eventpoll: fix uninitialized variable in epoll_ctl

When calling epoll_ctl with operation EPOLL_CTL_DEL, structure epds is
not initialized but ep_take_care_of_epollwakeup reads its event field.
When this unintialized field has EPOLLWAKEUP bit set, a capability check
is done for CAP_BLOCK_SUSPEND in ep_take_care_of_epollwakeup.  This
produces unexpected messages in the audit log, such as (on a system
running SELinux):

    type=AVC msg=audit(1408212798.866:410): avc:  denied
    { block_suspend } for  pid=7754 comm="dbus-daemon" capability=36
    scontext=unconfined_u:unconfined_r:unconfined_t
    tcontext=unconfined_u:unconfined_r:unconfined_t
    tclass=capability2 permissive=1

    type=SYSCALL msg=audit(1408212798.866:410): arch=c000003e syscall=233
    success=yes exit=0 a0=3 a1=2 a2=9 a3=7fffd4d66ec0 items=0 ppid=1
    pid=7754 auid=1000 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0
    fsgid=0 tty=(none) ses=3 comm="dbus-daemon"
    exe="/usr/bin/dbus-daemon"
    subj=unconfined_u:unconfined_r:unconfined_t key=(null)

("arch=c000003e syscall=233 a1=2" means "epoll_ctl(op=EPOLL_CTL_DEL)")

Remove use of epds in epoll_ctl when op == EPOLL_CTL_DEL.

Fixes: ("epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
futex: Unlock hb->lock in futex_wait_requeue_pi() error path

futex_wait_requeue_pi() calls futex_wait_setup(). If
futex_wait_setup() succeeds it returns with hb->lock held and
preemption disabled. Now the sanity check after this does:

        if (match_futex(&q.key, &key2)) {
	   	ret = -EINVAL;
		goto out_put_keys;
	}

which releases the keys but does not release hb->lock.

So we happily return to user space with hb->lock held and therefor
preemption disabled.

Unlock hb->lock before taking the exit route.

Reported-by: Dave "Trinity" Jones <davej@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1409112318500.4178@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Revert "Reduce min capture period size from 320 to 64"

This reverts commit b284191d1b9d2f750edeb406d186d22da12160a0.
ASoC: msm: EOS timeout now based on audio data

The timeout value, in relation to waiting for the
EOS command completion message from ADSP, is now
based on the time it will take the ADSP to stream
the remaining audio buffers.

Signed-off-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ASoC: wcd9xxx: Check headset insertion for consistency

 * It's possible to get a noisy reading during polling when
   transitioning to PLUG_TYPE_HEADSET. Poll again to double
   check that it's really a headset.
 * This helps when music is at full volume and a headphone
   is inserted. Double-checking the reading vastly improves
   the case where a noisy reading causes a mic to be detected.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
SELinux: use ARRAY_SIZE

ARRAY_SIZE is more concise to use when the size of an array is divided
by the size of its type or the size of its first element.

The Coccinelle semantic patch that makes this change is as follows:

// <smpl>
@@
type T;
T[] E;
@@

- (sizeof(E)/sizeof(E[...]))
+ ARRAY_SIZE(E)
// </smpl>

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
SELinux: possible NULL deref in context_struct_to_string

It's possible that the caller passed a NULL for scontext.  However if this
is a defered mapping we might still attempt to call *scontext=kstrdup().
This is bad.  Instead just return the len.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
net: Performance fix for process_backlog

In process_backlog the input_pkt_queue is only checked once for new
packets and quota is artificially reduced to reflect precisely the
number of packets on the input_pkt_queue so that the loop exits
appropriately.

This patches changes the behavior to be more straightforward and
less convoluted. Packets are processed until either the quota
is met or there are no more packets to process.

This patch seems to provide a small, but noticeable performance
improvement. The performance improvement is a result of staying
in the process_backlog loop longer which can reduce number of IPI's.

Performance data using super_netperf TCP_RR with 200 flows:

Before fix:

88.06% CPU utilization
125/190/309 90/95/99% latencies
1.46808e+06 tps
1145382 intrs.sec.

With fix:

87.73% CPU utilization
122/183/296 90/95/99% latencies
1.4921e+06 tps
1021674.30 intrs./sec.

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: intelli_hotplug: Fix build define
ARM: 7759/1: decouple CPU offlining from reboot/shutdown

Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.

In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.

In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.

Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.

Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by:  Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Restore DTS qcom,cpu-dma-latency-us back to 200 for all models.

Best to use default value here.
Revert "qup_i2c: Initialize I2C resource before registering."

This reverts commit 0234443282d9139dc9415ddb18b3575630b1482e.
Update audio_policy.conf thanks to @neobuddy89 and CM CAF.