msm: mdss: Handle null panel name configuration

LK sends default panel parameter string through
kernel command line argument if auto detection
fails or display is not enabled. DSI driver probe
is failing to parse this panel parameter passed by
LK. With this change, DSI driver will select the
preferred primary panel configured in dtsi if
it parsing fails.

Change-Id: Ief4804ae2cc10abf74317d64fb1b889bd41228d2
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>

Conflicts:
	drivers/video/msm/mdss/mdss_dsi.c
ARM: decompressor: Enable unaligned memory access for v6 and above

Modern GCC can generate code which makes use of the CPU's native
unaligned memory access capabilities.  This is useful for the C
decompressor implementations used for unpacking compressed kernels.

This patch disables alignment faults and enables the v6 unaligned
access model on CPUs which support these features (i.e., v6 and
later), allowing full unaligned access support for C code in the
decompressor.

The decompressor C code must not be built to assume that unaligned
access works if support for v5 or older platforms is included in
the kernel.

For correct code generation, C decompressor code must always use
the get_unaligned and put_unaligned accessors when dealing with
unaligned pointers, regardless of this patch.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
mm/page_alloc: fix the page address of higher page's buddy calculation

commit 0ba8f2d59304dfe69b59c034de723ad80f7ab9ac upstream.

The heuristic method for buddy has been introduced since commit
43506fad21ca ("mm/page_alloc.c: simplify calculation of combined index
of adjacent buddy lists").  But the page address of higher page's buddy
was wrongly calculated, which will lead page_is_buddy to fail for ever.
IOW, the heuristic method would be disabled with the wrong page address
of higher page's buddy.

Calculating the page address of higher page's buddy should be based
higher_page with the offset between index of higher page and index of
higher page's buddy.

Signed-off-by: Haifeng Li <omycle@gmail.com>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: KyongHo Cho <pullip.cho@samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.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@linuxfoundation.org>
hrtimer:__run_hrtimer races with enqueue_hrtimer

We hit a kernel panic at __run_hrtimer=>BUG_ON(timer->state != HRTIMER_STATE_CALLBACK).
<2>[   10.226053, 3] kernel BUG at /home/android/xiaobing/ymz/r4/hardware/intel/linux-2.6/kernel/hrtimer.c:1228!
<0>[   10.235682, 3] invalid opcode: 0000 [#1] PREEMPT SMP
<4>[   10.240716, 3] Modules linked in: wl12xx_sdio wl12xx mac80211 cfg80211 compat btwilink rmi4(C) fmdrv_chr st_drv matrix(C)
<4>[   10.251651, 3]
<4>[   10.253391, 3] Pid: 68, comm: kworker/3:4 Tainted: G        WC  3.0.34-140430-g2af538d #45 Intel Corporation CloverTrail/FFRD
<4>[   10.264674, 3] EIP: 0060:[<c126c7ed>] EFLAGS: 00010002 CPU: 3
<4>[   10.270411, 3] EIP is at __run_hrtimer+0xbd/0x240
<4>[   10.275091, 3] EAX: 00000001 EBX: f67fb6b8 ECX: f57b4000 EDX: 00007301
<4>[   10.281602, 3] ESI: c1d614c0 EDI: f67fb680 EBP: f57b5dd8 ESP: f57b5da8
<4>[   10.288113, 3]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
<0>[   10.293754, 3] Process kworker/3:4 (pid: 68, ti=f57b4000 task=f57aa730 task.ti=f57b4000)
<0>[   10.301827, 3] Stack:
<4>[   10.304083, 3]  00000000 c1afef40 f57b5dd8 c167a6e0 f67fb680 20b366e3 f67fb6b8 f57b5e14
<4>[   10.312069, 3]  00000001 f67fb6b8 00000001 f67fb680 f57b5e28 c126d1e5 f57b5e08 c126f325
<4>[   10.320055, 3]  00000000 86b9868d 00000001 86b9868d 00000001 00000003 ffffffff 7fffffff
<0>[   10.328041, 3] Call Trace:
<4>[   10.330742, 3]  [<c167a6e0>] ? gburst_thread_stop.isra.25+0x40/0x40
<4>[   10.336988, 3]  [<c126d1e5>] hrtimer_interrupt+0xd5/0x250
<4>[   10.342368, 3]  [<c126f325>] ? sched_clock_cpu+0xe5/0x150
<4>[   10.347753, 3]  [<c1871d44>] smp_apic_timer_interrupt+0x54/0x88
<4>[   10.353654, 3]  [<c1496558>] ? trace_hardirqs_off_thunk+0xc/0x14
<4>[   10.359643, 3]  [<c186be9f>] apic_timer_interrupt+0x2f/0x34
<4>[   10.365199, 3]  [<c186e60f>] ? sub_preempt_count+0x1f/0x50
<4>[   10.370669, 3]  [<c149558a>] delay_tsc+0x3a/0xc0
<6>[   10.371589, 0] android_work: did not send uevent (0 0   (null))
<4>[   10.381171, 3]  [<c14954e3>] __const_udelay+0x23/0x30
<4>[   10.386207, 3]  [<c16d043a>] mdfld_dsi_send_dcs+0x12a/0x5d0
<4>[   10.391760, 3]  [<c186b6c6>] ? _raw_spin_unlock_irqrestore+0x26/0x50
<4>[   10.398101, 3]  [<c16af431>] ? ospm_power_using_hw_begin+0xa1/0x350
<4>[   10.399053, 3]  [<c186a49f>] ? __mutex_lock_slowpath+0x1ff/0x2f0
<4>[   10.399069, 3]  [<c16bd59e>] mdfld_dbi_update_panel+0x21e/0x2d0
<4>[   10.399085, 3]  [<c16b1ae1>] mdfld_te_handler_work+0x71/0x80
<4>[   10.399099, 3]  [<c12642be>] process_one_work+0xfe/0x3f0
<4>[   10.399114, 3]  [<c16b1a70>] ? mdfld_async_flip_te_handler+0xf0/0xf0

Basically, __run_hrtimer has a race with enqueue_hrtimer. When __run_hrtimer calls
the timer callback fn, another thread might call enqueue_hrtimer or hrtimer_start
to requeue it, and the timer->state is equal to HRTIMER_STATE_CALLBACK|HRTIMER_STATE_ENQUEUED,
which causes the BUG_ON(timer->state != HRTIMER_STATE_CALLBACK) checking fails.

The patch fixes it by checking only bit HRTIMER_STATE_CALLBACK.

Signed-off-by: Yanmin Zhang <yanmin.zhang@intel.com>
Reviewed-by: He, Bo <bo.he@intel.com>
use clamp_t in UNAME26 fix

The min/max call needed to have explicit types on some architectures
(e.g. mn10300). Use clamp_t instead to avoid the warning:

  kernel/sys.c: In function 'override_release':
  kernel/sys.c:1287:10: warning: comparison of distinct pointer types lacks a cast [enabled by default]

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ashmem: Fix ashmem_shrink deadlock.

Don't acquire ashmem_mutex in ashmem_shrink if we've somehow recursed into the
shrinker code from within ashmem. Just bail out, avoiding a deadlock. This is
fine, as ashmem cache pruning is advisory anyhow.

Signed-off-by: Robert Love <rlove@google.com>
arm/makefile: add build optimization
cpufreq: cpu-boost: Fix deadlock in wake_up of sync threads

If wake_up() is called on the current task on a CPU, the call will wait
until the current task is switched out before it wakes it up again and
returns.

The sync notifier for a CPU always runs on that CPU.

These two together can result in a deadlock if the sync notifier on CPU A
tries to wake up the sync thread of CPU A as it goes to sleep (is the
current task). A previous commit fixed this by adding a check to the sync
notifier to not wake up the sync thread of CPU A if it's the current task.

But this is still not sufficient to prevent deadlocks.

Sync thread of CPU A could be the current task on CPU B and sync thread of
CPU B could be the current task on CPU A.  At this point, if sync notifier
of CPU A and B try to wake up the sync threads of CPU A and B, it will
result in CPU A waiting for the current task in CPU B to get switched out
and CPU B waiting for the current task in CPU A to get switched out.  This
will result in a deadlock.

Prevent this scenario from happening by pinning the sync threads of each
CPU to run on that CPU. By doing this, we guarantee that sync notifiers
will only try to wake up sync threads running on that CPU. The fix added by
"cpufreq: cpu-boost: Resolve deadlock when waking up sync thread" ensures a
deadlock doesn't happen when a sync notifier tries to wake up a sync thread
running on that CPU.

Change-Id: I864e545529722a23886dd5a82f66089155d2d193
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: WhatHub <modernwhatever@gmail.com>
cpufreq: cpu-boost: Fix queue_delayed_work_on() race with hotplug

Calling queue_delayed_work_on() on a CPU that's in the process of getting
hotplugged out can result in that CPU infinitely looping in
msm_pm_wait_cpu_shutdown(). If queue_delayed_work_on() is called after the
CPU is hotplugged out, it could wake up the CPU without going through the
hotplug path and cause instability. To avoid this, make sure the CPU is and
stays online while queuing a work on it.

Change-Id: I1b4aae3db803e476b1a7676d08f495c1f38bb154
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: WhatHub <modernwhatever@gmail.com>
msm: mdss: Use interruptible threads

Based on @cyanogen's findings, use interruptible threads to reduce
cpu load.
smp: Add generic smpboot facility

Start a new file, which will hold SMP and CPU hotplug related generic
infrastructure.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124557.035417523@linutronix.de
smp: Provide generic idle thread allocation

All SMP architectures have magic to fork the idle task and to store it
for reusage when cpu hotplug is enabled. Provide a generic
infrastructure for it.

Create/reinit the idle thread for the cpu which is brought up in the
generic code and hand the thread pointer to the architecture code via
__cpu_up().

Note, that fork_idle() is called via a workqueue, because this
guarantees that the idle thread does not get a reference to a user
space VM. This can happen when the boot process did not bring up all
possible cpus and a later cpu_up() is initiated via the sysfs
interface. In that case fork_idle() would be called in the context of
the user space task and take a reference on the user space VM.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Acked-by: Venkatesh Pallipadi <venki@google.com>
Link: http://lkml.kernel.org/r/20120420124557.102478630@linutronix.de
smp, idle: Allocate idle thread for each possible cpu during boot

percpu areas are already allocated during boot for each possible cpu.
percpu idle threads can be considered as an extension of the percpu areas,
and allocate them for each possible cpu during boot.

This will eliminate the need for workqueue based idle thread allocation.
In future we can move the idle thread area into the percpu area too.

[ tglx: Moved the loop into smpboot.c and added an error check when
  the init code failed to allocate an idle thread for a cpu which
  should be onlined ]

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: venki@google.com
Link: http://lkml.kernel.org/r/1334966930.28674.245.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smpboot, idle: Optimize calls to smp_processor_id() in idle_threads_init()

While trying to initialize idle threads for all cpus, idle_threads_init()
calls smp_processor_id() in a loop, which is unnecessary. The intent
is to initialize idle threads for all non-boot cpus. So just use a variable
to note the boot cpu and use it in the loop.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: suresh.b.siddha@intel.com
Cc: venki@google.com
Cc: nikunj@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20120524151055.2549.64309.stgit@srivatsabhat.in.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smpboot, idle: Fix comment mismatch over idle_threads_init()

The comment over idle_threads_init() really talks about the functionality
of idle_init(). Move that comment to idle_init(), and add a suitable
comment over idle_threads_init().

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: suresh.b.siddha@intel.com
Cc: venki@google.com
Cc: nikunj@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20120524151100.2549.66501.stgit@srivatsabhat.in.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smpboot: Provide infrastructure for percpu hotplug threads

Provide a generic interface for setting up and tearing down percpu
threads.

On registration the threads for already online cpus are created and
started. On deregistration (modules) the threads are stoppped.

During hotplug operations the threads are created, started, parked and
unparked. The datastructure for registration provides a pointer to
percpu storage space and optional setup, cleanup, park, unpark
functions. These functions are called when the thread state changes.

Each implementation has to provide a function which is queried and
returns whether the thread should run and the thread function itself.

The core code handles all state transitions and avoids duplicated code
in the call sites.

[ paulmck: Preemption leak fix ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20120716103948.352501068@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hotplug: Fix UP bug in smpboot hotplug code

Because kernel subsystems need their per-CPU kthreads on UP systems as
well as on SMP systems, the smpboot hotplug kthread functions must be
provided in UP builds as well as in SMP builds.  This commit therefore
adds smpboot.c to UP builds and excludes irrelevant code via #ifdef.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smpboot: Allow selfparking per cpu threads

The stop machine threads are still killed when a cpu goes offline. The
reason is that the thread is used to bring the cpu down, so it can't
be parked along with the other per cpu threads.

Allow a per cpu thread to be excluded from automatic parking, so it
can park itself once it's done

Add a create callback function as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Richard Weinberger <rw@linutronix.de>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130131120741.553993267@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
kthread_worker: reorganize to prepare for flush_kthread_work() reimplementation

Make the following two non-functional changes.

* Separate out insert_kthread_work() from queue_kthread_work().

* Relocate struct kthread_flush_work and kthread_flush_work_fn()
  definitions above flush_kthread_work().

v2: Added lockdep_assert_held() in insert_kthread_work() as suggested
    by Andy Walls.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Andy Walls <awalls@md.metrocast.net>
kthread_worker: reimplement flush_kthread_work() to allow freeing the work item being executed

kthread_worker provides minimalistic workqueue-like interface for
users which need a dedicated worker thread (e.g. for realtime
priority).  It has basic queue, flush_work, flush_worker operations
which mostly match the workqueue counterparts; however, due to the way
flush_work() is implemented, it has a noticeable difference of not
allowing work items to be freed while being executed.

While the current users of kthread_worker are okay with the current
behavior, the restriction does impede some valid use cases.  Also,
removing this difference isn't difficult and actually makes the code
easier to understand.

This patch reimplements flush_kthread_work() such that it uses a
flush_work item instead of queue/done sequence numbers.

Signed-off-by: Tejun Heo <tj@kernel.org>