drivers: cpufreq: Send a uevent when governor changes

 * Useful so userspace tools can reconfigure.

Change-Id: Ib423910b8b9ac791ebe81a75bf399f58272f64f2
cpufreq: Fix broken uevents for cpufreq governor and cpu devices

cyanogens uevent commit when the governor changes was rendered
non-working since kitkat (or so) as the uevent filter function
caused events to be dropped. Now hook into cpufreq_core_init()
and cpufreq_add_dev_interface() to create our basic ksets for
cpufreq and cpu devices. Also, we don't need to set environmental
data, so clean it up a bit.

This commit requires a change in ueventd.rc that add rules for
several files of interest.

Change-Id: I3aafa0d4e18363e1d68535f513099ecd27024007
sched/debug: Make sysrq prints of sched debug data optional

Calls to sysrq_sched_debug_show() can yield rather verbose output
which contributes to log spew and, under heavy load, may increase
the chances of a watchdog bark.

Make printing of this data optional with the introduction of a
new Kconfig, CONFIG_SYSRQ_SCHED_DEBUG.

Change-Id: I5f54d901d0dea403109f7ac33b8881d967a899ed
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
sched,cgroup: Fix up task_groups list

With multiple instances of task_groups, for_each_rt_rq() is a noop,
no task groups having been added to the rt.c list instance.  This
renders __enable/disable_runtime() and print_rt_stats() noop, the
user (non) visible effect being that rt task groups are missing in
/proc/sched_debug.

Change-Id: Ib337ebda0e752f838d787c03fe1b0a8f03ea0551
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: stable@kernel.org # v3.3+
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1344308413.6846.7.camel@marge.simpson.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: 35cf4e50b16331def6cfcbee11e49270b6db07f5
Git-repo: git://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
sched: convert WARN_ON() to printk_sched() in try_to_wake_up_local()

try_to_wake_up_local() is called with the rq lock held. Printing to
console in this context can result in a deadlock if klogd needs to
be woken up. Print to the kernel log buffer via printk_sched()
instead which avoids the wakeup.

Change-Id: Ia07baea3cb7e0b158545207fdbbb866203256d3c
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
sched/rt: Use root_domain of rt_rq not current processor

When the system has multiple domains do_sched_rt_period_timer()
can run on any CPU and may iterate over all rt_rq in
cpu_online_mask.  This means when balance_runtime() is run for a
given rt_rq that rt_rq may be in a different rd than the current
processor.  Thus if we use smp_processor_id() to get rd in
do_balance_runtime() we may borrow runtime from a rt_rq that is
not part of our rd.

This changes do_balance_runtime to get the rd from the passed in
rt_rq ensuring that we borrow runtime only from the correct rd
for the given rt_rq.

This fixes a BUG at kernel/sched/rt.c:687! in __disable_runtime
when we try reclaim runtime lent to other rt_rq but runtime has
been lent to a rt_rq in another rd.

Change-Id: Id8b9f88bdd783ef87bfa8d288a2fe7e86dd0b1e2
Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Mike Galbraith <bitbucket@online.de>
Cc: peterz@infradead.org
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1358186131-29494-1-git-send-email-sbohrer@rgmadvisors.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Git-commit: 89960feebaf4f9a53f93a0ce6888207e4a808799
Git-repo: git://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
CHROMIUM: mm: Fix calculation of dirtyable memory

The system uses global_dirtyable_memory() to calculate
number of dirtyable pages/pages that can be allocated
to the page cache.  A bug causes an underflow thus making
the page count look like a big unsigned number.  This in turn
confuses the dirty writeback throttling to aggressively write
back pages as they become dirty (usually 1 page at a time).

Fix is to ensure there is no underflow while doing the math.

Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Signed-off-by: Puneet Kumar <puneetster@chromium.org>

BUG=chrome-os-partner:16011
TEST=Manual; boot kernel, powerwash, login with testaccount and
make sure no jank occurs on sync of applications

Change-Id: I614e7c3156e014f0f28a4ef9bdd8cb8a2cd07b2a
Reviewed-on: https://gerrit.chromium.org/gerrit/37612
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Commit-Ready: Puneet Kumar <puneetster@chromium.org>
Reviewed-by: Puneet Kumar <puneetster@chromium.org>
Tested-by: Puneet Kumar <puneetster@chromium.org>
ARM: 7430/1: sizes.h: move from asm-generic to <linux/sizes.h>

sizes.h is used throughout the AMBA code and drivers, so the header
should be available to everyone in order to driver AMBA/PrimeCell
peripherals behind a PCI bridge where the host can be any platform
(I'm doing it under x86).

At this step <asm-generic/sizes.h> includes <linux/sizes.h>,
to allow a grace period for both in-tree and out-of-tree drivers.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7432/1: use the new linux/sizes.h

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: Speed up page list initialization during boot

During boot, we populate the page lists by using the page freeing
mechanism on every individual page.  Unfortunately, this is very
inefficient because the memory manager spends a lot of time coalescing
pairs of adjacent free pages into bigger blocks.

Rather than adding a single page at a time, we can take advantage of the
fact that we know that all the pages are available and free up big
blocks of pages at a time instead.

This reduces boot time by 260ms on pit and 560ms on pi.

BUG=chrome-os-partner:25476
TEST=platform_BootPerf

Change-Id: Ib12bf17b66f18677b41d215e527aa0cd2e1f60be
Signed-off-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/188971
Reviewed-by: Sonny Rao <sonnyrao@chromium.org>
Commit-Queue: Doug Anderson <dianders@chromium.org>
ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork

Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to
prevent it from being used as a covert channel between two tasks.

There are more and more applications coming to Windows RT,
Wine could support them, but mostly they expect to have
the thread environment block (TEB) in TPIDRURW.

This patch preserves that register per thread instead of clearing it.
Unlike the TPIDRURO, which is already switched, the TPIDRURW
can be updated from userspace so needs careful treatment in the case that we
modify TPIDRURW and call fork(). To avoid this we must always read
TPIDRURW in copy_thread.

Change-Id: Ib1e25be7b9faa846ba5335aad2574e21a1246066
Signed-off-by: André Hentschel <nerv@dawncrow.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: a4780adeefd042482f624f5e0d577bf9cdcbb760
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: fixed merge conflict]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: poison the vectors page

Fill the empty regions of the vectors page with an exception generating
instruction.  This ensures that any inappropriate branch to the vector
page is appropriately trapped, rather than just encountering some code
to execute.  (The vectors page was filled with zero before, which
corresponds with the "andeq r0, r0, r0" instruction - a no-op.)

Change-Id: I74c0105a2bcb3b78d9fc8b105a05c0fc269ba400
Cc: <stable@vger.kernel.org>
Acked-by Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: f928d4f2a86f46b030fa0850385b4391fc2b5918
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: poison memory between kuser helpers

Poison the memory between each kuser helper.  This ensures that any
branch between the kuser helpers will be appropriately trapped.

Change-Id: Ifa4abe51d3dd89a96670a8609cd472fa03988e7e
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: 5b43e7a383d69381ffe53423e46dd0fafae07da3
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: move vector stubs

Move the machine vector stubs into the page above the vector page,
which we can prevent from being visible to userspace.  Also move
the reset stub, and place the swi vector at a location that the
'ldr' can get to it.

This hides pointers into the kernel which could give valuable
information to attackers, and reduces the number of exploitable
instructions at a fixed address.

Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: 19accfd373847ac3d10623c5d20f948846299741
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

ARM: use linker magic for vectors and vector stubs

Use linker magic to create the vectors and vector stubs: we can tell the
linker to place them at an appropriate VMA, but keep the LMA within the
kernel.  This gets rid of some unnecessary symbol manipulation, and
have the linker calculate the relocations appropriately.

Change-Id: I694f6b651e60fccd7e3c818f981a3883f9c212de
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: b9b32bf70f2fb710b07c94e13afbc729afe221da
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: squashed 19accfd and b9b32bf because 19accfd
			broke build]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: fiq: change FIQ_START to a variable

The commit a2be01b (ARM: only include mach/irqs.h for !SPARSE_IRQ)
makes mach/irqs.h only be included for !SPARSE_IRQ build.  There are
a nubmer of platforms have FIQ_START defined in mach/irqs.h for FIQ
support.

  arch/arm/mach-rpc/include/mach/irqs.h:#define FIQ_START         64
  arch/arm/mach-s3c24xx/include/mach/irqs.h:#define FIQ_START             IRQ_EINT0
  arch/arm/plat-mxc/include/mach/irqs.h:#define FIQ_START 0

If SPARSE_IRQ is enabled for any of these platforms, the following
compile error will be seen.

  arch/arm/kernel/fiq.c: In function ‘enable_fiq’:
  arch/arm/kernel/fiq.c:127:19: error: ‘FIQ_START’ undeclared (first use in this function)
  arch/arm/kernel/fiq.c:127:19: note: each undeclared identifier is reported only once for each function it appears in
  arch/arm/kernel/fiq.c: In function ‘disable_fiq’:
  arch/arm/kernel/fiq.c:132:20: error: ‘FIQ_START’ undeclared (first use in this function)

The patch changes fiq code to have init_FIQ take FIQ_START from
platforms as a parameter and assign it to variable fiq_start which
is to replace FIQ_START uses in enable_fiq/disable_fiq.

Change-Id: I9bf8de403d06fec7597fd4652c78079fd4fa981b
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: bc89663aa5c7ca620f58c34ab531ca409119becc
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: update FIQ support for relocation of vectors

FIQ should no longer copy the FIQ code into the user visible vector
page.  Instead, it should use the hidden page.  This change makes
that happen.

Change-Id: Iec7716c43e2377fa3d66cc36ff8d141f58bfb6bf
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: e39e3f3ebfef03450cf7bfa7a974a8c61f7980c8
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: fixed merge conflict]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: allow kuser helpers to be removed from the vector page

Provide a kernel configuration option to allow the kernel user helpers
to be removed from the vector page, thereby preventing their use with
ROP (return orientated programming) attacks.  This option is only
visible for CPU architectures which natively support all the operations
which kernel user helpers would normally provide, and must be enabled
with caution.

Change-Id: Ic118b6951f4abca53ceb22b5a768ddad2ceb22b6
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: f6f91b0d9fd971c630cef908dde8fe8795aefbf8
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: fixed merge conflict]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: move signal handlers into a vdso-like page

Move the signal handlers into a VDSO page rather than keeping them in
the vectors page.  This allows us to place them randomly within this
page, and also map the page at a random location within userspace
further protecting these code fragments from ROP attacks.  The new
VDSO page is also poisoned in the same way as the vector page.

Change-Id: Ic45bb26efb1f00de0a025d36fc15dbd6580dc7de
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: 48be69a026b2c17350a5ef18a1959a919f60be7d
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: fixed merge conflict]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: make vectors page inaccessible from userspace

If kuser helpers are not provided by the kernel, disable user access to
the vectors page.  With the kuser helpers gone, there is no reason for
this page to be visible to userspace.

Change-Id: Ia00a34e7952552634ccb03ee038cf3d0ead88459
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: a5463cd3435475386cbbe7b06e01292ac169d36f
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[joonwoop@codeaurora.org: fixed merge conflict]
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
ARM: fix a cockup in 48be69a02 (ARM: move signal handlers into a vdso-like page)

Unfortunately, I never committed the fix to a nasty oops which can
occur as a result of that commit:

------------[ cut here ]------------
kernel BUG at /home/olof/work/batch/include/linux/mm.h:414!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 490 Comm: killall5 Not tainted 3.11.0-rc3-00288-gabe0308 #53
task: e90acac0 ti: e9be8000 task.ti: e9be8000
PC is at special_mapping_fault+0xa4/0xc4
LR is at __do_fault+0x68/0x48c

This doesn't show up unless you do quite a bit of testing; a simple
boot test does not do this, so all my nightly tests were passing fine.

The reason for this is that install_special_mapping() expects the
page array to stick around, and as this was only inserting one page
which was stored on the kernel stack, that's why this was blowing up.

Change-Id: Ib2cf8c19833e17d8d145e29141d68aaefd4dc233
Reported-by: Olof Johansson <olof@lixom.net>
Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Git-commit: e0d407564b532d978b03ceccebd224a05d02f111
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
CRs-fixed: 561044
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>