linux-stable.git/arch/score, branch v3.12.52

arch: Clean up asm/barrier.h implementations using asm-generic/barrier.h

2015-10-28T15:37:39+00:00

commit 93ea02bb84354370e51de803a9405f171f3edf88 upstream.

We're going to be adding a few new barrier primitives, and in order to
avoid endless duplication make more agressive use of
asm-generic/barrier.h.

Change the asm-generic/barrier.h such that it allows partial barrier
definitions and fills out the rest with defaults.

There are a few architectures (m32r, m68k) that could probably
do away with their barrier.h file entirely but are kept for now due to
their unconventional nop() implementation.

Suggested-by: Geert Uytterhoeven 
Reviewed-by: "Paul E. McKenney" 
Reviewed-by: Mathieu Desnoyers 
Signed-off-by: Peter Zijlstra 
Cc: Michael Ellerman 
Cc: Michael Neuling 
Cc: Russell King 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Victor Kaplansky 
Cc: Tony Luck 
Cc: Oleg Nesterov 
Cc: Benjamin Herrenschmidt 
Cc: Frederic Weisbecker 
Link: http://lkml.kernel.org/r/20131213150640.846368594@infradead.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Jiri Slaby

vm: add VM_FAULT_SIGSEGV handling support

2015-03-12T16:31:25+00:00

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 
Tested-by: Jan Engelhardt 
Acked-by: Heiko Carstens  # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds 
Signed-off-by: Jiri Slaby

Score: Modify the Makefile of Score, remove -mlong-calls for compiling

2013-09-25T19:46:03+00:00

Signed-off-by: Lennox Wu

Score: Implement the function csum_ipv6_magic

2013-09-25T19:46:03+00:00

Signed-off-by: Lennox Wu

Score: The commit is for compiling successfully.

2013-09-25T19:46:03+00:00

	The modifications include:
	1. Kconfig of Score: we don't support ioremap
	2. Missed headfile including
	3. There are some errors in other people's commit not checked by us, we fix it now
	3.1 arch/score/kernel/entry.S: wrong instructions
	3.2 arch/score/kernel/process.c : just some typos

	Signed-off-by: Lennox Wu

Remove GENERIC_HARDIRQ config option

2013-09-13T13:09:52+00:00

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

arch: mm: pass userspace fault flag to generic fault handler

2013-09-12T22:38:01+00:00

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 
Reviewed-by: Michal Hocko 
Cc: David Rientjes 
Cc: KAMEZAWA Hiroyuki 
Cc: azurIt 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arch: mm: remove obsolete init OOM protection

2013-09-12T22:38:01+00:00

The memcg code can trap tasks in the context of the failing allocation
until an OOM situation is resolved.  They can hold all kinds of locks
(fs, mm) at this point, which makes it prone to deadlocking.

This series converts memcg OOM handling into a two step process that is
started in the charge context, but any waiting is done after the fault
stack is fully unwound.

Patches 1-4 prepare architecture handlers to support the new memcg
requirements, but in doing so they also remove old cruft and unify
out-of-memory behavior across architectures.

Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel
faults, because they can gracefully unwind the stack with -ENOMEM.  OOM
handling is restricted to user triggered faults that have no other
option.

Patch 6 reworks memcg's hierarchical OOM locking to make it a little
more obvious wth is going on in there: reduce locked regions, rename
locking functions, reorder and document.

Patch 7 implements the two-part OOM handling such that tasks are never
trapped with the full charge stack in an OOM situation.

This patch:

Back before smart OOM killing, when faulting tasks were killed directly on
allocation failures, the arch-specific fault handlers needed special
protection for the init process.

Now that all fault handlers call into the generic OOM killer (see commit
609838cfed97: "mm: invoke oom-killer from remaining unconverted page
fault handlers"), which already provides init protection, the
arch-specific leftovers can be removed.

Signed-off-by: Johannes Weiner 
Reviewed-by: Michal Hocko 
Acked-by: KOSAKI Motohiro 
Cc: David Rientjes 
Cc: KAMEZAWA Hiroyuki 
Cc: azurIt 
Acked-by: Vineet Gupta 	[arch/arc bits]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arch: : Kconfig: add "kernel/Kconfig.freezer" to "arch//Kconfig"

2013-08-14T00:57:49+00:00

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 
Cc: Richard Kuo 
Cc: Jonas Bonn 
Cc: Chen Liqin 
Cc: Lennox Wu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

score: delete __cpuinit usage from all score files

2013-07-14T23:36:56+00:00

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/score uses of the __cpuinit macros from
all C files.  Currently score does not have any __CPUINIT used in
assembly files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Chen Liqin 
Cc: Lennox Wu 
Signed-off-by: Paul Gortmaker

linux-stable.git/arch/score, branch v3.12.52

arch: Clean up asm/barrier.h implementations using asm-generic/barrier.h

vm: add VM_FAULT_SIGSEGV handling support

Score: Modify the Makefile of Score, remove -mlong-calls for compiling

Score: Implement the function csum_ipv6_magic

Score: The commit is for compiling successfully.

Remove GENERIC_HARDIRQ config option

arch: mm: pass userspace fault flag to generic fault handler

arch: mm: remove obsolete init OOM protection

arch: *: Kconfig: add "kernel/Kconfig.freezer" to "arch/*/Kconfig"

score: delete __cpuinit usage from all score files

arch: : Kconfig: add "kernel/Kconfig.freezer" to "arch//Kconfig"