This patch updates percpu related symbols in cpufreq such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/cpufreq/cpufreq.c: s/policy_cpu/cpufreq_policy_cpu/
* drivers/cpufreq/freq_table.c: s/show_table/cpufreq_show_table/
* arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: s/drv_data/acfreq_data/
  					      s/old_perf/acfreq_old_perf/

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>

This patch updates percpu related symbols in oprofile such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/oprofile/cpu_buffer.c: s/cpu_buffer/op_cpu_buffer/

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NRobert Richter <robert.richter@amd.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>

This patch updates percpu related symbols in kernel tracer such that
percpu symbols are unique and don't clash with local symbols.  This
serves two purposes of decreasing the possibility of global percpu
symbol collision and allowing dropping per_cpu__ prefix from percpu
symbols.

* kernel/trace/trace.c: s/max_data/max_tr_data/
* kernel/trace/trace_hw_branches: s/tracer/hwb_tracer/, s/buffer/hwb_buffer/

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>

This patch updates percpu related symbols under kernel/ and mm/ such
that percpu symbols are unique and don't clash with local symbols.
This serves two purposes of decreasing the possibility of global
percpu symbol collision and allowing dropping per_cpu__ prefix from
percpu symbols.

* kernel/lockdep.c: s/lock_stats/cpu_lock_stats/

* kernel/sched.c: s/init_rq_rt/init_rt_rq_var/	(any better idea?)
  		  s/sched_group_cpus/sched_groups/

* kernel/softirq.c: s/ksoftirqd/run_ksoftirqd/a

* kernel/softlockup.c: s/(*)_timestamp/softlockup_\1_ts/
  		       s/watchdog_task/softlockup_watchdog/
		       s/timestamp/ts/ for local variables

* kernel/time/timer_stats: s/lookup_lock/tstats_lookup_lock/

* mm/slab.c: s/reap_work/slab_reap_work/
  	     s/reap_node/slab_reap_node/

* mm/vmstat.c: local variable changed to avoid collision with vmstat_work

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: N(slab/vmstat) Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>

Make the following changes to remove some sparse warnings.

* Make DEFINE_PER_CPU_SECTION() declare __pcpu_unique_* before
  defining it.

* Annotate pcpu_extend_area_map() that it is entered with pcpu_lock
  held, releases it and then reacquires it.

* Make percpu related macros use unique nested variable names.

* While at it, add pcpu prefix to __size_call[_return]() macros as
  to-be-implemented sparse annotations will add percpu specific stuff
  to these macros.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>

alloc_percpu() couldn't handle array types like "int [100]" due to the
way return type was casted.  Fix it by using typeof() instead.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NFrederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>

vmalloc used non-existent percpu variable vmap_cpu_blocks instead of
the intended vmap_block_queue.  This went unnoticed because
put_cpu_var() didn't evaluate the parameter.  Fix it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>

ftrace_cpu_disabled usage in trace_functions_graph.c were left out
during this_cpu_xx conversion in commit 9288f99a causing compile
failure.  Convert them.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: Christoph Lameter <cl@linux-foundation.org>

this_cpu_xx can reduce the instruction count here and also
avoid address arithmetic.
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NTejun Heo <tj@kernel.org>

this_cpu_inc/dec reduces the number of instructions needed.
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Fix the following two compile warnings which show up on i386.

mm/percpu.c:1873: warning: comparison of distinct pointer types lacks a cast
mm/percpu.c:1879: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'size_t'
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NRandy Dunlap <randy.dunlap@oracle.com>

RCU does not do dynamic allocations but it increments per cpu variables
a lot. These instructions results in a move to a register and then back
to memory. This patch will make it use the inc/dec instructions on x86
that do not need a register.
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Using per cpu atomics for the vm statistics reduces their overhead.
And in the case of x86 we are guaranteed that they will never race even
in the lax form used for vm statistics.
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Just a slight optimization that removes one array lookup.
The processor number is needed for other things as well so the
get/put_cpu cannot be removed.
Acked-by: NTejun Heo <tj@kernel.org>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

The xfs_icsb_modify_counters() function no longer needs the cpu variable
if we use this_cpu_ptr() and we can get rid of get/put_cpu().
Acked-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NOlaf Weber <olaf@sgi.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

There are cases where we can use this_cpu_ptr and as the result
of using this_cpu_ptr() we no longer need to determine the
currently executing cpu.

In those places no get/put_cpu combination is needed anymore.
The local cpu variable can be eliminated.

Preemption still needs to be disabled and enabled since the
modifications of the per cpu variables is not atomic. There may
be multiple per cpu variables modified and those must all
be from the same processor.
Acked-by: NMaciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NTejun Heo <tj@kernel.org>
cc: Eric Biederman <ebiederm@aristanetworks.com>
cc: Stephen Hemminger <shemminger@vyatta.com>
cc: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Use this_cpu_ptr and __this_cpu_ptr in locations where straight
transformations are possible because per_cpu_ptr is used with
either smp_processor_id() or raw_smp_processor_id().

cc: David Howells <dhowells@redhat.com>
Acked-by: NTejun Heo <tj@kernel.org>
cc: Ingo Molnar <mingo@elte.hu>
cc: Rusty Russell <rusty@rustcorp.com.au>
cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Simplify NFS statistics and allow the use of optimized
arch instructions.
Acked-by: NTejun Heo <tj@kernel.org>
CC: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

SNMP statistic macros can be signficantly simplified.
This will also reduce code size if the arch supports these operations
in hardware.
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Basically the existing percpu ops can be used for this_cpu variants that allow
operations also on dynamically allocated percpu data. However, we do not pass a
reference to a percpu variable in. Instead a dynamically or statically
allocated percpu variable is provided.

Preempt, the non preempt and the irqsafe operations generate the same code.
It will always be possible to have the requires per cpu atomicness in a single
RMW instruction with segment override on x86.

64 bit this_cpu operations are not supported on 32 bit.
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

This patch introduces two things: First this_cpu_ptr and then per cpu
atomic operations.

this_cpu_ptr
------------

A common operation when dealing with cpu data is to get the instance of the
cpu data associated with the currently executing processor. This can be
optimized by

this_cpu_ptr(xx) = per_cpu_ptr(xx, smp_processor_id).

The problem with per_cpu_ptr(x, smp_processor_id) is that it requires
an array lookup to find the offset for the cpu. Processors typically
have the offset for the current cpu area in some kind of (arch dependent)
efficiently accessible register or memory location.

We can use that instead of doing the array lookup to speed up the
determination of the address of the percpu variable. This is particularly
significant because these lookups occur in performance critical paths
of the core kernel. this_cpu_ptr() can avoid memory accesses and

this_cpu_ptr comes in two flavors. The preemption context matters since we
are referring the the currently executing processor. In many cases we must
insure that the processor does not change while a code segment is executed.

__this_cpu_ptr 	-> Do not check for preemption context
this_cpu_ptr	-> Check preemption context

The parameter to these operations is a per cpu pointer. This can be the
address of a statically defined per cpu variable (&per_cpu_var(xxx)) or
the address of a per cpu variable allocated with the per cpu allocator.

per cpu atomic operations: this_cpu_*(var, val)
-----------------------------------------------
this_cpu_* operations (like this_cpu_add(struct->y, value) operate on
abitrary scalars that are members of structures allocated with the new
per cpu allocator. They can also operate on static per_cpu variables
if they are passed to per_cpu_var() (See patch to use this_cpu_*
operations for vm statistics).

These operations are guaranteed to be atomic vs preemption when modifying
the scalar. The calculation of the per cpu offset is also guaranteed to
be atomic at the same time. This means that a this_cpu_* operation can be
safely used to modify a per cpu variable in a context where interrupts are
enabled and preemption is allowed. Many architectures can perform such
a per cpu atomic operation with a single instruction.

Note that the atomicity here is different from regular atomic operations.
Atomicity is only guaranteed for data accessed from the currently executing
processor. Modifications from other processors are still possible. There
must be other guarantees that the per cpu data is not modified from another
processor when using these instruction. The per cpu atomicity is created
by the fact that the processor either executes and instruction or not.
Embedded in the instruction is the relocation of the per cpu address to
the are reserved for the current processor and the RMW action. Therefore
interrupts or preemption cannot occur in the mids of this processing.

Generic fallback functions are used if an arch does not define optimized
this_cpu operations. The functions come also come in the two flavors used
for this_cpu_ptr().

The firstparameter is a scalar that is a member of a structure allocated
through allocpercpu or a per cpu variable (use per_cpu_var(xxx)). The
operations are similar to what percpu_add() and friends do.

this_cpu_read(scalar)
this_cpu_write(scalar, value)
this_cpu_add(scale, value)
this_cpu_sub(scalar, value)
this_cpu_inc(scalar)
this_cpu_dec(scalar)
this_cpu_and(scalar, value)
this_cpu_or(scalar, value)
this_cpu_xor(scalar, value)

Arch code can override the generic functions and provide optimized atomic
per cpu operations. These atomic operations must provide both the relocation
(x86 does it through a segment override) and the operation on the data in a
single instruction. Otherwise preempt needs to be disabled and there is no
gain from providing arch implementations.

A third variant is provided prefixed by irqsafe_. These variants are safe
against hardware interrupts on the *same* processor (all per cpu atomic
primitives are *always* *only* providing safety for code running on the
*same* processor!). The increment needs to be implemented by the hardware
in such a way that it is a single RMW instruction that is either processed
before or after an interrupt.

cc: David Howells <dhowells@redhat.com>
cc: Ingo Molnar <mingo@elte.hu>
cc: Rusty Russell <rusty@rustcorp.com.au>
cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

With ia64 converted, there's no arch left which still uses legacy
percpu allocator.  Kill it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Delightedly-acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Lameter <cl@linux-foundation.org>

Unlike other archs, ia64 reserves space for percpu areas during early
memory initialization.  These areas occupy a contiguous region indexed
by cpu number on contiguous memory model or are grouped by node on
discontiguous memory model.

As allocation and initialization are done by the arch code, all that
setup_per_cpu_areas() needs to do is communicating the determined
layout to the percpu allocator.  This patch implements
setup_per_cpu_areas() for both contig and discontig memory models and
drops HAVE_LEGACY_PER_CPU_AREA.

Please note that for contig model, the allocation itself is modified
only to allocate for possible cpus instead of NR_CPUS.  As dynamic
percpu allocator can handle non-direct mapping, there's no reason to
allocate memory for cpus which aren't possible.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64 <linux-ia64@vger.kernel.org>

cpu0 used special percpu area reserved by the linker, __cpu0_per_cpu,
which is set up early in boot by head.S.  However, this doesn't
guarantee that the area will be on the same node as cpu0 and the
percpu area for cpu0 ends up very far away from percpu areas for other
cpus which cause problems for congruent percpu allocator.

This patch makes percpu area initialization allocate percpu area for
cpu0 like any other cpus and copy it from __cpu0_per_cpu which now
resides in the __init area.  This means that for cpu0, percpu area is
first setup at __cpu0_per_cpu early by head.S and then moved to an
area in the linear mapping during memory initialization and it's not
allowed to take a pointer to percpu variables between head.S and
memory initialization.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64 <linux-ia64@vger.kernel.org>

All information necessary to initialize cpu possible and present maps
are available once early_acpi_boot_init() is complete.  Reorganize
setup_arch() and acpi init functions such that,

* CPU information is printed after LAPIC entries are parsed in
  early_acpi_boot_init().

* smp_build_cpu_map() is called by setup_arch() instead of acpi
  functions.

* smp_build_cpu_map() is called once all CPU related information is
  available before memory is initialized.

This is primarily to allow find_memory() to use cpu maps but is also a
general cleanup.  Please note that with this change, the somewhat
ad-hoc early_cpu_possible_map defined and used for NUMA configurations
is probably unnecessary.  Something to clean up another day.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64 <linux-ia64@vger.kernel.org>

If CONFIG_VIRTUAL_MEM_MAP is enabled, ia64 defines macro VMALLOC_END
as unsigned long variable vmalloc_end which is adjusted to prepare
room for vmemmap.  This becomes probnlematic if a local variables
vmalloc_end is defined in some function (not very unlikely) and
VMALLOC_END is used in the function - the function thinks its
referencing the global VMALLOC_END value but would be referencing its
own local vmalloc_end variable.

There's no reason VMALLOC_END should be a macro.  Just define it as an
unsigned long variable if CONFIG_VIRTUAL_MEM_MAP is set to avoid nasty
surprises.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64 <linux-ia64@vger.kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix data space leak fix
  Btrfs: remove duplicates of filemap_ helpers
  Btrfs: take i_mutex before generic_write_checks
  Btrfs: fix arguments to btrfs_wait_on_page_writeback_range
  Btrfs: fix deadlock with free space handling and user transactions
  Btrfs: fix error cases for ioctl transactions
  Btrfs: Use CONFIG_BTRFS_POSIX_ACL to enable ACL code
  Btrfs: introduce missing kfree
  Btrfs: Fix setting umask when POSIX ACLs are not enabled
  Btrfs: proper -ENOSPC handling

spi_imx_chipselect() made things that should be (and mostly are) done by
spi_imx_setupxfer.  Only setting the tx and rx functions was missing.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Otherwise the config function uses random data from the stack.  This
didn't stick out because config is called once more in the chipselect
function with correct parameters.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

spi_imx_setup() is only called by spi_setup().  The latter does the
initialization already.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We can only setup the gpio pins in spi_setup time when we know the
SPI_CS_HIGH setting.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This makes the filename match the Kconfig symbol and the driver name.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's just a wrapper for <linux/fscache.h>, so remove it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When using %*s, sscanf should honor conversion specifiers immediately
following the %*s.  For example, the following code should find the
position of the end of the string "hello".

  int end;
  char buf[] = "hello    world";
  sscanf(buf, "%*s%n", &end);
  printf("%d\n", end);

Ideally, sscanf would advance the fmt and str pointers the same as it
would without the *, but the code for that is rather complicated and is
not included in the patch.
Signed-off-by: NAndy Spencer <andy753421@gmail.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow users to force skipping the TXEN test at init time. Applies
to all serial ports. Intended for debugging only.

There is a blacklist for devices where we need to skip the test but the
list is not complete.  This lets users force skipping the test so we can
determine if they need to be added to the list.

Some HP machines with weird serial consoles have this problem and there
may be more.
Signed-off-by: NChuck Ebbert <cebbert@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Check whether index is within bounds before grabbing the element.

Also, since NR_PORTS is defined ARRAY_SIZE(cy_port), cy_port[NR_PORTS] is
out of bounds as well.

[akpm@linux-foundation.org: cleanup, remove (long) casts]
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>