ar:Makefile: improved build flags
Revert "msm: Make CONFIG_STRICT_MEMORY_RWX even stricter"

This reverts commit 8fe81dea367b8b9998dbfd0d27acf59dc566f494.
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.

Conflicts:
	drivers/cpufreq/cpufreq.c

Change-Id: I3aafa0d4e18363e1d68535f513099ecd27024007
cpufreq: ondemand: Use hotplug thread infrastructure

The dbs_sync threads caused considerable load, even when ondemand
wasn't even active. Use the hotplug thread infrastructure to park
the threads.

Change-Id: I8e2c780e3f00b73edc0337e01c226386146e0fd4
cpufreq: ondemand: Remove unused waitqueue

Change-Id: Iee8bb3b319be81fd232e3acf392c9548fec71320
msm: HTC: minor set_backlight function cleanup

* Remove pass-through set_backlight functions
* Remove stored backlight values: these were either unused or redundant
  to the checks performed in msm_fb.c

Change-Id: I75e3accb635831ed1f6b00e57ecd089778142c8d
cm3629: Restore stock sleeps

The sleeps inside lightsensor_enable are necessary to prevent the
backlight work queue filling before sensor values are ready. The sleep
inside psensor_enable seems to not be necessary, so it remains excluded,
cutting down on screen-on lag.

Change-Id: I107d7c09d199b332bf192a1c6e5f83be44e8dc7f
leds: tps61310_flashlight: Add additional video torch nodes

Change-Id: Id4f00949e9ac0832cffa9cebd8e6d2d328315647
ksm: check and skip page, if it is already scanned

On system like Android where most of the process are forked
from parent w/o execve, KSM can scan same page multiple times
in one scan cycle. There is no advantage in scanning same page
multiple times for merging. During testing with Android, it was
observed around 60% pages are skipped for each scan cycle.

Change-Id: I0cf01802f0b4d61fcab92558beb9e1c660dc9a77
Link: http://lkml.kernel.org/r/CAMrOTPgBtANS_ryRjan0-dTL97U7eRvtf3dCsss=Kn+Uk89fuA@mail.gmail.com
Signed-off-by: Pradeep Sawlani <sawlani@amazon.com>

Signed-off-by: Paul Reioux <reioux@gmail.com>
rtc: alarm: Proper handling of spinlock

In alarm_shutdown hook, taking interruptible mutex
lock in interrupt disabled context. This patch fixes
alarm_shutdown function to call rtc_read_time and
rtc_set_alarm APIs in interrupt enabled context.

Change-Id: I9392d8908c19365993dccc22504f4b6f83ae8f72
CRs-Fixed: 619657
Signed-off-by: Mohit Aggarwal <maggarwa@codeaurora.org>
staging: android: ashmem: Avoid deadlock with mmap/shrink

Both ashmem_mmap and ashmem_shrink take the ashmem_lock. It may
be possible for ashmem_mmap to invoke ashmem_shrink:

-000|mutex_lock(lock = 0x0)
-001|ashmem_shrink(?, sc = 0x0) <--- try to take ashmem_mutex again
-002|shrink_slab(shrink = 0xDA5F1CC0, nr_pages_scanned = 0, lru_pages
-002|=
-002|124)
-003|try_to_free_pages(zonelist = 0x0, ?, ?, ?)
-004|__alloc_pages_nodemask(gfp_mask = 21200, order = 1, zonelist =
-004|0xC11D0940,
-005|new_slab(s = 0xE4841E80, ?, node = -1)
-006|__slab_alloc.isra.43.constprop.50(s = 0xE4841E80, gfpflags =
-006|2148925462, ad
-007|kmem_cache_alloc(s = 0xE4841E80, gfpflags = 208)
-008|shmem_alloc_inode(?)
-009|alloc_inode(sb = 0xE480E800)
-010|new_inode_pseudo(?)
-011|new_inode(?)
-012|shmem_get_inode(sb = 0xE480E800, dir = 0x0, ?, dev = 0, flags =
-012|187)
-013|shmem_file_setup(?, ?, flags = 187)
-014|ashmem_mmap(?, vma = 0xC5D64210) <---- Acquire ashmem_mutex
-015|mmap_region(file = 0xDF8E2C00, addr = 1772974080, len = 233472,
-015|flags = 57,
-016|sys_mmap_pgoff(addr = 0, len = 230400, prot = 3, flags = 1, fd =
-016|157, pgoff
-017|ret_fast_syscall(asm)
-->|exception
-018|NUR:0x40097508(asm)
---|end of frame

Avoid this deadlock by using mutex_trylock in ashmem_shrink; if the mutex
is already held, do not attempt to shrink.

Change-Id: I222bbf55856d5849da813b730de0636c80966c8e
CRs-Fixed: 608832
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
random: allow architectures to optionally define random_get_entropy()

Allow architectures which have a disabled get_cycles() function to
provide a random_get_entropy() function which provides a fine-grained,
rapidly changing counter that can be used by the /dev/random driver.

For example, an architecture might have a rapidly changing register
used to control random TLB cache eviction, or DRAM refresh that
doesn't meet the requirements of get_cycles(), but which is good
enough for the needs of the random driver.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
random: mix in architectural randomness earlier in extract_buf()

Previously if CPU chip had a built-in random number generator (i.e.,
RDRAND on newer x86 chips), we mixed it in at the very end of
extract_buf() using an XOR operation.

We now mix it in right after the calculate a hash across the entire
pool.  This has the advantage that any contribution of entropy from
the CPU's HWRNG will get mixed back into the pool.  In addition, it
means that if the HWRNG has any defects (either accidentally or
maliciously introduced), this will be mitigated via the non-linear
transform of the SHA-1 hash function before we hand out generated
output.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Revert "ksm: check and skip page, if it is already scanned"

This reverts commit 2e6d7995fe1d2beae5acefea50c4cc7aac254ab0.
random: statically compute poolbitshift, poolbytes, poolbits

Use a macro to statically compute poolbitshift (will be used in a
subsequent patch), poolbytes, and poolbits.  On virtually all
architectures the cost of a memory load with an offset is the same as
the one of a memory load.

It is still possible for this to generate worse code since the C
compiler doesn't know the fixed relationship between these fields, but
that is somewhat unlikely.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Conflicts:
	drivers/char/random.c
random: allow fractional bits to be tracked

Allow fractional bits of entropy to be tracked by scaling the entropy
counter (fixed point).  This will be used in a subsequent patch that
accounts for entropy lost due to overwrites.

[ Modified by tytso to fix up a few missing places where the
  entropy_count wasn't properly converted from fractional bits to
  bits. ]

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Conflicts:

	drivers/char/random.c

also sync with mainline kernel

Signed-off-by: Paul Reioux <reioux@gmail.com>
random: account for entropy loss due to overwrites

When we write entropy into a non-empty pool, we currently don't
account at all for the fact that we will probabilistically overwrite
some of the entropy in that pool.  This means that unless the pool is
fully empty, we are currently *guaranteed* to overestimate the amount
of entropy in the pool!

Assuming Shannon entropy with zero correlations we end up with an
exponentally decaying value of new entropy added:

	entropy <- entropy + (pool_size - entropy) *
		(1 - exp(-add_entropy/pool_size))

However, calculations involving fractional exponentials are not
practical in the kernel, so apply a piecewise linearization:

	  For add_entropy <= pool_size/2 then

	  (1 - exp(-add_entropy/pool_size)) >= (add_entropy/pool_size)*0.7869...

	  ... so we can approximate the exponential with
	  3/4*add_entropy/pool_size and still be on the
	  safe side by adding at most pool_size/2 at a time.

In order for the loop not to take arbitrary amounts of time if a bad
ioctl is received, terminate if we are within one bit of full.  This
way the loop is guaranteed to terminate after no more than
log2(poolsize) iterations, no matter what the input value is.  The
vast majority of the time the loop will be executed exactly once.

The piecewise linearization is very conservative, approaching 3/4 of
the usable input value for small inputs, however, our entropy
estimation is pretty weak at best, especially for small values; we
have no handle on correlation; and the Shannon entropy measure (Rényi
entropy of order 1) is not the correct one to use in the first place,
but rather the correct entropy measure is the min-entropy, the Rényi
entropy of infinite order.

As such, this conservatism seems more than justified.

This does introduce fractional bit values.  I have left it to have 3
bits of fraction, so that with a pool of 2^12 bits the multiply in
credit_entropy_bits() can still fit into an int, as 2*(3+12) < 31.  It
is definitely possible to allow for more fractional accounting, but
that multiply then would have to be turned into a 32*32 -> 64 multiply.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: DJ Johnston <dj.johnston@intel.com>
random: fix the tracepoint for get_random_bytes(_arch)

Fix a problem where get_random_bytes_arch() was calling the tracepoint
get_random_bytes().  So add a new tracepoint for
get_random_bytes_arch(), and make get_random_bytes() and
get_random_bytes_arch() call their correct tracepoint.

Also, add a new tracepoint for add_device_randomness()

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
random: optimize spinlock use in add_device_randomness()

The add_device_randomness() function calls mix_pool_bytes() twice for
the input pool and the non-blocking pool, for a total of four times.
By using _mix_pool_byte() and taking the spinlock in
add_device_randomness(), we can halve the number of times we need
take each pool's spinlock.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
random: optimize the entropy_store structure

Use smaller types to slightly shrink the size of the entropy store
structure.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>