The current debug trap handling code does a number of things that are
illegal according to the AVR32 Architecture manual. Most importantly,
it may try to schedule from Debug Mode, thus clearing the D bit, which
can lead to "undefined behaviour".

It seems like this works in most cases, but several people have
observed somewhat unstable behaviour when debugging programs,
including soft lockups. So there's definitely something which is not
right with the existing code.

The new code will never schedule from Debug mode, it will always exit
Debug mode with a "retd" instruction, and if something not running in
Debug mode needs to do something debug-related (like doing a single
step), it will enter debug mode through a "breakpoint" instruction.
The monitor code will then return directly to user space, bypassing
its own saved registers if necessary (since we don't actually care
about the trapped context, only the one that came before.)

This adds three instructions to the common exception handling code,
including one branch. It does not touch super-hot paths like the TLB
miss handler.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Generate a new set of OCD register definitions in asm/ocd.h and rename
__mfdr() and __mtdr() to ocd_read() and ocd_write() respectively.

The bitfield definitions are a lot more complete now, and they are
entirely based on bit numbers, not masks. This is because OCD
registers are frequently accessed from assembly code, where bit
numbers are a lot more useful (can be fed directly to sbr, bfins,
etc.)

Bitfields that consist of more than one bit have two definitions:
_START, which indicates the number of the first bit, and _SIZE, which
indicates the number of bits. These directly correspond to the
parameters taken by the bfextu, bfexts and bfins instructions.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

The 'H' bit is bit 29, while the 'R' bit doesn't exist. Luckily, we
don't actually use any of the bits in question.

Also update show_regs() to show the Debug Mask and Debug state bits.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

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: NSerge E. Hallyn <serue@us.ibm.com>
Signed-off-by: NSukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: NPavel 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: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Introduce architecture dependent kretprobe blacklists to prohibit users
from inserting return probes on the function in which kprobes can be
inserted but kretprobes can not.

This patch also removes "__kprobes" mark from "__switch_to" on x86_64 and
registers "__switch_to" to the blacklist on x86-64, because that mark is to
prohibit user from inserting only kretprobe.
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As explained on:
http://www.avrfreaks.net/index.php?nameÿphpBB2&fileÿewtopic&tS307
If the current process is preempted before it can copy RAR_SUP and
RSR_SUP both register are lost and the process will segfault as soon
as it return from the syscall since the return adress will be
corrupted.

This patch disable IRQ as soon as we enter the syscall path and
reenable them when the copy is done.

In the interrupt handlers, check if we are interrupting the srrf
instruction, if so disable interrupts and return. The interrupt
handler will be re-called immediatly when the interrupts are
reenabled.

After some stressing workload:
 - find / > /dev/null in loop
 - top (in ssh)
 - ping -f avr32

The segfaults are not seen anymore.
Signed-off-by: NPhilippe Rétornaz <philippe.retornaz@epfl.ch>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

__init_end, which comes immediately before .text, is already page
aligned, and that should be more than enough for the .text section.

The reason why we need to align the .text section is because the
interrupt handler offset is ORed with EVBA, so we need to provide
enough alignment of EVBA that this OR operation works as an ADD.

Currently, the last interrupt handler is not nearly a full page away
from EVBA, so it won't be a problem.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Use PAGE_SIZE, THREAD_SIZE and L1_CACHE_BYTES instead of harcoded
constants in places where that's what we really mean.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Rename vmlinux.lds to a .S file to match other architectures.
Simplify Makefile to match the rename and deleted the unused
USE_STANDARD_AS_RULE
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NMatteo Vit - Dave S.r.l. <matteo.vit@dave.eu>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

This code is inside an #ifdef with a misspelled config symbol, so it
hasn't been used for a long time. Fix it before fixing the config
symbol to keep bisection working.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Identical implementations of PTRACE_POKEDATA go into generic_ptrace_pokedata()
function.

AFAICS, fix bug on xtensa where successful PTRACE_POKEDATA will nevertheless
return EPERM.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Identical implementations of PTRACE_PEEKDATA go into generic_ptrace_peekdata()
function.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the kernel OOPSed or BUGed then it probably should be considered as
tainted.  Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel.  This saves a lot of time explaining oddities in the
calltraces.
Signed-off-by: NPavel Emelianov <xemul@openvz.org>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
[ Added parisc patch from Matthew Wilson  -Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current generic bug implementation has a call to dump_stack() in case a
WARN_ON(whatever) gets hit.  Since report_bug(), which calls dump_stack(),
gets called from an exception handler we can do better: just pass the
pt_regs structure to report_bug() and pass it to show_regs() in case of a
warning.  This will give more debug informations like register contents,
etc...  In addition this avoids some pointless lines that dump_stack()
emits, since it includes a stack backtrace of the exception handler which
is of no interest in case of a warning.  E.g.  on s390 the following lines
are currently always present in a stack backtrace if dump_stack() gets
called from report_bug():

 [<000000000001517a>] show_trace+0x92/0xe8)
 [<0000000000015270>] show_stack+0xa0/0xd0
 [<00000000000152ce>] dump_stack+0x2e/0x3c
 [<0000000000195450>] report_bug+0x98/0xf8
 [<0000000000016cc8>] illegal_op+0x1fc/0x21c
 [<00000000000227d6>] sysc_return+0x0/0x10
Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
Acked-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With this consolidation we can now modify the .data
section definition in one spot for all archs.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Move definition of .text section to asm-generic.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Avoid the costly notifier list in the pagefault path and call
the kprobes code directly.  The same change went into the 2.6.22
cycle for powerpc, 2s390 and sparc64 already.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

The comment at the top of arch/avr32/kernel/irq.c doesn't really make
sense anymore since most of the actual interrupt handling code is
elsewhere.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Recently a few direct accesses to the thread_info in the task structure snuck
back, so this wraps them with the appropriate wrapper.
Signed-off-by: NRoman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Tested with a slightly hacked version of the test case included with
the original utimensat patch. All OK.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Rename .taglist to .taglist.init to silence section mismatch warnings.
The .taglist.init section was already placed in the .init output
section along with .init.text, so the warning didn't indicate any real
problems.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch moves the die notifier handling to common code.  Previous
various architectures had exactly the same code for it.  Note that the new
code is compiled unconditionally, this should be understood as an appel to
the other architecture maintainer to implement support for it aswell (aka
sprinkling a notify_die or two in the proper place)

arm had a notifiy_die that did something totally different, I renamed it to
arm_notify_die as part of the patch and made it static to the file it's
declared and used at.  avr32 used to pass slightly less information through
this interface and I brought it into line with the other architectures.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix vmalloc_sync_all bustage]
[bryan.wu@analog.com: fix vmalloc_sync_all in nommu]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reorder some instructions and change the register usage to reduce
the number of pipeline stalls. Also use the bfextu and bfins
instructions for bitfield manipulations instead of shifting and
masking.

This makes gzipping a 80MB file approximately 2% faster.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Since the core setup code takes care of both allocation and
reservation of framebuffer memory, there's no need for this board-
specific hook anymore. Replace it with two global variables,
fbmem_start and fbmem_size, which can be used directly.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

With the current strategy of using the bootmem allocator to allocate
or reserve framebuffer memory, there's a slight chance that the
requested area has been taken by the boot allocator bitmap before we
get around to reserving it.

By inserting the framebuffer region as a reserved region as early as
possible, we improve our chances for success and we make the region
visible as a reserved region in dmesg and /proc/iomem without any
extra work.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Use struct resource to specify both physical memory regions and
reserved regions and push everything into the same framework,
including kernel code/data and initrd memory. This allows us to get
rid of many special cases in the bootmem initialization and will also
make it easier to implement more robust handling of framebuffer
memory later.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Fix a problem with the NMI handler entry code related to the NMI handler
sharing some code with the exception handlers. This is not a good idea
because the RSR and RAR registers are not the same, and the NMI handler
runs with interrupts masked the whole time so there's no need to check
for pending work.

Open-code the low-level NMI handling logic instead so that the pt_regs
layout is actually correct when the higher-level handler is called.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

  * Use generic BUG() handling
  * Remove some useless debug statements
  * Use a common function _exception() to send signals or oops when
    an exception can't be handled. This makes sure init doesn't
    enter an infinite exception loop as well. Borrowed from powerpc.
  * Add some basic exception tracing support to the page fault code.
  * Rework dump_stack(), show_regs() and friends and move everything
    into process.c
  * Print information about configuration options and chip type when
    oopsing
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Clean up the cpu identification code, using definitions from
<asm/sysreg.h> instead of hardcoded constants. Also, add a features
bitmap to struct avr32_cpuinfo to allow other code to make decisions
based upon what the running cpu is actually capable of.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

This patch puts the CPU in sleep 0 when doing nothing, idle. This will
turn of the CPU clock and thus save power. The CPU is waken again when
an interrupt occurs.
Signed-off-by: NHans-Christian Egtvedt <hcegtvedt@atmel.com>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Due to limitation of the count-compare system timer (not able to
count when CPU is in sleep), the system timer had to be changed to
use a peripheral timer/counter.

The old COUNT-COMPARE code is still present in time.c as weak
functions. The new timer is added to the architecture directory.

This patch sets up TC0 as system timer The new timer has been tested
on AT32AP7000/ATSTK1000 at 100 Hz, 250 Hz, 300 Hz and 1000 Hz.

For more details about the timer/counter see the datasheet for
AT32AP700x available at

http://www.atmel.com/dyn/products/product_card.asp?part_id=3903Signed-off-by: NHans-Christian Egtvedt <hcegtvedt@atmel.com>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>