tcp: add a sysctl to config the tcp_default_init_rwnd

The default initial rwnd was hardcoded to 10.

Now we allow it to be controlled via
  /proc/sys/net/ipv4/tcp_default_init_rwnd
which limits the values from 3 to 100

This is somewhat needed because ipv6 routes are
autoconfigured by the kernel.

See "An Argument for Increasing TCP's Initial Congestion Window"
in https://developers.google.com/speed/articles/tcp_initcwnd_paper.pdf

Change-Id: I7eac8a0a5133371aea9ecb9aec0b608bd7f2cc57
Signed-off-by: JP Abgrall <jpa@google.com>
defconfig: disable KSM
Merge remote-tracking branch 'aosp-common/android-3.0' into kk-notest-cma
ARM: 7527/1: uaccess: explicitly check __user pointer when !CPU_USE_DOMAINS

commit 8404663f81d212918ff85f493649a7991209fa04 upstream.

The {get,put}_user macros don't perform range checking on the provided
__user address when !CPU_HAS_DOMAINS.

This patch reworks the out-of-line assembly accessors to check the user
address against a specified limit, returning -EFAULT if is is out of
range.

[will: changed get_user register allocation to match put_user]
[rmk: fixed building on older ARM architectures]

Change-Id: I3e3ddeaa51e47798bcf27181afd3785ccc015317
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "defconfig: disable KSM"

This reverts commit 99f0ed74977a475fd5926e9f0a20f6022a2a407b.
v4l: Fix use-after-free case in v4l2_device_release

Drivers that have no v4l2_device release callback might free the
v4l2_device instance in the video_device release callback. Make sure we
don't access the v4l2_device instance after it gets freed.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
videodev: fix a NULL pointer dereference in v4l2_device_release()

The change in 8280b66 does not cover the case when v4l2_dev is already
NULL, fix that.

With a Kinect sensor, seen as an USB camera using GSPCA in this context,
a NULL pointer dereference BUG can be triggered by just unplugging the
device after the camera driver has been loaded.

Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>