ARM: 6269/1: Add 'code' parameter for hook_fault_code()

Add one more parameter to hook_fault_code() to be able to set 'code'
field of struct fsr_info.

Signed-off-by: Kirill A. Shutemov <kirill@shut

ARM: 6269/1: Add 'code' parameter for hook_fault_code()

Add one more parameter to hook_fault_code() to be able to set 'code'
field of struct fsr_info.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 6252/1: Use SIGBUS for unaligned access instead of SIGILL

POSIX specify to use signal SIGBUS with code BUS_ADRALN for invalid
address alignment.

Signed-off-by: Kirill A. Shutemov <kirill@shute

ARM: 6252/1: Use SIGBUS for unaligned access instead of SIGILL

POSIX specify to use signal SIGBUS with code BUS_ADRALN for invalid
address alignment.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 6166/1: Proper prefetch abort handling on pre-ARMv6

Instruction faults on pre-ARMv6 CPUs are interpreted as
a 'translation fault', but do_translation_fault doesn't
handle well if user mode tryi

ARM: 6166/1: Proper prefetch abort handling on pre-ARMv6

Instruction faults on pre-ARMv6 CPUs are interpreted as
a 'translation fault', but do_translation_fault doesn't
handle well if user mode trying to run instruction above
TASK_SIZE, and result in the infinite retry of that
instruction.

CC: <stable@kernel.org>
Signed-off-by: Anfei Zhou <anfei.zhou@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 6134/1: Handle instruction cache maintenance fault properly

Between "clean D line..." and "invalidate I line" operations in
v7_coherent_user_range(), the memory page may get swapped out.
And th

ARM: 6134/1: Handle instruction cache maintenance fault properly

Between "clean D line..." and "invalidate I line" operations in
v7_coherent_user_range(), the memory page may get swapped out.
And the fault on "invalidate I line" could not be properly handled
causing the oops.

In ARMv6 "external abort on linefetch" replaced by "instruction cache
maintenance fault". Let's handle it as translation fault. It fixes the
issue.

I'm not sure if it's reasonable to check arch version in run-time.
Let's do it in compile time for now.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Siarhei Siamashka <siarhei.siamashka@nokia.com>
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 5900/2: arm: enable support for software perf events

The perf events subsystem allows counting of both hardware and
software events. This patch implements the bare minimum for software
performa

ARM: 5900/2: arm: enable support for software perf events

The perf events subsystem allows counting of both hardware and
software events. This patch implements the bare minimum for software
performance events.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 5742/1: ARM: add debug check for invalid kernel page faults

According to the following in arch/arm/mm/fault.c page faults from
kernel mode are invalid if mmap_sem is already held and there is
n

ARM: 5742/1: ARM: add debug check for invalid kernel page faults

According to the following in arch/arm/mm/fault.c page faults from
kernel mode are invalid if mmap_sem is already held and there is
no exception handler defined for the faulting instruction:

/*
* As per x86, we may deadlock here. However, since the kernel only
* validly references user space from well defined areas of the code,
* we can bug out early if this is from code which shouldn't.
*/
if (!down_read_trylock(&mm->mmap_sem)) {
if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc))
goto no_context;

Since mmap_sem can be held at arbitrary times by another thread this
also means that any page faults from kernel mode are invalid if no
exception handler is defined for them, regardless whether mmap_sem is
held at the time of fault.

To easier detect code that can trigger the above error, add a check
also for the case where mmap_sem is acquired. As this has an overhead
make it a VM debug check.

Signed-off-by: Imre Deak <imre.deak@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 5728/1: Proper prefetch abort handling on ARMv6 and ARMv7

Currently, on ARMv6 and ARMv7, if an application tries to execute
code (or garbage) on non-executable page it hangs. It caused by
incor

ARM: 5728/1: Proper prefetch abort handling on ARMv6 and ARMv7

Currently, on ARMv6 and ARMv7, if an application tries to execute
code (or garbage) on non-executable page it hangs. It caused by
incorrect prefetch abort handling. Now every prefetch abort
processes as a translation fault.

To fix this we have to analyze instruction fault status register
to figure out reason why we've got the abort and process it
accordingly.

To make IFSR different from DFSR we set bit 31 which is reserved in
both IFSR and DFSR.

This patch also tries to protect from future hangs on unexpected
exceptions. An application will be killed if unexpected exception
type was received.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: 5727/1: Pass IFSR register to do_PrefetchAbort()

Instruction fault status register, IFSR, was introduced on ARMv6 to
provide status information about the last insturction fault. It
needed for p

ARM: 5727/1: Pass IFSR register to do_PrefetchAbort()

Instruction fault status register, IFSR, was introduced on ARMv6 to
provide status information about the last insturction fault. It
needed for proper prefetch abort handling.

Now we have three prefetch abort model:

* legacy - for CPUs before ARMv6. They doesn't provide neither
IFSR nor IFAR. We simulate IFSR with section translation fault
status for them to generalize code;
* ARMv6 - provides IFSR, but not IFAR;
* ARMv7 - provides both IFSR and IFAR.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: Add support for checking access permissions on prefetch aborts

ARMv6 introduces non-executable mappings, which can cause prefetch aborts
when an attempt is made to execute from such a mapping.

ARM: Add support for checking access permissions on prefetch aborts

ARMv6 introduces non-executable mappings, which can cause prefetch aborts
when an attempt is made to execute from such a mapping. Currently, this
causes us to loop in the page fault handler since we don't correctly
check for proper permissions.

Fix this by checking that VMAs have VM_EXEC set for prefetch aborts.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: Separate out access error checking

Since we get notified separately about prefetch aborts, which may be
permission faults, we need to check for appropriate access permissions
when handling a fa

ARM: Separate out access error checking

Since we get notified separately about prefetch aborts, which may be
permission faults, we need to check for appropriate access permissions
when handling a fault. This patch prepares us for doing this by
separating out the access error checking.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: Ensure correct might_sleep() check in pagefault path

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: Update page fault handling for new OOM techniques

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: Provide definitions and helpers for decoding the FSR register

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: implement highpte

Add the ARM implementation of highpte, which allows PTE tables to be
placed in highmem. Unfortunately, we do not offer highpte support
when support for L2 cache is enabled.

ARM: implement highpte

Add the ARM implementation of highpte, which allows PTE tables to be
placed in highmem. Unfortunately, we do not offer highpte support
when support for L2 cache is enabled.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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Include linux/sched.h in arch/arm/mm/fault.c

When building with !MMU, task_struct is not defined. Just include the
relevant file.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

nommu: Fix the fault processing for the MMU-less case

The patch adds the necessary ifdefs around functions that only make
sense when the MMU is enabled.

Signed-off-by: Catalin Marinas <catalin.mari

nommu: Fix the fault processing for the MMU-less case

The patch adds the necessary ifdefs around functions that only make
sense when the MMU is enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

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Move FAULT_FLAG_xyz into handle_mm_fault() callers

This allows the callers to now pass down the full set of FAULT_FLAG_xyz
flags to handle_mm_fault(). All callers have been (mechanically)
converted

Move FAULT_FLAG_xyz into handle_mm_fault() callers

This allows the callers to now pass down the full set of FAULT_FLAG_xyz
flags to handle_mm_fault(). All callers have been (mechanically)
converted to the new calling convention, there's almost certainly room
for architectures to clean up their code and then add FAULT_FLAG_RETRY
when that support is added.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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[ARM] remove bogus #ifdef CONFIG_HIGHMEM in show_pte()

The restriction on !CONFIG_HIGHMEM is unneeded since page tables are
currently never allocated with highmem pages, and actually disable PTE
dum

[ARM] remove bogus #ifdef CONFIG_HIGHMEM in show_pte()

The restriction on !CONFIG_HIGHMEM is unneeded since page tables are
currently never allocated with highmem pages, and actually disable PTE
dump whenever highmem is configured. Let's have a dynamic test to better
describe the current limitation instead.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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[ARM] Ensure linux/hardirqs.h is included where required

... for the removal of it from asm-generic/local.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

[ARM] 5272/1: remove conditional compilation in show_pte()

The PTRS_PER_PMD != 1 condition can be evaluated with C code and
optimized at compile time.

Signed-off-by: Nicolas Pitre <nico@marvell.com

[ARM] 5272/1: remove conditional compilation in show_pte()

The PTRS_PER_PMD != 1 condition can be evaluated with C code and
optimized at compile time.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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[ARM] Convert asm/uaccess.h to linux/uaccess.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM kprobes: prevent some functions involved with kprobes from being probed

Signed-off-by: Nicolas Pitre <nico@marvell.com>

ARM kprobes: add the kprobes hook to the page fault handler

Signed-off-by: Nicolas Pitre <nico@marvell.com>

pid namespaces: define is_global_init() and is_container_init()

is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().

A cgroup init has it's

pid namespaces: define is_global_init() and is_container_init()

is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().

A cgroup init has it's tsk->pid == 1.

A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns. But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.

Changelog:

2.6.22-rc4-mm2-pidns1:
- Use 'init_pid_ns.child_reaper' to determine if a given task is the
global init (/sbin/init) process. This would improve performance
and remove dependence on the task_pid().

2.6.21-mm2-pidns2:

- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
ppc,avr32}/traps.c for the _exception() call to is_global_init().
This way, we kill only the cgroup if the cgroup's init has a
bug rather than force a kernel panic.

[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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During VM oom condition, kill all threads in process group

We have had complaints where a threaded application is left in a bad state
after one of it's threads is killed when we hit a VM: out_of_mem

During VM oom condition, kill all threads in process group

We have had complaints where a threaded application is left in a bad state
after one of it's threads is killed when we hit a VM: out_of_memory
condition.

Killing just one of the process threads can leave the application in a bad
state, whereas killing the entire process group would allow for the
application to restart, or be otherwise handled, and makes it very obvious
that something has gone wrong.

This change allows the entire process group to be taken down, rather
than just the one thread.

Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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