commit a1531acd43310a7e4571d52e8846640667f4c74b upstream

Ingo Molnar provided a fix to not call _PPC at processor driver
initialization time in "[PATCH] ACPI: fix cpufreq regression" (git
commit e4233dec749a3519069d9390561b5636a75c7579)

But it can still happen that _PPC is called at processor driver
initialization time.

This patch should make sure that this is not possible anymore.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

commit 326f6a5c9c9e1a62aec37bdc0c3f8d53adabe77b upstream

Format string bug.  Not exploitable, as this is only writable by root,
but worth fixing all the same.

From: Chris Wright <chrisw@sous-sol.org>
Spotted-by: Ilja van Sprundel <ilja@netric.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

upstream commit: 879000f94442860e72c934f9e568989bc7fb8ec4

If cpu specific cpufreq driver(i.e.  longrun) has "setpolicy" function,
governor object isn't set into cpufreq_policy object at "__cpufreq_set_policy"
function in driver/cpufreq/cpufreq.c .

This causes a null object access at "store_scaling_setspeed" and
"show_scaling_setspeed" function in driver/cpufreq/cpufreq.c when reading or
writing through /sys interface (ex.  cat
/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed)

Addresses:
	http://bugzilla.kernel.org/show_bug.cgi?id=10654
	https://bugzilla.redhat.com/show_bug.cgi?id=443354

Signed-off-by: CHIKAMA Masaki <masaki.chikama@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

Fix the following warnings:
WARNING: vmlinux.o(.text+0xfe6711): Section mismatch in reference from the function cpufreq_unregister_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.text+0xfe68af): Section mismatch in reference from the function cpufreq_register_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.exit.text+0xc4fa): Section mismatch in reference from the function cpufreq_stats_exit() to the variable .cpuinit.data:cpufreq_stat_cpu_notifier

The warnings were casued by references to unregister_hotcpu_notifier()
from normal functions or exit functions.
This is flagged by modpost as a potential error because
it does not know that for the non HOTPLUG_CPU
scenario the unregister_hotcpu_notifier() is a nop.
Silence the warning by replacing the __initdata
annotation with a __refdata annotation.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>

refactor to use gotos instead of explicit exit paths

Signed-off-by: Dave Jones <davej@redhat.com>

refactor to use gotos instead of explicit exit paths

Signed-off-by: Dave Jones <davej@redhat.com>

The cpufreq core should not take an extra kobject reference count for no
reason, and then refuse to release it.  This has been reported as
keeping machines from properly powering down all the way.


Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Yi Yang <yi.y.yang@intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Frans Pop <elendil@planet.nl>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

cpufreq support can't be built as a module. Fix the related configuration
help message.

Signed-off-by: Stefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: Dave Jones <davej@redhat.com>

Eliminate cpufreq_userspace scaling_setspeed deadlock.

Luming Yu recently uncovered yet another cpufreq related deadlock.
One thread that continuously switches the governors and the other thread that
repeatedly cats the contents of cpufreq directory causes both these threads to
go into a deadlock.

Detailed examination of the deadlock showed the exact flow before the deadlock
as:

Thread 1			Thread 2
________			________
				cats files under /sys/devices/.../cpufreq/
Set governor to userspace
  Adds a new sysfs entry for
  scaling_setspeed
				cats files under /sys/devices/.../cpufreq/

Set governor to performance
  Holds cpufreq_rw_sem in write
  mode
  Sends a STOP notify to
  userspace governor
				cat /sys/devices/.../cpufreq/scaling_setspeed
				  Gets a handle on the above sysfs entry with
				  sysfs_get_active
				  Blocks while trying to get cpufreq_rw_sem
				  in read mode
  Remove a sysfs entry for
  scaling_setspeed
    Blocks on sysfs_deactivate
    while waiting for earlier
    get_active (on other thread)
    to drain

At this point both threads go into deadlock and any other thread that tries to
do anything with sysfs cpufreq will also block.

There seems to be no easy way to avoid this deadlock as long as
cpufreq_userspace adds/removes the sysfs entry under same kobject as cpufreq.
Below patch moves scaling_setspeed to cpufreq.c, keeping it always and calling
back the governor on read/write. This is the cleanest fix I could think of,
even though adding two callbacks in governor structure just for this seems
unnecessary.

Note that the change makes scaling_setspeed under /sys/.../cpufreq permanent
and returns <unsupported> when governor is not userspace.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>

In freq_table.c, show_available_freqs()'s comment is oberviously wrong.
Change the comment to a new one to avoid confusion.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>