Commit graph

1139 commits

Author SHA1 Message Date
Eric W. Biederman
7b21fddd08 ns: Wire up the setns system call
32bit and 64bit on x86 are tested and working.  The rest I have looked
at closely and I can't find any problems.

setns is an easy system call to wire up.  It just takes two ints so I
don't expect any weird architecture porting problems.

While doing this I have noticed that we have some architectures that are
very slow to get new system calls.  cris seems to be the slowest where
the last system calls wired up were preadv and pwritev.  avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h.  frv is
behind with perf_event_open being the last syscall wired up.  On h8300
the last system call wired up was epoll_wait.  On m32r the last system
call wired up was fallocate.  mn10300 has recvmmsg as the last system
call wired up.  The rest seem to at least have syncfs wired up which was
new in the 2.6.39.

v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall  conflicts.
v7: ported to Linus's latest post 2.6.39 tree.

>  arch/blackfin/include/asm/unistd.h     |    3 ++-
>  arch/blackfin/mach-common/entry.S      |    1 +
Acked-by: Mike Frysinger <vapier@gentoo.org>

Oh - ia64 wiring looks good.
Acked-by: Tony Luck <tony.luck@intel.com>

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-28 10:48:39 -07:00
Linus Torvalds
5129df03d0 Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Unify input section names
  percpu: Avoid extra NOP in percpu_cmpxchg16b_double
  percpu: Cast away printk format warning
  percpu: Always align percpu output section to PAGE_SIZE

Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun
2011-05-24 11:53:42 -07:00
Russell King
ec19628d72 Merge branches 'consolidate', 'ep93xx', 'fixes', 'misc', 'mmci', 'remove' and 'spear' into for-linus 2011-05-23 19:27:40 +01:00
Russell King
4b60e5f90d Merge branches 'consolidate-clksrc', 'consolidate-flash', 'consolidate-generic', 'consolidate-smp', 'consolidate-stmp' and 'consolidate-zones' into consolidate 2011-05-23 18:05:10 +01:00
Russell King
0f7b332f97 ARM: consolidate SMP cross call implementation
Rather than having each platform class provide a mach/smp.h header for
smp_cross_call(), arrange for them to register the function with the
core ARM SMP code instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-23 16:53:17 +01:00
Mark Rutland
57ce9bb39b ARM: 6902/1: perf: Remove erroneous check on active_events
When initialising a PMU, there is a check to protect against races with
other CPUs filling all of the available event slots. Since armpmu_add
checks that an event can be scheduled, we do not need to do this at
initialisation time. Furthermore the current code is broken because it
assumes that atomic_inc_not_zero will unconditionally increment
active_counts and then tries to decrement it again on failure.

This patch removes the broken, redundant code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-20 22:39:17 +01:00
Linus Torvalds
39ab05c8e0 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits)
  debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
  sysfs: remove "last sysfs file:" line from the oops messages
  drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION"
  memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION
  SYSFS: Fix erroneous comments for sysfs_update_group().
  driver core: remove the driver-model structures from the documentation
  driver core: Add the device driver-model structures to kerneldoc
  Translated Documentation/email-clients.txt
  RAW driver: Remove call to kobject_put().
  reboot: disable usermodehelper to prevent fs access
  efivars: prevent oops on unload when efi is not enabled
  Allow setting of number of raw devices as a module parameter
  Introduce CONFIG_GOOGLE_FIRMWARE
  driver: Google Memory Console
  driver: Google EFI SMI
  x86: Better comments for get_bios_ebda()
  x86: get_bios_ebda_length()
  misc: fix ti-st build issues
  params.c: Use new strtobool function to process boolean inputs
  debugfs: move to new strtobool
  ...

Fix up trivial conflicts in fs/debugfs/file.c due to the same patch
being applied twice, and an unrelated cleanup nearby.
2011-05-19 18:24:11 -07:00
Linus Torvalds
80fe02b5da Merge branches 'sched-core-for-linus' and 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
  sched: Fix and optimise calculation of the weight-inverse
  sched: Avoid going ahead if ->cpus_allowed is not changed
  sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
  sched: Remove unused parameters from sched_fork() and wake_up_new_task()
  sched: Shorten the construction of the span cpu mask of sched domain
  sched: Wrap the 'cfs_rq->nr_spread_over' field with CONFIG_SCHED_DEBUG
  sched: Remove unused 'this_best_prio arg' from balance_tasks()
  sched: Remove noop in alloc_rt_sched_group()
  sched: Get rid of lock_depth
  sched: Remove obsolete comment from scheduler_tick()
  sched: Fix sched_domain iterations vs. RCU
  sched: Next buddy hint on sleep and preempt path
  sched: Make set_*_buddy() work on non-task entities
  sched: Remove need_migrate_task()
  sched: Move the second half of ttwu() to the remote cpu
  sched: Restructure ttwu() some more
  sched: Rename ttwu_post_activation() to ttwu_do_wakeup()
  sched: Remove rq argument from ttwu_stat()
  sched: Remove rq->lock from the first half of ttwu()
  sched: Drop rq->lock from sched_exec()
  ...

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix rt_rq runtime leakage bug
2011-05-19 17:41:22 -07:00
Rafael J. Wysocki
2d2a9163bd Merge branch 'syscore' into for-linus
* syscore:
  PM: Remove sysdev suspend, resume and shutdown operations
  PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM
  PM / UNICORE32: Use struct syscore_ops instead of sysdevs for PM
  PM / AVR32: Use struct syscore_ops instead of sysdevs for PM
  PM / Blackfin: Use struct syscore_ops instead of sysdevs for PM
  ARM / Samsung: Use struct syscore_ops for "core" power management
  ARM / PXA: Use struct syscore_ops for "core" power management
  ARM / SA1100: Use struct syscore_ops for "core" power management
  ARM / Integrator: Use struct syscore_ops for core PM
  ARM / OMAP: Use struct syscore_ops for "core" power management
  ARM: Use struct syscore_ops instead of sysdevs for PM in common code
2011-05-17 23:23:40 +02:00
Dave Martin
5be6f62b00 ARM: 6883/1: ptrace: Migrate to regsets framework
This patch migrates the implementation of the ptrace interface for
the core integer registers, legacy FPA registers and VFP registers
to use the regsets framework.

As an added bonus, all this stuff gets included in coredumps
at no extra cost.  Without this patch, coredumps contained no
VFP state.

Third-party extension register sets (iwmmx, crunch) are not migrated
by this patch, and continue to use the old implementation;
these should be migratable without much extra work.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Will Deacon <Will.Deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-14 21:36:55 +01:00
Greg Kroah-Hartman
82a3242e11 sysfs: remove "last sysfs file:" line from the oops messages
On some arches (x86, sh, arm, unicore, powerpc) the oops message would
print out the last sysfs file accessed.

This was very useful in finding a number of sysfs and driver core bugs
in the 2.5 and early 2.6 development days, but it has been a number of
years since this file has actually helped in debugging anything that
couldn't also be trivially determined from the stack traceback.

So it's time to delete the line.  This is good as we need all the space
we can get for oops messages at times on consoles.

Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-13 16:05:51 -07:00
Linus Torvalds
75c0b3b466 Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses
  ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
  ARM: 6890/1: memmap: only free allocated memmap entries when using SPARSEMEM
  ARM: zImage: the page table memory must be considered before relocation
  ARM: zImage: make sure not to relocate on top of the relocation code
  ARM: zImage: Fix bad SP address after relocating kernel
  ARM: zImage: make sure the stack is 64-bit aligned
  ARM: RiscPC: acornfb: fix section mismatches
  ARM: RiscPC: etherh: fix section mismatches
2011-05-12 07:53:06 -07:00
Arnd Bergmann
2af68df02f ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
GDB's interrupt.exp test cases currenly fail on ARM.  The problem is how do_signal
handled restarting interrupted system calls:

The entry.S assembler code determines that we come from a system call; and that
information is passed as "syscall" parameter to do_signal.  That routine then
calls get_signal_to_deliver [*] and if a signal is to be delivered, calls into
handle_signal.  If a system call is to be restarted either after the signal
handler returns, or if no handler is to be called in the first place, the PC
is updated after the get_signal_to_deliver call, either in handle_signal (if
we have a handler) or at the end of do_signal (otherwise).

Now the problem is that during [*], the call to get_signal_to_deliver, a ptrace
intercept may happen.  During this intercept, the debugger may change registers,
including the PC.  This is done by GDB if it wants to execute an "inferior call",
i.e. the execution of some code in the debugged program triggered by GDB.

To this purpose, GDB will save all registers, allocate a stack frame, set up
PC and arguments as appropriate for the call, and point the link register to
a dummy breakpoint instruction.  Once the process is restarted, it will execute
the call and then trap back to the debugger, at which point GDB will restore
all registers and continue original execution.

This generally works fine.  However, now consider what happens when GDB attempts
to do exactly that while the process was interrupted during execution of a to-be-
restarted system call:  do_signal is called with the syscall flag set; it calls
get_signal_to_deliver, at which point the debugger takes over and changes the PC
to point to a completely different place.  Now get_signal_to_deliver returns
without a signal to deliver; but now do_signal decides it should be restarting
a system call, and decrements the PC by 2 or 4 -- so it now points to 2 or 4
bytes before the function GDB wants to call -- which leads to a subsequent crash.

To fix this problem, two things need to be supported:
- do_signal must be able to recognize that get_signal_to_deliver changed the PC
  to a different location, and skip the restart-syscall sequence
- once the debugger has restored all registers at the end of the inferior call
  sequence, do_signal must recognize that *now* it needs to restart the pending
  system call, even though it was now entered from a breakpoint instead of an
  actual svc instruction

This set of issues is solved on other platforms, usually by one of two
mechanisms:

- The status information "do_signal is handling a system call that may need
  restarting" is itself carried in some register that can be accessed via
  ptrace.  This is e.g. on Intel the "orig_eax" register; on Sparc the kernel
  defines a magic extra bit in the flags register for this purpose.
  This allows GDB to manage that state: reset it when doing an inferior call,
  and restore it after the call is finished.

- On s390, do_signal transparently handles this problem without requiring
  GDB interaction, by performing system call restarting in the following
  way: first, adjust the PC as necessary for restarting the call.  Then,
  call get_signal_to_deliver; and finally just continue execution at the
  PC.  This way, if GDB does not change the PC, everything is as before.
  If GDB *does* change the PC, execution will simply continue there --
  and once GDB restores the PC it saved at that point, it will automatically
  point to the *restarted* system call.  (There is the minor twist how to
  handle system calls that do *not* need restarting -- do_signal will undo
  the PC change in this case, after get_signal_to_deliver has returned, and
  only if ptrace did not change the PC during that call.)

Because there does not appear to be any obvious register to carry the
syscall-restart information on ARM, we'd either have to introduce a new
artificial ptrace register just for that purpose, or else handle the issue
transparently like on s390.  The patch below implements the second option;
using this patch makes the interrupt.exp test cases pass on ARM, with no
regression in the GDB test suite otherwise.

Cc: patches@linaro.org
Signed-off-by: Ulrich Weigand <ulrich.weigand@linaro.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12 10:52:00 +01:00
Victor Boivie
4394c12442 ARM: 6893/1: Allow for kernel command line concatenation
This patch allows the provided CONFIG_CMDLINE to be concatenated
with the one provided by the boot loader. This is useful to
merge the static values defined in CONFIG_CMDLINE with the
boot loader's (possibly) more dynamic values, such as startup
reasons and more.

Signed-off-by: Victor Boivie <victor.boivie@sonyericsson.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonyericsson.com>
Signed-off-by: Oskar Andero <oskar.andero@sonyericsson.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12 10:13:22 +01:00
Ingo Molnar
9cb5baba5e Merge commit 'v2.6.39-rc7' into sched/core 2011-05-12 09:36:18 +02:00
Ingo Molnar
98bb318864 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2011-05-04 20:33:42 +02:00
Dan Rosenberg
0f22072ab5 ARM: 6891/1: prevent heap corruption in OABI semtimedop
When CONFIG_OABI_COMPAT is set, the wrapper for semtimedop does not
bound the nsops argument.  A sufficiently large value will cause an
integer overflow in allocation size, followed by copying too much data
into the allocated buffer.  Fix this by restricting nsops to SEMOPM.
Untested.

Cc: stable@kernel.org
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-29 15:53:14 +01:00
Russell King
408133e9dc Merge branch 'kprobes' of git://git.linaro.org/people/nico/linux into fixes 2011-04-29 11:02:45 +01:00
Jon Medhurst
cdc2536115 ARM: kprobes: Tidy-up kprobes-decode.c
- Remove coding standard violations reported by checkpatch.pl
- Delete comment about handling of conditional branches which is no
  longer true.
- Delete comment at end of file which lists all ARM instructions. This
  duplicates data available in the ARM ARM and seems like an
  unnecessary maintenance burden to keep this up to date and accurate.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
9425493078 ARM: kprobes: Add emulation of hint instructions like NOP and WFI
Being able to probe NOP instructions is useful for hard-coding probeable
locations and is used by the kprobes test code.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
20e8155e24 ARM: kprobes: Add emulation of SBFX, UBFX, BFI and BFC instructions
These bit field manipulation instructions occur several thousand
times in an ARMv7 kernel.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:00 -04:00
Jon Medhurst
c9836777d5 ARM: kprobes: Add emulation of MOVW and MOVT instructions
The MOVW and MOVT instructions account for approximately 7% of all
instructions in a ARMv7 kernel as GCC uses them instead of a literal
pool.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f704a6e25b ARM: kprobes: Reject probing of undefined data processing instructions
The instruction decoding in space_cccc_000x needs to reject probing of
instructions with undefined patterns as they may in future become
defined and then emulated faultily - as has already happened with the
SMC instruction.

This fix is achieved by testing for the instruction patterns we want to
probe and making the the default fall-through paths reject probes. This
also allows us to remove some explicit tests for instructions that we
wish to reject, as that is now the default action.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
72c2bab2be ARM: kprobes: Remove redundant code in space_1111
The tests to explicitly reject probing CPS, RFE and SRS instructions
are redundant as the default case is now to reject undecoded patterns.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
41713d1396 ARM: kprobes: Fix emulation of PLD instructions
The PLD instructions wasn't being decoded correctly and the emulation
code wasn't adjusting PC correctly.

As the PLD instruction is only a performance hint we emulate it as a
simple nop, and we can broaden the instruction decoding to take into
account newer PLI and PLDW instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f0aeb8bff0 ARM: kprobes: Reject probing of SETEND instructions
The emulation of SETEND was broken as it changed the endianess for
the running kprobes handling code. Rather than adding a new simulation
routine to fix this we'll just reject probing of SETEND as these should
be very rare in the kernel.

Note, the function emulate_none is now unused but it is left in the
source code as future patches will use it.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
ac211c6994 ARM: kprobes: Consolidate stub decoding functions
Following the change to remove support for coprocessor instructions
we are left with three stub functions which can be consolidated.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
fa1a03b429 ARM: kprobes: Reject probing of all coprocessor instructions
The kernel doesn't currently support VFP or Neon code, and probing of
code with CP15 operations is fraught with bad consequences. Therefore we
don't need the ability to probe coprocessor instructions and the code to
support this can be removed.

The removed code also had at least two bugs:
 - MRC into R15 should set CPSR not trash PC
 - LDC and STC which use PC as base register needed the address offset by 8

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
c6e4ae3291 ARM: kprobes: Fix emulation of USAD8 instructions
The USAD8 instruction wasn't being explicitly decoded leading
to the incorrect emulation routine being called. It can be correctly
decoded in the same way as the signed multiply instructions so we move
the decoding there.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
038c3839c9 ARM: kprobes: Fix emulation of SMUAD, SMUSD and SMMUL instructions
The signed multiply instructions were being decoded incorrectly.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
8dd7cfbed8 ARM: kprobes: Fix emulation of SXTB16, SXTB, SXTH, UXTB16, UXTB and UXTH instructions
These sign extension instructions are encoded as extend-and-add
instructions where the register to add is specified as r15. The decoding
routines weren't checking for this and were using the incorrect
emulation code, giving incorrect results.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
780b5c1162 ARM: kprobes: Reject probing of undefined media instructions
The instructions space for media instructions contains some undefined
patterns. We need to reject probing of these because they may in future
become defined and the kprobes code may then emulate them faultily.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
0e384ed164 ARM: kprobes: Add emulation of RBIT instruction
The v6T2 RBIT instruction was accidentally being emulated correctly,
this patch adds correct decoding for the instruction.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
81ff5720b9 ARM: kprobes: Reject probing of LDRB instructions which load PC
These instructions are specified as UNPREDICTABLE.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
5c6b76fc7d ARM: kprobes: Fix emulation of LDRD and STRD instructions
The decoding of these instructions got the register indexed and
immediate indexed forms the wrong way around, causing incorrect
emulation.

Instructions like "LDRD Rx, [Rx]" were corrupting Rx because the base
register writeback was being performed unconditionally, overwriting the
value just loaded from memory. The fix is to only writeback the base
register when that form of the instruction is used. Note, now that we
reject probing writeback with PC the emulation code doesn't need the
check rn!=15.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
54823accfc ARM: kprobes: Reject probing of LDR/STR instructions which update PC unpredictably
Using PC as an base register with writeback is UNPREDICTABLE, as is non
word-sized loads or stores of PC. (We only really care about preventing
loads to PC but it keeps the code simpler if we also exclude stores.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
6823fc85fc ARM: kprobes: Fix emulation of LDRH, STRH, LDRSB and LDRSH instructions
The decoding of these instructions got the register indexed and
immediate indexed forms the wrong way around, causing incorrect
emulation.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
ec58d7f237 ARM: kprobes: Reject probing of STREX and LDREX instructions
The emulation code for STREX and LDREX instructions is faulty, however,
rather than attempting to fix this we reject probes of these
instructions. We do this because they can never succeed in gaining
exclusive access as the exception framework clears the exclusivity
monitor when a probes breakpoint is hit. (This is a general problem
when probing all instructions executing between a LDREX and its
corresponding STREX and can lead to infinite retry loops.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
ba48d40713 ARM: kprobes: Reject probing of undefined multiply instructions
The instructions space for 'Multiply and multiply-accumulate'
instructions contains some undefined patterns. We need to reject
probing of these because they may in future become defined and the
kprobes code may then emulate them faultily.

This has already happened with the new MLS instruction which this patch
also adds correct decoding for as well as tightening up other decoding
tests. (Before this patch the wrong emulation routine was being called
for MLS though it still produced correct results.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
75539aea4c ARM: kprobes: Fix error in comment
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
983ebd9365 ARM: kprobes: Reject probing of instructions which write to PC unpredictably.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:55 -04:00
Jon Medhurst
c412aba2a1 ARM: kprobes: Fix emulation of MRS instruction
The MRS instruction should set mode and interrupt bits in the read value
so it is simpler to use a new simulation routine (simulate_mrs) rather
than some modified emulation.

prep_emulate_rd12 is now unused and removed.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:55 -04:00
Jon Medhurst
51468ea91e ARM: kprobes: Reject probing MRS instructions which read SPSR
We need to reject probing of instructions which read SPSR because
we can't handle this as the value in SPSR is lost when the exception
handler for the probe breakpoint first runs.

This patch also fixes the bitmask for MRS instructions decoding to
include checking bits 5-7.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:55 -04:00
Jon Medhurst
896a74e19d ARM: kprobes: Fix emulation of Data-processing (immediate) instructions
Emulation of instructions like "ADD rd, rn, #<const>" would result in a
corrupted value for rd.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:55 -04:00
Jon Medhurst
ad111ce466 ARM: kprobes: Fix emulation of CMP, CMN, TST and TEQ instructions.
Probing these instructions was corrupting R0 because the emulation code
didn't account for the fact that they don't write a result to a
register.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:55 -04:00
Jon Medhurst
a539f5d46c ARM: kprobes: Remove redundant condition checks from simulation routines
Now we have the framework code handling conditionally executed
instructions we can remove redundant checks in individual simulation
routines.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:54 -04:00
Jon Medhurst
073090cb70 ARM: kprobes: Fix probing of conditionally executed instructions
When a kprobe is placed onto conditionally executed ARM instructions,
many of the emulation routines used to single step them produce corrupt
register results. Rather than fix all of these cases we modify the
framework which calls them to test the relevant condition flags and, if
the test fails, skip calling the emulation code.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:54 -04:00
Viktor Rosendahl
cf3cc1aa9b kprobes/arm: Fix ldrd/strd emulation
Currently emulate_ldrd and emulate_strd don't even have the adjustment
of the PC value, so in case of Rn == PC, it will not update the PC
incorrectly but instead load/store from the wrong address.  Let's add
both the adjustment of the PC value and the check for PC == PC.

Signed-off-by: Viktor Rosendahl <viktor.rosendahl@nokia.com>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:54 -04:00
Stephen Boyd
a8d2518c2a ARM: 6887/1: Mark broadcast_timer_setup() __cpuinit
This function is only called by percpu_timer_setup() which is
also __cpuinit marked. Thus it's safe to mark this function as
__cpuinit as well.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-27 22:02:47 +01:00
Sonny Rao
860ad7823f ARM: 6884/1: Fix infinite loop in ARM user perf_event backtrace code
The ARM user backtrace code can get into an infinite loop if it
runs into an invalid stack frame which points back to itself.
This situation has been observed in practice.  Fix it by capping
the number of entries in the backtrace.  This is also what other
architectures do in their backtrace code.

Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-27 22:02:46 +01:00