These recent percpu commits:

  2485b646: x86,percpu: Move out of place 64 bit ops into X86_64 section
  8270137a: cpuops: Use cmpxchg for xchg to avoid lock semantics

Caused this 'perf top' crash:

 Kernel panic - not syncing: Fatal exception in interrupt
 Pid: 0, comm: swapper Tainted: G     D
 2.6.38-rc2-00181-gef71723 #413 Call Trace: <IRQ> [<ffffffff810465b5>]
    ? panic
    ? kmsg_dump
    ? kmsg_dump
    ? oops_end
    ? no_context
    ? __bad_area_nosemaphore
    ? perf_output_begin
    ? bad_area_nosemaphore
    ? do_page_fault
    ? __task_pid_nr_ns
    ? perf_event_tid
    ? __perf_event_header__init_id
    ? validate_chain
    ? perf_output_sample
    ? trace_hardirqs_off
    ? page_fault
    ? irq_work_run
    ? update_process_times
    ? tick_sched_timer
    ? tick_sched_timer
    ? __run_hrtimer
    ? hrtimer_interrupt
    ? account_system_vtime
    ? smp_apic_timer_interrupt
    ? apic_timer_interrupt
 ...

Looking at assembly code, I found:

list = this_cpu_xchg(irq_work_list, NULL);

gives this wrong code : (gcc-4.1.2 cross compiler)

ffffffff810bc45e:
	mov    %gs:0xead0,%rax
	cmpxchg %rax,%gs:0xead0
	jne    ffffffff810bc45e <irq_work_run+0x3e>
	test   %rax,%rax
	je     ffffffff810bc4aa <irq_work_run+0x8a>

Tell gcc we dirty eax/rax register in percpu_xchg_op()

Compiler must use another register to store pxo_new__

We also dont need to reload percpu value after a jump,
since a 'failed' cmpxchg already updated eax/rax

Wrong generated code was :
	xor     %rax,%rax   /* load 0 into %rax */
1:	mov     %gs:0xead0,%rax
	cmpxchg %rax,%gs:0xead0
	jne     1b
	test    %rax,%rax

After patch :

	xor     %rdx,%rdx   /* load 0 into %rdx */
	mov     %gs:0xead0,%rax
1:	cmpxchg %rdx,%gs:0xead0
	jne     1b:
	test    %rax,%rax
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <1295973114.3588.312.camel@edumazet-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Left-over from the x86 merge ...
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D3E23D1.7010405@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

In arch/x86/kernel/dumpstack_64.c::dump_trace() we have this code:

...
  		if (!stack) {
  			unsigned long dummy;
  			stack = &dummy;
  			if (task && task != current)
  				stack = (unsigned long *)task->thread.sp;
  		}

  		bp = stack_frame(task, regs);
  		/*
  		 * Print function call entries in all stacks, starting at the
  		 * current stack address. If the stacks consist of nested
  		 * exceptions
  		 */
  		tinfo = task_thread_info(task);

  		for (;;) {
  			char *id;
  			unsigned long *estack_end;
  			estack_end = in_exception_stack(cpu, (unsigned long)stack,
  							&used, &id);
...

You'll notice that we assign to 'stack' the address of the variable
'dummy' which is only in-scope inside the 'if (!stack)'. So when we later
access stack (at the end of the above, and assuming we did not take the
'if (task && task != current)' branch) we'll be using the address of a
variable that is no longer in scope. I believe this patch is the proper
fix, but I freely admit that I'm not 100% certain.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
LKML-Reference: <alpine.LNX.2.00.1101242232590.10252@swampdragon.chaosbits.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Fix a shutdown regression caused by 2a2d31c8 ("intel_idle: open
broadcast clock event").  The clockevent framework can automatically
shutdown broadcast timers for hotremove CPUs.  And we get a shutdown
regression when we shutdown broadcast timer for hot remove CPU, so just
delete some code.

Also fix some section mismatch.
Reported-by: Ari Savolainen <ari.m.savolainen@gmail.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  omap: DMA: clear interrupt status correctly
  OMAP3: Devkit8000: Fix tps65930 pullup/pulldown configuration
  arm: omap3: cm-t3517: minor comment fix
  arm: omap3: cm-t3517: rtc fix
  omap1: Fix sched_clock implementation when both MPU timer and 32K timer are used
  omap1: Fix booting for 15xx and 730 with omap1_defconfig
  omap1: Fix sched_clock for the MPU timer
  OMAP: PRCM: remove duplicated headers
  OMAP4: clockdomain: bypass unimplemented wake-up dependency functions on OMAP4
  OMAP: counter_32k: init clocksource as part of machine timer init

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf tools: Fix time function double declaration with glibc
  perf tools: Fix build by checking if extra warnings are supported
  perf tools: Fix build when using gcc 3.4.6
  perf tools: Add missing header, fixes build
  perf tools: Fix 64 bit integer format strings
  perf test: Fix build on older glibcs
  perf: perf_event_exit_task_context: s/rcu_dereference/rcu_dereference_raw/
  perf test: Use cpu_map->[cpu] when setting affinity
  perf symbols: Fix annotation of thumb code
  perf: Annotate cpuctx->ctx.mutex to avoid a lockdep splat
  powerpc, perf: Fix frequency calculation for overflowing counters (FSL version)
  perf: Fix perf_event_init_task()/perf_event_free_task() interaction
  perf: Fix find_get_context() vs perf_event_exit_task() race

Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  RTC: Remove Kconfig symbol for UIE emulation
  RTC: Properly handle rtc_read_alarm error propagation and fix bug
  RTC: Propagate error handling via rtc_timer_enqueue properly
  acpi_pm: Clear pmtmr_ioport if acpi_pm initialization fails
  rtc: Cleanup removed UIE emulation declaration
  hrtimers: Notify hrtimer users of switches to NOHZ mode

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix poor interactivity on UP systems due to group scheduler nice tune bug

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix jump label with RO/NX module protection crash
  x86, hotplug: Fix powersavings with offlined cores on AMD
  x86, mcheck, therm_throt.c: Export symbol platform_thermal_notify to allow coretemp to handler intr
  x86: Use asm-generic/cacheflush.h
  x86: Update CPU cache attributes table descriptors

Michael Witten and Christian Kujau reported that the autogroup
scheduling feature hurts interactivity on their UP systems.

It turns out that this is an older bug in the group scheduling code,
and the wider appeal provided by the autogroup feature exposed it
more prominently.

When on UP with FAIR_GROUP_SCHED enabled, tune shares
only affect tg->shares, but is not reflected in
tg->se->load. The reason is that update_cfs_shares()
does nothing on UP.

So introduce update_cfs_shares() for UP && FAIR_GROUP_SCHED.

This issue was found when enable autogroup scheduling was enabled,
but it is an older bug that also exists on cgroup.cpu on UP.
Reported-and-Tested-by: Michael Witten <mfwitten@gmail.com>
Reported-and-Tested-by: Christian Kujau <christian@nerdbynature.de>
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110124073352.GA24186@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* 'BUG_ON' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  Remove MAYBE_BUILD_BUG_ON
  BUILD_BUG_ON: make it handle more cases

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: fix missing semicolons in MODULE macro usage
  param: add null statement to compiled-in module params
  module: fix linker error for MODULE_VERSION when !MODULE and CONFIG_SYSFS=n
  module: show version information for built-in modules in sysfs

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  selinux: return -ENOMEM when memory allocation fails
  tpm: fix panic caused by "tpm: Autodetect itpm devices"
  TPM: Long default timeout fix
  trusted keys: Fix a memory leak in trusted_update().
  keys: add trusted and encrypted maintainers
  encrypted-keys: rename encrypted_defined files to encrypted
  trusted-keys: rename trusted_defined files to trusted

Now BUILD_BUG_ON() can handle optimizable constants, we don't need
MAYBE_BUILD_BUG_ON any more.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

BUILD_BUG_ON used to use the optimizer to do code elimination or fail
at link time; it was changed to first the size of a negative array (a
nicer compile time error), then (in
8c87df45) to a bitfield.

This forced us to change some non-constant cases to MAYBE_BUILD_BUG_ON();
as Jan points out in that commit, it didn't work as intended anyway.

bitfields: needs a literal constant at parse time, and can't be put under
	"if (__builtin_constant_p(x))" for example.
negative array: can handle anything, but if the compiler can't tell it's
	a constant, silently has no effect.
link time: breaks link if the compiler can't determine the value, but the
	linker output is not usually as informative as a compiler error.

If we use the negative-array-size method *and* the link time trick,
we get the ability to use BUILD_BUG_ON() under __builtin_constant_p()
branches, and maximal ability for the compiler to detect errors at
build time.

We also document it thoroughly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jan Beulich <JBeulich@novell.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>

You always needed them when you were a module, but the builtin versions
of the macros used to be more lenient.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Add an unused struct declaration statement requiring a
terminating semicolon to the compile-in case to provoke an
error if __MODULE_INFO() is used without the terminating
semicolon. Previously MODULE_ALIAS("foo") (no semicolon)
compiled fine if MODULE was not selected.

Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lib/built-in.o:(__modver+0x8): undefined reference to `__modver_version_show'
lib/built-in.o:(__modver+0x2c): undefined reference to `__modver_version_show'

Simplest to just not emit anything: if they've disabled SYSFS they probably
want the smallest kernel possible.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Currently only drivers that are built as modules have their versions
shown in /sys/module/<module_name>/version, but this information might
also be useful for built-in drivers as well. This especially important
for drivers that do not define any parameters - such drivers, if
built-in, are completely invisible from userspace.

This patch changes MODULE_VERSION() macro so that in case when we are
compiling built-in module, version information is stored in a separate
section. Kernel then uses this data to create 'version' sysfs attribute
in the same fashion it creates attributes for module parameters.
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Return -ENOMEM when memory allocation fails in cond_init_bool_indexes,
correctly propagating error code to caller.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: James Morris <jmorris@namei.org>

commit 3f0d3d01 adds a check for
PNP device id to the common tpm_tis_init() function, which in some
cases (force=1) will be called without the device being a member of
a pnp_dev. Oopsing and panics ensue.

Move the test up to before the call to tpm_tis_init(), since it
just modifies a global variable anyway.
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

If duration variable value is 0 at this point, it's because
chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
This patch sets then the lowest timeout just to give enough
time for tpm_get_timeouts() to further succeed.

This fix avoids long boot times in case another entity attempts
to send commands to the TPM when the TPM isn't accessible.
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

One failure path in security/keys/trusted.c::trusted_update() does
not free 'new_p' while the others do. This patch makes sure we also free
it in the remaining path (if datablob_parse() returns different from
Opt_update).
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: James Morris <jmorris@namei.org>

Add myself and David Safford as maintainers for trusted/encrypted keys.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

Rename encrypted_defined.c and encrypted_defined.h files to encrypted.c and
encrypted.h, respectively. Based on request from David Howells.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

Rename trusted_defined.c and trusted_defined.h files to trusted.c and
trusted.h, respectively. Based on request from David Howells.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

If we use jump table in module init, there are marked
as removed in __jump_table section after init is done.

But we already applied ro permissions on the module, so
we can't modify a read only section (crash in
remove_jump_label_module_init).

Make the __jump_table section rw.
Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Xiaotian Feng <xtfeng@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: Xuxian Jiang <jiang@cs.ncsu.edu>
Cc: James Morris <jmorris@namei.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dave Jones <davej@redhat.com>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4D3C3F20.7030203@free.fr>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Fix new fs/dcache.c kernel-doc warnings:

  Warning(fs/dcache.c:184): No description found for parameter 'dentry'
  Warning(fs/dcache.c:296): No description found for parameter 'parent'
  Warning(fs/dcache.c:1985): No description found for parameter 'dparent'
  Warning(fs/dcache.c:1985): Excess function parameter 'parent' description in 'd_validate'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Alexander Viro <viro@zeniv.linux.org.uk>
Cc:	Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new rapidio kernel-doc warnings:

  Warning(drivers/rapidio/rio-scan.c:953): No description found for parameter 'prev'
  Warning(drivers/rapidio/rio-scan.c:953): No description found for parameter 'prev_port'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix move of drivers/serial/ to drivers/tty/, where it broke
one of the docbook files:

  docproc: drivers/serial/serial_core.c: No such file or directory
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

It's enough to include the local "debug.h" file to trigger it.

man time reveals this is already declared in glibc:

time - get time in seconds
-> rename the variable.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: arjan@infradead.org
LPU-Reference: <1295620209-13859-2-git-send-email-trenn@suse.de>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The -Wstack-protector and -Wvolatile-register-var warnings, for
instance, are not supported by gcc 3.4.6.

So fix by doing the same check we already do for -fstack-protector-all.

With this and the other patches in this series, perf builds unmodified
on, for instance, RHEL4.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

[acme@localhost linux]$ make O=~acme/git/build/perf -C tools/perf
make: Entering directory `/home/acme/git/linux/tools/perf'
Makefile:526: No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev
Makefile:582: newt not found, disables TUI support. Please install newt-devel or libnewt-dev
    CC /home/acme/git/build/perf/builtin-annotate.o
In file included from builtin-annotate.c:23:
util/parse-events.h:26: warning: declaration of 'evsel_list' shadows a global declaration
util/parse-events.h:12: warning: shadowed declaration is here
make: *** [/home/acme/git/build/perf/builtin-annotate.o] Error 1
make: Leaving directory `/home/acme/git/linux/tools/perf'
[acme@localhost linux]$ gcc --version | head -1
gcc (GCC) 3.4.6 20060404 (Red Hat 3.4.6-11)
[acme@localhost linux]$

Fix it by renaming the parameter to evlist.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We need the definiton for __always_inline in bitops.h to fix the build
on distros where it isn't available or compiler.h doesn't get included
indirectly.

One of the fixes needed to build perf on RHEL4 systems, for instance.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Using %L[uxd] has issues in some architectures, like on ppc64.  Fix it
by making our 64 bit integers typedefs of stdint.h types and using
PRI[ux]64 like, for instance, git does.

Reported by Denis Kirjanov that provided a patch for one case, I went
and changed all cases.
Reported-by: Denis Kirjanov <dkirjanov@kernel.org>
Tested-by: Denis Kirjanov <dkirjanov@kernel.org>
LKML-Reference: <20110120093246.GA8031@hera.kernel.org>
Cc: Denis Kirjanov <dkirjanov@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pingtian Han <phan@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Where we don't have CPU_ALLOC & friends. As the tools are being used in older
distros where the only allowed change are to replace the kernel, like RHEL4 and
5.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/urgent

ea530692 made a CPU use monitor/mwait
when offline. This is not the optimal choice for AMD wrt to powersavings
and we'd prefer our cores to halt (i.e. enter C1) instead. For this, the
same selection whether to use monitor/mwait has to be used as when we
select the idle routine for the machine.

With this patch, offlining cores 1-5 on a X6 machine allows core0 to
boost again.

[ hpa: putting this in urgent since it is a (power) regression fix ]
Reported-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: stable@kernel.org # 37.x
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.hl>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <1295534572-10730-1-git-send-email-bp@amd64.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

* 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (101 commits)
  [media] staging/lirc: fix mem leaks and ptr err usage
  [media] hdpvr: reduce latency of i2c read/write w/recycled buffer
  [media] hdpvr: enable IR part
  [media] rc/mceusb: timeout should be in ns, not us
  [media] v4l2-device: fix 'use-after-freed' oops
  [media] v4l2-dev: don't memset video_device.dev
  [media] zoran: use video_device_alloc instead of kmalloc
  [media] w9966: zero device state after a detach
  [media] v4l: Fix a use-before-set in the control framework
  [media] v4l: Include linux/videodev2.h in media/v4l2-ctrls.h
  [media] DocBook/v4l: update V4L2 revision and update copyright years
  [media] DocBook/v4l: fix validation error in dev-rds.xml
  [media] v4l2-ctrls: queryctrl shouldn't attempt to replace V4L2_CID_PRIVATE_BASE IDs
  [media] v4l2-ctrls: fix missing 'read-only' check
  [media] pvrusb2: Provide more information about IR units to lirc_zilog and ir-kbd-i2c
  [media] ir-kbd-i2c: Add back defaults setting for Zilog Z8's at addr 0x71
  [media] lirc_zilog: Update TODO.lirc_zilog
  [media] lirc_zilog: Add Andy Walls to copyright notice and authors list
  [media] lirc_zilog: Remove useless struct i2c_driver.command function
  [media] lirc_zilog: Remove unneeded tests for existence of the IR Tx function
  ...