Add the %pK printk format specifier and the /proc/sys/kernel/kptr_restrict
sysctl.

The %pK format specifier is designed to hide exposed kernel pointers,
specifically via /proc interfaces.  Exposing these pointers provides an
easy target for kernel write vulnerabilities, since they reveal the
locations of writable structures containing easily triggerable function
pointers.  The behavior of %pK depends on the kptr_restrict sysctl.

If kptr_restrict is set to 0, no deviation from the standard %p behavior
occurs.  If kptr_restrict is set to 1, the default, if the current user
(intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG
(currently in the LSM tree), kernel pointers using %pK are printed as 0's.
 If kptr_restrict is set to 2, kernel pointers using %pK are printed as
0's regardless of privileges.  Replacing with 0's was chosen over the
default "(null)", which cannot be parsed by userland %p, which expects
"(nil)".

[akpm@linux-foundation.org: check for IRQ context when !kptr_restrict, save an indent level, s/WARN/WARN_ONCE/]
[akpm@linux-foundation.org: coding-style fixup]
[randy.dunlap@oracle.com: fix kernel/sysctl.c warning]
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Thomas Graf <tgraf@infradead.org>
Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For arch which needs USE_GENERIC_SMP_HELPERS, it has to select
USE_GENERIC_SMP_HELPERS, rather than leaving a choice to user, since they
don't provide their own implementions.

Also, move on_each_cpu() to kernel/smp.c, it is strange to put it in
kernel/softirq.c.

For arch which doesn't use USE_GENERIC_SMP_HELPERS, e.g.  blackfin, only
on_each_cpu() is compiled.
Signed-off-by: Amerigo Wang <amwang@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix unusued return value compiler warnings due to unchecked write() calls.

[akpm@linux-foundation.org: correctly handle short writes]
Signed-off-by: Chris Ruffin <cmruffin@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The readmostly section should end at a cacheline aligned address,
otherwise the last several data might share cachline with other data and
make the readmostly data still have cache bounce.

For example, in ia64, secpath_cachep is the last readmostly data, and it
shares cacheline with init_uts_ns.

a000000100e80480 d secpath_cachep
a000000100e80488 D init_uts_ns
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Cc: Will Newton <will.newton@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently, tosh_smm() prototype is present in a header file exported to
userland.  This patch fixes it.
Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Cc: Jonathan Buzzard <jonathan@buzzard.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Michal reports:

In the framebuffer subsystem the abs() macro is often used as a part of
the calculation of a Manhattan metric, which in turn is used as a measure
of similarity between video modes.  The arguments of abs() are sometimes
unsigned numbers.  This worked fine until commit a49c59c0 ("Make sure the
value in abs() does not get truncated if it is greater than 2^32:) , which
changed the definition of abs() to prevent truncation.  As a result of
this change, in the following piece of code:

u32 a = 0, b = 1;
u32 c = abs(a - b);

'c' will end up with a value of 0xffffffff instead of the expected 0x1.

A problem caused by this change and visible by the end user is that
framebuffer drivers relying on functions from modedb.c will fail to find
high resolution video modes similar to that explicitly requested by the
user if an exact match cannot be found (see e.g.

Fix this by special-casing `long' types within abs().

This patch reduces x86_64 code size a bit - drivers/video/uvesafb.o shrunk
by 15 bytes, presumably because it is doing abs() on 4-byte quantities,
and expanding those to 8-byte longs adds code.

testcase:

#define oldabs(x) ({				\
		long __x = (x);			\
		(__x < 0) ? -__x : __x;		\
	})

#define newabs(x) ({						\
		long ret;					\
		if (sizeof(x) == sizeof(long)) {		\
			long __x = (x);				\
			ret = (__x < 0) ? -__x : __x;		\
		} else {					\
			int __x = (x);				\
			ret = (__x < 0) ? -__x : __x;		\
		}						\
		ret;						\
	})

typedef unsigned int u32;

main()
{
	u32 a = 0;
	u32 b = 1;
	u32 oldc = oldabs(a - b);
	u32 newc = newabs(a - b);

	printf("%u %u\n", oldc, newc);
}

akpm:/home/akpm> gcc t.c
akpm:/home/akpm> ./a.out
4294967295 1
Reported-by: Michal Januszewski <michalj@gmail.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Occasionally the system gets into a state where the CMOS clock has gotten
slightly ahead of current time and the periodic update of RTC fails.  The
message is a nuisance and repeats spamming the log.

  See: http://www.ntp.org/ntpfaq/NTP-s-trbl-spec.htm#Q-LINUX-SET-RTC-MMSS

Rather than just removing the message, make it show only once and reduce
severity since it indicates a normal and non urgent condition.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
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>

We need to know the reason why system rebooted in support service.
However, we can't inform our customers of the reason because final
messages are lost on current Linux kernel.

This patch improves the situation above because the final messages are
saved by adding kmsg_dump() to reboot, halt, poweroff and
emergency_restart path.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Reviewed-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This series aims to develop logging facility for enterprise use.

It is important to save kernel messages reliably on enterprise system
because they are helpful for diagnosing system.

This series add kmsg_dump() to the paths loosing kernel messages.  The use
case is the following.

[Use case of reboot/poweroff/halt/emergency_restart]

 My company has often experienced the followings in our support service.
 - Customer's system suddenly reboots.
 - Customers ask us to investigate the reason of the reboot.

We recognize the fact itself because boot messages remain in
/var/log/messages.  However, we can't investigate the reason why the
system rebooted, because the last messages don't remain.  And off course
we can't explain the reason.

We can solve above problem with this patch as follows.

 Case1: reboot with command
   - We can see "Restarting system with command:" or ""Restarting system.".

 Case2: halt with command
   - We can see "System halted.".

 Case3: poweroff with command
   - We can see " Power down.".

 Case4: emergency_restart with sysrq.
   - We can see "Sysrq:" outputted in __handle_sysrq().

 Case5: emergency_restart with softdog.
   - We can see "Initiating system reboot" in watchdog_fire().

So, we can distinguish the reason of reboot, poweroff, halt and emergency_restart.

If customer executed reboot command, you may think the customer should
know the fact.  However, they often claim they don't execute the command
when they rebooted system by mistake.

No message remains on the current Linux kernel, so we can't show the proof
to the customer.  This patch improves this situation.

This patch:

Alters mtdoops and ramoops to perform their actions only for
KMSG_DUMP_PANIC, KMSG_DUMP_OOPS and KMSG_DUMP_KEXEC because they would
like to log crashes only.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Reviewed-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Simplify write file operation for mmapper by using
simple_write_to_buffer().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add missing MODULE_LICENSE():

WARNING: modpost: missing MODULE_LICENSE() in arch/um/drivers/mmapper_kern.o
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Greg Lonnon <glonnon@ridgerun.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

unregister_winch() should use list_for_each_safe(), as it can delete from
the list.
Signed-off-by: Will Newton <will.newton@gmail.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently CONFIG_HIGHMEM is broken on User Mode Linux.  I'm not sure if it
worked ever.

It doesn't compile and this breaks randomconfig testing.
Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The reset command is part of the init sequence and it take effect
only if the lcd is powered.

The effect of the bug was that the sequence:
set lcd power_state to FB_BLANK_POWERDOWN
set lcd power_state to FB_BLANK_UNBLANK
Did not produced a complete reboot of the LCD which was showing fuzzy
colours.

This was not experienced before implementing correctly all the LCD power
states with the patch [1].  Since before the patch [1] the regulators were
not touched and the LCD shutdown was reached with a register write.  After
the patch [1] a complete boot sequence with an initial reset is needed for
the display every time the LCD is powered up.

drivers-video-backlight-l4f00242t03c-full-implement-fb-power-states-for-this-lcd.patch
Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Otherwise a double call to:
$ echo 4 > /sys/class/lcd/l4f00242t03/lcd_power
Will, the first power down the lcd and regulators correctly and the
second produce an unbalanced call to regulator disable.
Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Complete the support of fb power states managing correctly the regulators
bound to this driver.
Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fixes sparse warning:
drivers/video/backlight/l4f00242t03.c:28:21: error: dubious one-bit signed bitfield
Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Extend the LED backlight tirgger driver with an option that allows for
inverting the trigger output polarity.

With the invertion option provided, I (ab)use the backlight trigger for
driving a LED that indicates LCD display blank condtition on my Amstrad
Delta videophone.  Since the machine has no dedicated power LED, it was
not possible to distinguish if the display was blanked, or the machine was
turned off, without touching it.

The invert sysfs control is patterned after a similiar function of the GPIO
trigger driver.

[akpm@linux-foundation.org: make output match input, tighten input checking]
[akpm@linux-foundation.org: make output match input, tighten input checking]
Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently the led device name is fetched from the device_type in
I2C_BOARD_INFO which comes from the platform data.  This name is in turn
used to create an entry in sysfs.

If there exists two or more lp5521 on a particular platform, the
device_type in I2C_BOARD_INFO has to be the same, else lp5521 driver probe
wont be called and if used so, results in run time warning "cannot create
sysfs with same name" and hence a failure.

The name that is used to create sysfs entry is to be passed by the struct
led_platform_data.  Hence adding an element of type const char * and
change in lp5521 driver to use this name in creating the led device if
present else use the name obtained by I2C_BOARD_INFO.
Signed-off-by: Arun Murthy <arun.murthy@stericsson.com>
Acked-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Ilkka Koskinen <ilkka.koskinen@nokia.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>

Driver contained possibility for circular locking.

One lock is held by sysfs-core and another one by the driver itself.  This
happened when the driver created or removed sysfs entries dynamically.
There is no real need to do those operations.  Now all the sysfs entries
are created at probe and removed at removal.  Engine load sysfs entries
are now visible all the time.  However, access to the entries fails if the
engine is disabled or running.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Reviewed-by: Ilkka Koskinen <ilkka.koskinen@nokia.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>

Driver contained possibility for circular locking.

One lock is held by sysfs-core and another one by the driver itself.  This
happened when the driver created or removed sysfs entries dynamically.
There is no real need to do those operations.  Now all the sysfs entries
are created at probe and removed at removal.  Engine load and mux
configuration sysfs entries are now visible all the time.  However, access
to the entries fails if the engine is disabled or running.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Reviewed-by: Ilkka Koskinen <ilkka.koskinen@nokia.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>

Currently all leds channels begins with string lp5523.  Patch adds a
possibility to provide name via platform data.  This makes it possible to
have several chips without overlapping sysfs names.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Cc: Ilkka Koskinen <ilkka.koskinen@nokia.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>

- Remove unneeded input_free_device() after input_unregister_device().

- Add pca9532_destroy_devices() function for destroy devices.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The code doesn't check first sscanf() return value.  If first sscanf()
failed then c contains some garbage.  It might lead to reading
uninitialised stack data in the second sscanf() call.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.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>

pr_warning_ratelimited() doesn't exist.

Also include printk.h, which defines these things.

Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (39 commits)
  i915/gtt: fix ordering causing DMAR errors on object teardown.
  i915/gtt: fix ordering issues with status setup and DMAR
  drm/i915/execbuffer: Reorder binding of objects to favour restrictions
  drm/i915: If we hit OOM when allocating GTT pages, clear the aperture
  drm/i915/evict: Ensure we completely cleanup on failure
  drm/i915/execbuffer: Correctly clear the current object list upon EFAULT
  drm/i915/debugfs: Show all objects in the gtt
  drm/i915: Record AGP memory type upon error
  drm/i915: Periodically flush the active lists and requests
  drm/i915/gtt: Unmap the PCI pages after unbinding them from the GTT
  drm/i915: Record the error batchbuffer on each ring
  drm/i915: Include TLB miss overhead for computing WM
  drm/i915: Propagate error from flushing the ring
  drm/i915: detect & report PCH display error interrupts
  drm/i915: cleanup rc6 code
  drm/i915: fix rc6 enabling around suspend/resume
  drm/i915: re-enable rc6 support for Ironlake+
  drm/i915: Make the ring IMR handling private
  drm/i915/ringbuffer: Simplify the ring irq refcounting
  drm/i915/debugfs: Show the per-ring IMR
  ...

* 'tools' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
  tools: create power/x86/x86_energy_perf_policy
  tools: create power/x86/turbostat

* git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-ktest: (30 commits)
  ktest: Ask for the manditory config options instead of just failing
  ktest: Copy the last good and bad configs in config_bisect
  ktest: For grub reboot, use run_ssh instead of run_command
  ktest: Added force stop after success and failure
  ktest: Parse off the directory name in useconfig for failures
  ktest: Use different temp config name for minconfig
  ktest: Updated the sample.conf for the latest options
  ktest: Added compare script to test ktest.pl to sample.conf
  ktest: Added config_bisect test type
  ktest/cleanups: Added version 0.2, ssh as options
  ktest: Output something easy to parse for failure or success
  ktest: Allow a test case to undefine a default value
  ktest: Use $output_config instead of typing $outputdir/.config
  ktest: Write to stdout if no log file is given
  ktest: Use oldnoconfig instead of yes command
  ktest: Update the sample config file with more documentation
  ktest: New TEST_START instead of using [], and use real SHA1s
  ktest: Add poweroff after halt and powercycle after reboot
  ktest: Add POST_INSTALL to allow initrds to be created
  ktest: Added sample.conf, new %default option format
  ...

* 'stable/xenbus' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/xenbus: making backend support modular is too complex
  xen/pci: Make xen-pcifront be dependent on XEN_XENBUS_FRONTEND
  xen/xenbus: fixup checkpatch issues in xenbus_probe*
  xen/netfront: select XEN_XENBUS_FRONTEND
  xen/xenbus: clean up noise in xenbus_probe_frontend.c
  xen/xenbus: clean up noise in xenbus_probe_backend.c
  xen/xenbus: clean up noise in xenbus_probe.c
  xen/xenbus: cleanup debug noise in xenbus_comms.c
  xen/xenbus: clean up error handling
  xen/xenbus: make frontend bus GPL
  xen/xenbus: make sure backend bus is registered earlier
  xenbus/frontend: register bus earlier
  xen: remove xen/evtchn.h
  xen: add backend driver support
  xen: separate out frontend xenbus

Fix writev() to not keep writing the first segment over and over again
instead of moving onto subsequent segments and update the NTFS entry in
MAINTAINERS to reflect that Tuxera Inc. now supports the NTFS driver.
Signed-off-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MSR_IA32_ENERGY_PERF_BIAS first became available on Westmere Xeon.
It is implemented in all Sandy Bridge processors -- mobile, desktop and server.
It is expected to become increasingly important in subsequent generations.

x86_energy_perf_policy is a user-space utility to set the
hardware energy vs performance policy hint in the processor.
Most systems would benefit from "x86_energy_perf_policy normal"
at system startup, as the hardware default is maximum performance
at the expense of energy efficiency.

See x86_energy_perf_policy.8 man page for more information.

Background:

Linux-2.6.36 added "epb" to /proc/cpuinfo to indicate
if an x86 processor supports MSR_IA32_ENERGY_PERF_BIAS,
without actually modifying the MSR.

In March, 2010, Venkatesh Pallipadi proposed a small driver
that programmed MSR_IA32_ENERGY_PERF_BIAS, based on
the cpufreq governor in use.  It also offered
a boot-time cmdline option to override.
http://lkml.org/lkml/2010/3/4/457
But hiding the hardware policy behind the
governor choice was deemed "kinda icky".

In June, 2010, I proposed a generic user/kernel API to
generalize the power/performance policy trade-off.
"RFC: /sys/power/policy_preference"
http://lkml.org/lkml/2010/6/16/399
That is my preference for implementing this capability,
but I received no support on the list.

So in September, 2010, I sent x86_energy_perf_policy.c to LKML,
a user-space utility that scribbles directly to the MSR.
http://lkml.org/lkml/2010/9/28/246

Here is that same utility, after responding to some review feedback,
to live in tools/power/, where it is easily found.
Signed-off-by: Len Brown <len.brown@intel.com>

turbostat is a Linux tool to observe proper operation
of Intel(R) Turbo Boost Technology.

turbostat displays the actual processor frequency
on x86 processors that include APERF and MPERF MSRs.

Note that turbostat is of limited utility on Linux
kernels 2.6.29 and older, as acpi_cpufreq cleared
APERF/MPERF up through that release.

On Intel Core i3/i5/i7 (Nehalem) and newer processors,
turbostat also displays residency in idle power saving states,
which are necessary for diagnosing any cpuidle issues
that may have an effect on turbo-mode.

See the turbostat.8 man page for example usage.
Signed-off-by: Len Brown <len.brown@intel.com>

Previous to the last GTT rework we always rewrote the GTT then unmapped the
object, somehow this got reversed in the rework in 2.6.37-rc5 timeframe.

This fix needs to go to stable in an alternate form since the code changed.

This fixes DMAR reports on my Ironlake HP2540p.
Signed-off-by: Dave Airlie <airlied@redhat.com>

This code was setting up the status page before setting the DMAR-is-on-bit,
so we were getting DMAR errors on the status page. Reverse the two bits
of init code to the correct result.
Signed-off-by: Dave Airlie <airlied@redhat.com>

* 'drm-intel-fixes' of ssh://master.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel: (37 commits)
  drm/i915/execbuffer: Reorder binding of objects to favour restrictions
  drm/i915: If we hit OOM when allocating GTT pages, clear the aperture
  drm/i915/evict: Ensure we completely cleanup on failure
  drm/i915/execbuffer: Correctly clear the current object list upon EFAULT
  drm/i915/debugfs: Show all objects in the gtt
  drm/i915: Record AGP memory type upon error
  drm/i915: Periodically flush the active lists and requests
  drm/i915/gtt: Unmap the PCI pages after unbinding them from the GTT
  drm/i915: Record the error batchbuffer on each ring
  drm/i915: Include TLB miss overhead for computing WM
  drm/i915: Propagate error from flushing the ring
  drm/i915: detect & report PCH display error interrupts
  drm/i915: cleanup rc6 code
  drm/i915: fix rc6 enabling around suspend/resume
  drm/i915: re-enable rc6 support for Ironlake+
  drm/i915: Make the ring IMR handling private
  drm/i915/ringbuffer: Simplify the ring irq refcounting
  drm/i915/debugfs: Show the per-ring IMR
  drm/i915: Mask USER interrupts on gen6 (until required)
  drm/i915: Handle ringbuffer stalls when flushing
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (67 commits)
  cxgb4vf: recover from failure in cxgb4vf_open()
  netfilter: ebtables: make broute table work again
  netfilter: fix race in conntrack between dump_table and destroy
  ah: reload pointers to skb data after calling skb_cow_data()
  ah: update maximum truncated ICV length
  xfrm: check trunc_len in XFRMA_ALG_AUTH_TRUNC
  ehea: Increase the skb array usage
  net/fec: remove config FEC2 as it's used nowhere
  pcnet_cs: add new_id
  tcp: disallow bind() to reuse addr/port
  net/r8169: Update the function of parsing firmware
  net: ppp: use {get,put}_unaligned_be{16,32}
  CAIF: Fix IPv6 support in receive path for GPRS/3G
  arp: allow to invalidate specific ARP entries
  net_sched: factorize qdisc stats handling
  mlx4: Call alloc_etherdev to allocate RX and TX queues
  net: Add alloc_netdev_mqs function
  caif: don't set connection request param size before copying data
  cxgb4vf: fix mailbox data/control coherency domain race
  qlcnic: change module parameter permissions
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Fix bootup regression due to perf init ordering.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (72 commits)
  powerpc/pseries: Fix build of topology stuff without CONFIG_NUMA
  powerpc/pseries: Fix VPHN build errors on non-SMP systems
  powerpc/83xx: add mpc8308_p1m DMA controller device-tree node
  powerpc/83xx: add DMA controller to mpc8308 device-tree node
  powerpc/512x: try to free dma descriptors in case of allocation failure
  powerpc/512x: add MPC8308 dma support
  powerpc/512x: fix the hanged dma transfer issue
  powerpc/512x: scatter/gather dma fix
  powerpc/powermac: Make auto-loading of therm_pm72 possible
  of/address: Use propper endianess in get_flags
  powerpc/pci: Use printf extension %pR for struct resource
  powerpc: Remove unnecessary casts of void ptr
  powerpc: Disable VPHN polling during a suspend operation
  powerpc/pseries: Poll VPA for topology changes and update NUMA maps
  powerpc: iommu: Add device name to iommu error printks
  powerpc: Record vma->phys_addr in ioremap()
  powerpc: Update compat_arch_ptrace
  powerpc: Fix PPC_PTRACE_SETHWDEBUG on PPC_BOOK3S
  powerpc/time: printk time stamp init not correct
  powerpc: Minor cleanups for machdep.h
  ...