bluetooth chips.  From
    Giancarlo Formicuccia and Marek Vasut.

 3) Fix wireless regulatory deadlock, from Eliad Peller.

 4) Fix full TX ring panic in bnx2x driver, from Eric Dumazet.

 5) Revert the two commits that added skb_orphan_try(), it causes
    erratic bonding behavior with UDP clients and the gains it used to
    give are mostly no longer happening due to how BQL works.  From Eric
    Dumazet.

 6) It took two tries, but Thomas Graf fixed a problem wherein we
    registered ipv6 routing procfs files before their backend data were
    initialized properly.

 7) Fix max GSO size setting in be2net, from Sarveshwar Bandi.

 8) PHY device id mask is wrong for KSZ9021 and KS8001 chips, fix from
    Jason Wang.

 9) Fix use of stale SKB data pointer after skb_linearize() call in
    batman-adv, from Antonio Quartulli.

10) Fix memory leak in IXGBE due to missing __GFP_COMP, from Alexander
    Duyck.

11) Fix probing of Gobi devices in qmi_wwan usbnet driver, from Bjørn
    Mork.

12) Fix suspend/resume and open failure handling in usbnet from Ming
    Lei.

13) Attempt to fix device r8169 hangs for certain chips, from Francois
    Romieu.

14) Fix advancement of RX dirty pointer in some situations in sh_eth
    driver, from Yoshihiro Shimoda.

15) Attempt to fix restart of IPV6 routing table dumps when there is an
    intervening table update.  From Eric Dumazet.

16) Respect security_inet_conn_request() return value in ipv6 TCP.  From
    Neal Cardwell.

17) Add another iPAD device ID to ipheth driver, from Davide Gerhard.

18) Fix access to freed SKB in l2tp_eth_dev_xmit(), and fix l2tp lockdep
    splats, from Eric Dumazet.

19) Make sure all bridge devices, regardless of whether they were
    created via netlink or ioctls, have their rtnetlink ops hooked up.
    From Thomas Graf and Stephen Hemminger.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits)
  9p: fix min_t() casting in p9pdu_vwritef()
  can: flexcan: use be32_to_cpup to handle the value of dt entry
  xen/netfront: teardown the device before unregistering it.
  bridge: Assign rtnl_link_ops to bridge devices created via ioctl (v2)
  vhost: use USER_DS in vhost_worker thread
  ixgbe: Do not pad FCoE frames as this can cause issues with FCoE DDP
  net: l2tp_eth: use LLTX to avoid LOCKDEP splats
  mac802154: add missed braces
  net: l2tp_eth: fix l2tp_eth_dev_xmit race
  net/mlx4_en: Release QP range in free_resources
  net/mlx4: Use single completion vector after NOP failure
  net/mlx4_en: Set correct port parameters during device initialization
  ipheth: add support for iPad
  caif-hsi: Add missing return in error path
  caif-hsi: Bugfix - Piggyback'ed embedded CAIF frame lost
  caif: Clear shutdown mask to zero at reconnect.
  tcp: heed result of security_inet_conn_request() in tcp_v6_conn_request()
  ipv6: fib: fix fib dump restart
  batman-adv: fix race condition in TT full-table replacement
  batman-adv: only drop packets of known wifi clients
  ...