commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

commit 10f67dbf6add97751050f294d4c8e0cc1e5c2c23 upstream.

The mainline signal handling code for OpenRISC has been buggy since day
one with respect to syscall restart.  This patch significantly reworks
the signal handling code:

i)   Move the "work pending" loop to C code (borrowed from ARM arch)

ii)  Allow a tracer to muck about with the IP and skip syscall restart
     in that case (again, borrowed from ARM)

iii) Make signal handling WRT syscall restart actually work

v)   Make the signal handling code look more like that of other
     architectures so that it's easier for others to follow

Reported-by: Anders Nystrom <anders@southpole.se>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

Clean-up some copy/paste declarations that are not necessary. All the
functions either don't exist or are already declared in other headers.
This is needed in preparation of of_irq.h clean-up.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net

After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.

Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull device tree core updates from Grant Likely:
 "Generally minor changes.  A bunch of bug fixes, particularly for
  initialization and some refactoring.  Most notable change if feeding
  the entire flattened tree into the random pool at boot.  May not be
  significant, but shouldn't hurt either"

Tim Bird questions whether the boot time cost of the random feeding may
be noticeable.  And "add_device_randomness()" is definitely not some
speed deamon of a function.

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux:
  of/platform: add error reporting to of_amba_device_create()
  irq/of: Fix comment typo for irq_of_parse_and_map
  of: Feed entire flattened device tree into the random pool
  of/fdt: Clean up casting in unflattening path
  of/fdt: Remove duplicate memory clearing on FDT unflattening
  gpio: implement gpio-ranges binding document fix
  of: call __of_parse_phandle_with_args from of_parse_phandle
  of: introduce of_parse_phandle_with_fixed_args
  of: move of_parse_phandle()
  of: move documentation of of_parse_phandle_with_args
  of: Fix missing memory initialization on FDT unflattening
  of: consolidate definition of early_init_dt_alloc_memory_arch()
  of: Make of_get_phy_mode() return int i.s.o. const int
  include: dt-binding: input: create a DT header defining key codes.
  of/platform: Staticize of_platform_device_create_pdata()
  of: Specify initrd location using 64-bit
  dt: Typo fix
  OF: make of_property_for_each_{u32|string}() use parameters if OF is not enabled

Most architectures use the same implementation. Collapse the common ones
into a single weak function that can be overridden.

Signed-off-by: Grant Likely <grant.likely@linaro.org>

Linux 3.11-rc7

This patch removes the declaration of the function 'of_get_cpu_node'
which is not defined for openrisc. This is in preparation to move
it's definition from PPC to DT common code.

Again it could be there as it was originally copied from powerpc.

Acked-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>

All architectures include "kernel/Kconfig.freezer" except three left, so
let them include it too, or 'allmodconfig' will report error.

The related errors: (with allmodconfig for openrisc):

    CC      kernel/cgroup_freezer.o
  kernel/cgroup_freezer.c: In function 'freezer_css_online':
  kernel/cgroup_freezer.c:133:15: error: 'system_freezing_cnt' undeclared (first use in this function)
  kernel/cgroup_freezer.c:133:15: note: each undeclared identifier is reported only once for each function it appears in
  kernel/cgroup_freezer.c: In function 'freezer_css_offline':
  kernel/cgroup_freezer.c:157:15: error: 'system_freezing_cnt' undeclared (first use in this function)
  kernel/cgroup_freezer.c: In function 'freezer_attach':
  kernel/cgroup_freezer.c:200:4: error: implicit declaration of function 'freeze_task'
  kernel/cgroup_freezer.c: In function 'freezer_apply_state':
  kernel/cgroup_freezer.c:371:16: error: 'system_freezing_cnt' undeclared (first use in this function)

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>