net: flow: Prevent bringing up new CPUs during per-CPU initialization

In a rare race-condition, it's possible that a CPU will be brought
online between when the for_each_online_cpu() loop executes to
call flow_cache_cpu_prepare(), and when the hotplug notifier for
calling this same function is registered. If this happens,
flow_cache_cpu_prepare() will never be called for the new CPU,
resulting in crashes due to uninitialized per-cpu data.

Fix this by preventing CPUs from being added or removed during
this small but sensitive window.

Change-Id: Iafbbaa8a50e5c527392d130561874313720849d0
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
cpufreq: Manage only online cpus

cpufreq core doesn't manage offline cpus and if driver->init() has returned
mask including offline cpus, it may result in unwanted behavior by cpufreq core
or governors.

We need to get only online cpus in this mask. There are two places to fix this
mask, cpufreq core and cpufreq driver. It makes sense to do this at common place
and hence is done in core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
ARM: hw_breakpoint: Clear breakpoints before enabling monitor mode

The reset value of the BCR, BVR, WCR, and WVR registers are all
UNKNOWN on ARMv7. Unfortunately, reset_ctrl_regs() clears these
registers *after* enabling monitor mode, not before, and so some
implementations may experience UNPREDICTABLE behavior if the
reset values of these registers are non-zero. Clear the
breakpoints before enabling monitor mode so that we don't
experience boot hangs/loops due to breakpoints being enabled
out of reset.

Change-Id: I029fbe40725e803183544ddd6fe40285de4137e8
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
ARM: hw_breakpoint: enable HAVE_HW_BREAKPOINT feature flag

HAVE_HW_BREAKPOINT was disabled temporarily from commit
480a82f59712136b51ee5ca05c4f22c1738010c5. Issue not seen with the
latest kernel hence re-enable the feature and fix merge issue from
previous kernel upgrade.

Change-Id: Ia6e7e8282c848dd73108e4d951b3375bb7caa63c
Signed-off-by: Jin Hong <jinh@codeaurora.org>
Signed-off-by: Taniya Das <tdas@codeaurora.org>
cpufreq: ondemand: Fix update_sampling_rate race with hotplug

update_sampling_rate has a for loop which goes through each
online cpu and possibly queue up the ondemand work for them.
But while doing this it doesnt take any hotplug lock which
could potentially cause a race condition where ondemand work
is queued after the hotplug code (which sets the policy to NULL)
in the governor has cancelled any pending work. This could cause
a crash while trying to access the NULL policy in dbs_check_cpu.

Protecting the for_each_online_cpu loop with get_online_cpus()
and put_online_cpus().

Change-Id: Ia3f43ca7e4bed542834ab03ca1191d728f13311c
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: Save user policy min/max instead of policy min/max during hotplug

When a CPU is hotplugged off, various fields of the policy are saved so
that they can be restored when the CPU is hotplugged back in.

The existing code saves the policy min/max field during hotplug remove and
restores it into user policy min/max during hotplug add. This results in
the loss of the user policy min/max values across a hotplug remove/add.

Fix it by saving the user policy min/max instead of policy min/max during
hotplug remove. During a hotplug add, after user policy min/max is
restored, the policy min/max is already recomputed. So, there's no risk of
going beyound any limits imposed by the CPUFREQ_ADJUST/INCOMPATIBLE
notifiers.

Change-Id: Ib8e09fa324c1f80f095c5754b5dcf2685e8e4a66
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
cpufreq: ondemand: Fix store_powersave_bias() race with hotplug

store_powersave_bias() assumes that CPUs will not be taken offline or
brought online while executing its for_each_online_cpu() loops. Fix
this race by blocking hotplug while executing in these loop.

CRs-Fixed: 494407
Change-Id: I0d5520444ec21a8d9b12fb73c06ac8442449fa85
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
cpufreq: ondemand: Fix locking in store_powersave_bias

store_powersave_bias() assumes that dbs_info->cur_policy will
not change while it is executing. If it does, memory corruption
can potentially result. Fix this by acquiring the dbs_lock.

Most noticeably, this resolves timer-related list corruptions
encountered when queue_delayed_work_on() is called from within
store_powersave_bias() while a CPU is being hotplugged in and
out.

CRs-Fixed: 494407
Change-Id: I0fd5cbef6834545274cad9481e574ec50b37b871
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
cpufreq: ondemand: Fix locking issue in store_powersave_bias

store_powersave_bias takes timer_mutex before calling dbs_timer_exit
which tries to cancel the delayed work do_dbs_timer which in turn
tries to take the same lock. This can cause a lock recursion under
the race condition where can cancel_delayed_work_sync is called
when the work has already started executing.

This can be avoided by taking that lock after calling
dbs_timer_exit.

Change-Id: I7f862286e66f1ddc1e13e4eeee369dd188fc10d5
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
msm: cpufreq: Only apply driver limits for scaling_min/max_freq writes

When new values are written to scaling_min/max_freq sysfs files, the
current code applies all the limits imposed by various ADJUST and
INCOMPATIBLE notifiers handlers before storing them.

When the ADJUST and/or INCOMPATIBLE notifiers change their limits
frequently, this behavior makes it almost impossible for a
user/userspace process to store the scaling_min/max_freq limits
that go beyond the instantaneous limits imposed by the notifiers.
Since these sysfs nodes are typically meant to set limits that need
to be enforced for the foreseeable future, this is not a very user
friendly behavior.

So, change the behavior to only apply limits that are enforced by
the cpufreq driver. Typically, these are just the absolute limits
of the HW and don't change very often.

Change-Id: I1ccfaa2d1ee4ea595f882485d359dbdb407a0176
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>
cpufreq: ondemand: Fix hotplug deadlock with store_powersave_bias

store_powersave_bias() acquires the hotplug lock and the dbs_mutex
lock, but does so in the wrong order.  Deadlocks like the following
can result.

Thread A:
    get_online_cpus+0x3c/0x5c           <- acquires 'cpu_hotplug.lock'
    store_powersave_bias+0x80/0x3f4     <- acquires 'dbs_mutex'
    kobj_attr_store+0x14/0x20
    sysfs_write_file+0x108/0x13c
    vfs_write+0xb0/0x128
    sys_write+0x38/0x64

Thread B:
    cpufreq_governor_dbs+0x7c/0x55c     <- acquires 'dbs_mutex'
    __cpufreq_governor+0x90/0xe0
    __cpufreq_set_policy+0x1b0/0x258
    cpufreq_add_dev_interface+0x2cc/0x334
    cpufreq_add_dev+0x514/0x580
    cpufreq_cpu_callback+0x88/0x9c
    notifier_call_chain+0x38/0x68
    __cpu_notify+0x28/0x40
    _cpu_up+0xe4/0x118                  <- acquires 'cpu_hotplug.lock'
    cpu_up+0x64/0x80
    store_online+0x48/0x78
    dev_attr_store+0x18/0x24
    sysfs_write_file+0x108/0x13c
    vfs_write+0xb0/0x128
    sys_write+0x38/0x64

Fix this by flipping the order in which the locks are acquired and
released in store_powersave_bias so that it is the same as in the
hotplug path.

Change-Id: Idc59fb29d60b8f7fceb8ed0f2bb9eff4670abda7
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
msm: video: increase MM heap size for smoothstreaming
Increase MM carveout size to 76M to support 1080P secure
playback with worst-case allocation for smoothstreaming.
Restrict dpb count to 14 for smoothstreaming mode.
b/ 9302522
msm: display: Add DSI clock control for MDP GDHS power collapse

Enable DSI clock and regulator before enabling/disabling power collapse
for MDP GDHS.

(cherry picked from commit ad3200279e62eff01fd1bb9136cc9c0d11e10380)

(cherry picked from commit 58c5992c710df379e26bb210e00c74da501db9d2)

Change-Id: I76b91260c61abf214e688c0dea6989ed2cfa3801
Signed-off-by: Ravishangar Kalyanam <rkalya@codeaurora.org>
Signed-off-by: Siddhartha Agrawal <agrawals@codeaurora.org>
Signed-off-by: Ram Kumar Chakravarthy Chebathini <rcheba@codeaurora.org>

Conflicts:

	arch/arm/mach-msm/board-8064-regulator.c

Signed-off-by: Dhivya Subramanian <dthiru@codeaurora.org>
config:enable -03