hrtimer: Prevent hrtimer_enqueue_reprogram race

hrtimer_enqueue_reprogram contains a race which could result in
timer.base switch during unlock/lock sequence.

hrtimer_enqueue_reprogram is releasing the lock protecting the timer
base for calling raise_softirq_irqsoff() due to a lock ordering issue
versus rq->lock.

If during that time another CPU calls __hrtimer_start_range_ns() on
the same hrtimer, the timer base might switch, before the current CPU
can lock base->lock again and therefor the unlock_timer_base() call
will unlock the wrong lock.

[ tglx: Added comment and massaged changelog ]

Change-Id: I327d862c28f24b77a62861764393c4bf660a7318
Signed-off-by: Leonid Shatz <leonid.shatz@ravellosystems.com>
Signed-off-by: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1359981217-389-1-git-send-email-izik.eidus@ravellosystems.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: b22affe0aef429d657bc6505aacb1c569340ddd2
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Taniya Das <tdas@codeaurora.org>
msm: timer: Use 32768Hz GPT and SCLK on 8064 family

On 8064 SOC family, a dedicated XO is derived to support
sleep clock at 32768Hz unlike 8960 SOC family where TCXO
divider was used with effective freq. of 32765Hz.

CRs-fixed: 462079
Change-Id: I79142703c4ffac209f4dedeefebc235eeb8b140d
Signed-off-by: Jay Chokshi <jchokshi@codeaurora.org>
hrtimer: Don't reinitialize a cpu_base's lock on CPU_UP

The current code makes the assumption that a cpu_base lock cannot
be held if a CPU is offline, which is tragically wrong.

If a hrtimer is not queued, then it will not be migrated by
migrate_hrtimers() when a CPU is offlined. Therefore, the
hrtimer's cpu_base may still point to a CPU which has
subsequently gone offline if the timer wasn't enqueued at the
time the CPU went down.

Normally this wouldn't be a problem, but a cpu_base's lock is
blindly reinitialized each time a CPU is brought up. If a CPU is
brought online during the period that another thread is
performing a hrtimer operation on a stale hrtimer, then the lock
will be reinitialized under its feet, and a SPIN_BUG() like the
following will be observed:

 [  448.212369] BUG: spinlock already unlocked on CPU#3,
 swapper/3/0
[  448.217368]  lock: 0xc47b1a40, .magic: dead4ead, .owner:
swapper/3/0, .owner_cpu: -1
[  448.217398] [<c0014398>] (unwind_backtrace+0x0/0x120) from
[<c0269ab0>] (do_raw_spin_unlock+0x44/0xdc)
[  448.217419] [<c0269ab0>] (do_raw_spin_unlock+0x44/0xdc) from
[<c071bbb0>] (_raw_spin_unlock_irqrestore+0xc/0x38)
[  448.217438] [<c071bbb0>]
(_raw_spin_unlock_irqrestore+0xc/0x38) from [<c00aa498>]
(hrtimer_try_to_cancel+0xf8/0x10c)
[  448.217455] [<c00aa498>] (hrtimer_try_to_cancel+0xf8/0x10c)
from [<c00aa4bc>] (hrtimer_cancel+0x10/0x20)
[  448.217475] [<c00aa4bc>] (hrtimer_cancel+0x10/0x20) from
[<c00e6934>] (rcu_idle_exit_common+0x5c/0xe0)
[  448.217494] [<c00e6934>] (rcu_idle_exit_common+0x5c/0xe0) from
[<c00e6ae8>] (rcu_idle_exit+0x9c/0xb4)
[  448.217514] [<c00e6ae8>] (rcu_idle_exit+0x9c/0xb4) from
[<c000f2dc>] (cpu_idle+0x98/0xf0)
[  448.217529] [<c000f2dc>] (cpu_idle+0x98/0xf0) from
[<000081ac>] (0x81ac)

CRs-Fixed: 460670
Change-Id: I588f6a864054abe6d4c249aad815c6d2f5a54077
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
msm: dma: Moving queue_work() function within spinlock

Currently we are adding a dma command to the staged list with in a
spinlock and then adding to workqueue using queue_work after unlocking
the spinlock. With this there is chance of executing DMA commands in out
of order in below concurrency case.

Tread1                                Thread2
__msm_dmov_enqueue_cmd_ext
   spin_lock_irqsave(..)
   list_add_tail(..)
   spin_unlock_irqrestore(..)
       --PREEMPT--
                                      __msm_dmov_enqueue_cmd_ext
                                         spin_lock_irqsave(..)
                                         list_add_tail(..)
                                         spin_unlock_irqrestore(..)
                                         queue_work()
                                         ..
   queue_work()
So adding queue_work with in spin_lock will make sure that the
work added in the work_queue is processed in the same order as they
are added in staged_commands.

CRs-Fixed: 423190
Change-Id: I2ffd1327fb5f0cd1f06db7de9c026d1c4997fe4d
Acked-by: Gopi Krishna Nedanuri <gnedanur@qti.qualcomm.com>
Signed-off-by: Utsab Bose <ubose@codeaurora.org>
msm: 8064: add control to WLAN reset pin at boot

To add control to chip_pwd_l pin to make sure AR6004 in known state
at boot

Change-Id: Ia33bb96ecf8e1ab02eb81d43fd606563201000e6
Signed-off-by: Ming-yi Lin <mylin@codeaurora.org>
msm_fb: hdmi: Check for stale HDCP variables

Check for stale HDCP variables like An from previous authentication
failure. In case of stale data, wait for some time to make sure HDCP
has has fresh data.

Change-Id: I37685a0246f3b60c383e3bf8d024c2b13fb3e5f6
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>
Merge "msm: 8064: add control to WLAN reset pin at boot"
Merge "hrtimer: Don't reinitialize a cpu_base's lock on CPU_UP"
Merge "hrtimer: Prevent hrtimer_enqueue_reprogram race"
Merge "msm: timer: Use 32768Hz GPT and SCLK on 8064 family"
Merge "msm: dma: Moving queue_work() function within spinlock"
Merge "msm_fb: hdmi: Check for stale HDCP variables"