1443 Commits

Author SHA1 Message Date
Russell King
78359cb86b ARM: CPU hotplug: ensure we migrate all IRQs off a downed CPU
Our selection of interrupts to consider for IRQ migration is sub-
standard.  We were potentially including per-CPU interrupts in our
migration strategy, but omitting chained interrupts.  This caused
some interrupts to remain on a downed CPU.

We were also trying to migrate interrupts which were not migratable,
resulting in an OOPS.

Instead, iterate over all interrupts, skipping per-CPU interrupts
or interrupts whose affinity does not include the downed CPU, and
attempt to set the affinity for every one else if their chip
implements irq_set_affinity().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-21 15:14:21 +01:00
Russell King
ca15af19ac ARM: CPU hotplug: pass in proper affinity mask on IRQ migration
Now that the GIC takes care of selecting a target interrupt from the
affinity mask, we don't need all this complexity in the core code
anymore.  Just detect when we need to break affinity.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-21 15:07:56 +01:00
Russell King
2ef75701d1 ARM: CPU hotplug: fix abuse of irqdesc->node
irqdesc's node member is supposed to mark the numa node number for the
interrupt.  Our use of it is non-standard.  Remove this, replacing the
functionality with a test of the affinity mask.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-21 15:00:27 +01:00
Dave Martin
540b573875 ARM: 6999/1: head, zImage: Always Enter the kernel in ARM state
Currently, the documented kernel entry requirements are not
explicit about whether the kernel should be entered in ARM or
Thumb, leading to an ambiguitity about how to enter Thumb-2
kernels.  As a result, the kernel is reliant on the zImage
decompressor to enter the kernel proper in the correct instruction
set state.

This patch changes the boot entry protocol for head.S and Image to
be the same as for zImage: in all cases, the kernel is now entered
in ARM.

Documentation/arm/Booting is updated to reflect this new policy.

A different rule will be needed for Cortex-M class CPUs as and when
support for those lands in mainline, since these CPUs don't support
the ARM instruction set at all: a note is added to the effect that
the kernel must be entered in Thumb on such systems.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-19 12:00:53 +01:00
Russell King
07f1c295de Merge branch 'dma' of http://git.linaro.org/git/people/nico/linux into devel-stable 2011-07-18 23:00:42 +01:00
Nicolas Pitre
4fddcaebb9 ARM: add dma_zone_size to the machine_desc structure
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-18 15:29:57 -04:00
Arnd Bergmann
4d09a93886 Merge branches 'cns3xxx/devel', 'davinci/devel', 'imx/devel', 'lpc32xx/devel', 'pxa/devel', 'tegra/devel' and 'stericsson/master' of git+ssh://master.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc into next/devel 2011-07-17 21:31:38 +02:00
Russell King
4aa96ccf9e Merge branch 'kprobes-thumb' of git://git.yxit.co.uk/linux into devel-stable 2011-07-15 10:06:42 +01:00
Jon Medhurst
8f2ffa00fb ARM: kprobes: Remove now unused code
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:51 +00:00
Jon Medhurst
0239269db6 ARM: kprobes: Decode ARM preload (immediate) instructions
These were missing from the previous implementation.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:51 +00:00
Jon Medhurst
465f1ea595 ARM: kprobes: Reject probing of unprivileged load and store instructions
These occur extremely rarely in the kernel and writing test cases for
them is difficult.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:51 +00:00
Jon Medhurst
711bf10633 ARM: kprobes: Use new versions of emulate_ldr() and emulate_str()
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:51 +00:00
Jon Medhurst
3c48fbb147 ARM: kprobes: Add new versions of emulate_ldr() and emulate_str()
These use the register calling conventions required by the new decoding
table framework for calling simulated instructions.

We rename the old versions of these functions to *_old for now.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
12ce5d3388 ARM: kprobes: Add emulate_rdlo12rdhi16rn0rm8_rwflags_nopc()
This is the emulation function for the instruction format used by the
ARM multiply long instructions. It replaces use of
prep_emulate_rdhi16rdlo12rs8rm0_wflags().

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
c82584ebdf ARM: kprobes: Add emulate_rd12rm0_noflags_nopc()
This is the emulation function for the instruction format used by the
ARM bit-field manipulation instructions.

Various other instruction forms can also make use of this and it is used
to replace use of prep_emulate_rd12{rm0}{_modify}

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
35fab77469 ARM: kprobes: Replace use of prep_emulate_rd12rn16rm0_wflags()
These can now use emulate_rd12rn16rm0_rwflags_nopc().

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
6091dfae4f ARM: kprobes: Add emulate_rd16rn12rm0rs8_rwflags_nopc()
This is the emulation function for the instruction format used by the
ARM multiply-accumulate instructions. These don't allow use of PC so we
don't have to add special cases for this.

This function is used to replace use of prep_emulate_rd16rs8rm0_wflags
and prep_emulate_rd16rn12rs8rm0_wflags.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
e9a92859e9 ARM: kprobes: Migrate remaining instruction decoding functions to tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
0d32e7d11b ARM: kprobes: Migrate ARM space_cccc_100x to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:50 +00:00
Jon Medhurst
56d8fbddc2 ARM: kprobes: Migrate ARM space_cccc_01xx to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
ad2e81a78d ARM: kprobes: Migrate ARM space_cccc_0111__1 to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
2ce5d03307 ARM: kprobes: Migrate ARM space_cccc_0110__1 to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
0e44e9a0fa ARM: kprobes: Add emulate_rd12rn16rm0_rwflags_nopc()
This is the emulation function for the instruction format used by the
ARM media instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
c038f3af50 ARM: kprobes: Migrate ARM space_cccc_001x to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
75f115c087 ARM: kprobes: Migrate ARM space_cccc_000x to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
6c8a192929 ARM: kprobes: Migrate ARM LDRD and STRD to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:49 +00:00
Jon Medhurst
8723942f7b ARM: kprobes: Add emulate_ldrdstrd()
This is an emulation function for the LDRD and STRD instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
3535a89ab2 ARM: kprobes: Migrate ARM data-processing (register) instructions to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
9f596e5126 ARM: kprobes: Add emulate_rd12rn16rm0rs8_rwflags()
This is the emulation function for the instruction format used by the
ARM data-processing instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
7be7ee2d29 ARM: kprobes: Add BLX macro
This is for use by inline assembler which will be added to kprobes-arm.c
It saves memory when used on newer ARM architectures and also provides
correct interworking should ARM probes be required on Thumb kernels in
the future.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
df4fa1f8dd ARM: kprobes: Add alu_write_pc()
This writes a new value to PC which was obtained as the result of an ARM
ALU instruction. For ARMv7 and later this performs interworking.

On ARM kernels we shouldn't encounter any ALU instructions trying to
switch to Thumb mode so support for this isn't strictly necessary.
However, the approach taken in all other instruction decoding is for us
to avoid unpredictable modification of the PC for security reasons. This
is usually achieved by rejecting insertion of probes on problematic
instruction, but for ALU instructions we can't do this as it depends on
the contents of the CPU registers at the time the probe is hit. So, as
we require some form of run-time checking to trap undesirable PC
modification, we may as well simulate the instructions correctly, i.e.
in the way they would behave in the absence of a probe.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
9a5c1284a3 ARM: kprobes: Migrate ARM space_1111 to decoding tables
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
bb1085f827 ARM: kprobes: Decode 32-bit Thumb multiply and absolute difference instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:48 +00:00
Jon Medhurst
231fb150c6 ARM: kprobes: Decode 32-bit Thumb long multiply and divide instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:47 +00:00
Jon Medhurst
31656c1a9a ARM: kprobes: Decode 32-bit Thumb data-processing (register) instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:47 +00:00
Jon Medhurst
d691023b62 ARM: kprobes: Decode 32-bit Thumb load/store single data item instructions
We will reject probing of unprivileged load and store instructions.
These rarely occur and writing test cases for them is difficult.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:47 +00:00
Jon Medhurst
46009cc5c5 ARM: kprobes: Decode 32-bit Thumb memory hint instructions
We'll treat the preload instructions as nops as they are just
performance hints.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:47 +00:00
Jon Medhurst
6a0d1a1c56 ARM: kprobes: Reject 32-bit Thumb coprocessor and SIMD instructions
The kernel doesn't currently support VFP or Neon code, and probing of
code with CP15 operations is fraught with bad consequences. So we will
just reject probing these instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:47 +00:00
Jon Medhurst
ce715c772f ARM: kprobes: Decode 32-bit Thumb branch instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
b06f3ee34d ARM: kprobes: Decode 32-bit miscellaneous control instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
7848786a7a ARM: kprobes: Decode 32-bit Thumb data-processing (plain binary immediate) instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
2fcaf7e758 ARM: kprobes: Decode 32-bit Thumb data-processing (modified immediate) instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
080e001326 ARM: kprobes: Decode 32-bit Thumb data-processing (shifted register) instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
dd212bd3cb ARM: kprobes: Decode 32-bit Thumb table branch instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
b48354d358 ARM: kprobes: Decode 32-bit Thumb load/store dual and load/store exclusive instructions
We reject probing of load/store exclusive instructions because any
emulation routine could never succeed in gaining exclusive access as the
exception framework clears the exclusivity monitor when a probes
breakpoint is hit.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:46 +00:00
Jon Medhurst
eaf1d06500 ARM: kprobes: Decode 32-bit Thumb load/store multiple instructions
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:45 +00:00
Jon Medhurst
3d4a99785a ARM: kprobes: Optimise emulation of LDM and STM
This patch improves the performance of LDM and STM instruction
emulation. This is desirable because.

- jprobes and kretprobes probe the first instruction in a function and,
  when the frame pointer is omitted, this instruction is often a STM
  used to push registers onto the stack.

- The STM and LDM instructions are common in the body and tail of
  functions.

- At the same time as being a common instruction form, they also have
  one of the slowest and most complicated simulation routines.

The approach taken to optimisation is to use emulation rather than
simulation, that is, a modified form of the instruction is run with
an appropriate register context.

Benchmarking on an OMAP3530 shows the optimised emulation is between 2
and 3 times faster than the simulation routines. On a Kirkwood based
device the relative performance was very significantly better than this.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:45 +00:00
Jon Medhurst
235a4ce79f ARM: kprobes: Add common decoding function for LDM and STM
The encoding of these instructions is substantially the same for both
ARM and Thumb, so we can have common decoding and simulation functions.

This patch moves the simulation functions from kprobes-arm.c to
kprobes-common.c. It also adds a new simulation function
(simulate_ldm1_pc) for the case where we load into PC because this may
need to interwork.

The instruction decoding is done by a custom function
(kprobe_decode_ldmstm) rather than just relying on decoding table
entries because we will later be adding optimisation code.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:45 +00:00
Jon Medhurst
263e368a2f ARM: kprobes: Add load_write_pc()
This writes a value to PC which was obtained as the result of a
LDR or LDM instruction. For ARMv5T and later this must perform
interworking.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:45 +00:00
Jon Medhurst
f39ca8b488 ARM: kprobes: Decode 32-bit Thumb hint instructions
For hints which may have observable effects, like SEV (send event), we
use kprobe_emulate_none which emulates the hint by executing the
original instruction.

For NOP we simulate the instruction using kprobe_simulate_nop, which
does nothing. As probes execute with interrupts disabled this is also
used for hints which may block for an indefinite time, like WFE (wait
for event).

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:45 +00:00