ARM: 8068/1: scoop: Remove unused variable

Remove the 'temp' variable in order to fix the following build warning:

arch/arm/common/scoop.c:185:6: warning: unused variable 'temp' [-Wunused-variable]

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8069/1: Make thread_save_fp macro aware of THUMB2 mode

The thread_save_fp macro has been defined so that it always reads the fp member
of the cpu_context_save struct. However, in the case of THUMB2 the fp is saved
not in the fp (r11) member but rather in r7.

This patch changes the way the macro is defined such that FP is read from the
correct place depending on whether we are a THUMB2 kernel or not. This enables
the backtrace in sitaution such as "echo t > /proc/sysrq-trigger" or the
function in which a process sleeping when "ps -Al" is invoked.

Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com>
Reviewed-by: Anurag Aggarwal <anurag19aggarwal@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: fix dependencies on PL310 errata symbols

A number of configurations spit out warnings similar to:

warning: (SOC_IMX6 && SOC_VF610 && ARCH_OMAP4) selects PL310_ERRATA_588369 which has unmet direct dependencies (CACHE_L2X0)
warning: (SOC_IMX6 && SOC_VF610 && ARCH_OMAP4) selects PL310_ERRATA_727915 which has unmet direct dependencies (CACHE_L2X0)

Clean up the dependencies here:
* PL310 symbols should only be selected when CACHE_L2X0 is enabled.
* Since the cache-l2x0 code detects PL310 presence at runtime, and we will
  eventually get rid of CACHE_PL310, surround these errata options with an
  if CACHE_L2X0 conditional rather than repeating the dependency against
  each.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: perf: fix compiler warning with gcc 4.6.4 (and tidy code)

GCC 4.6.4 spits out the following warning when building perf_event_v7.c:

arch/arm/kernel/perf_event_v7.c: In function 'krait_pmu_get_event_idx':
arch/arm/kernel/perf_event_v7.c:1927:6: warning: 'bit' may be used uninitialized in this function

While upgrading the version of gcc may solve this, the code can also be
organised to be more efficient by not carrying more local variables than
is necessary across the armv7pmu_get_event_idx function call.  If we set
'bit' to -1 (which is invalid for clear_bit) we can use that as an
indication whether we need to clear a bit after this function.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: arm925: ensure assembly sets up writethrough mapping

Commit ca8f0b0a545f ("ARM: ensure C page table setup code follows
assembly code") did what it said on the tin, but some of the older
CPU code omitted the default cache policy from their files.  This
results in the kernel running with the caches disabled.  Fix this
for ARM925.

Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
aio: fix aio request leak when events are reaped by userspace

The aio cleanups and optimizations by kmo that were merged into the 3.10
tree added a regression for userspace event reaping.  Specifically, the
reference counts are not decremented if the event is reaped in userspace,
leading to the application being unable to submit further aio requests.
This patch applies to 3.12+.  A separate backport is required for 3.10/3.11.
This issue was uncovered as part of CVE-2014-0206.

Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Petr Matousek <pmatouse@redhat.com>
aio: fix kernel memory disclosure in io_getevents() introduced in v3.10

A kernel memory disclosure was introduced in aio_read_events_ring() in v3.10
by commit a31ad380bed817aa25f8830ad23e1a0480fef797.  The changes made to
aio_read_events_ring() failed to correctly limit the index into
ctx->ring_pages[], allowing an attacked to cause the subsequent kmap() of
an arbitrary page with a copy_to_user() to copy the contents into userspace.
This vulnerability has been assigned CVE-2014-0206.  Thanks to Mateusz and
Petr for disclosing this issue.

This patch applies to v3.12+.  A separate backport is needed for 3.10/3.11.

Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: stable@vger.kernel.org
Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

Pull ARM fixes from Russell King:
 "A number of low impact fixes, the most noticable one is the thumb2
  frame pointer fix.  We also fix a regression caused during this merge
  window with ARM925 CPUs running with caches disabled, and fix a number
  of warnings"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: arm925: ensure assembly sets up writethrough mapping
  ARM: perf: fix compiler warning with gcc 4.6.4 (and tidy code)
  ARM: l2c: fix dependencies on PL310 errata symbols
  ARM: 8069/1: Make thread_save_fp macro aware of THUMB2 mode
  ARM: 8068/1: scoop: Remove unused variable
Merge git://git.kvack.org/~bcrl/aio-fixes

Pull aio fixes from Ben LaHaise:
 "These fix a kernel memory disclosure issue (arbitrary kmap() &
  copy_to_user()) revealed in CVE-2014-0206 by changes that were
  introduced in v3.10"

* git://git.kvack.org/~bcrl/aio-fixes:
  aio: fix kernel memory disclosure in io_getevents() introduced in v3.10
  aio: fix aio request leak when events are reaped by userspace