summaryrefslogtreecommitdiff
path: root/arch/arm/kernel/kprobes-thumb.c
AgeCommit message (Collapse)Author
2014-04-01ARM: probes: fix instruction fetch order with <asm/opcodes.h>Ben Dooks
If we are running BE8, the data and instruction endianness do not match, so use <asm/opcodes.h> to correctly translate memory accesses into ARM instructions. Acked-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> [taras.kondratiuk@linaro.org: fixed Thumb instruction fetch order] Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
2014-03-18ARM: Make arch_specific_insn a define for new arch_probes_insn structureDavid A. Long
Because the common underlying code for ARM kprobes and uprobes needs to share a common architecrure-specific context structure, and because the generic kprobes include file insists on defining this to a dummy structure when kprobes is not configured, a new common structure is required which can exist when uprobes is configured without kprobes. In this case kprobes will define a dummy structure, but without the define aliasing the two structure tags it will not affect uprobes and the shared probes code. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: Rename the shared kprobes/uprobe return value enumDavid A. Long
Change the name of kprobes_insn to probes_insn so it can be shared between kprobes and uprobes without confusion. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: Change more ARM kprobes symbol names to something more genericDavid A. Long
Change kprobe_emulate_none, kprobe_simulate_nop, and arm_kprobe_decode_init function names to something more appropriate for code being shared outside of the kprobes subsystem. Also, move the new arm_probes_decode_init declaration out of the kprobes.h include file and into the probes.h include file. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: Make the kprobes condition_check symbol names more genericDavid A. Long
In preparation for sharing the ARM kprobes instruction interpreting code with uprobes, make the symbols names less kprobes-specific. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: Remove use of struct kprobe from generic probes codeDavid A. Long
Change the generic ARM probes code to pass in the opcode and architecture-specific structure separately instead of using struct kprobe, so we do not pollute code being used only for uprobes or other non-kprobes instruction interpretation. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: use a function table for determining instruction interpreter actionDavid A. Long
Make the instruction interpreter call back to semantic action functions through a function pointer array provided by the invoker. The interpreter decodes the instructions into groups and uses the group number to index into the supplied array. kprobes and uprobes code will each supply their own array of functions. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2014-03-18ARM: move generic thumb instruction parsing code to new files for use by ↵David A. Long
other feature Move the thumb version of the kprobes instruction parsing code into more generic files from where it can be used by uprobes and possibly other subsystems. The symbol names will be made more generic in a subsequent part of this patchset. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Jon Medhurst <tixy@linaro.org>
2012-06-14ARM: 7423/1: kprobes: run t32_simulate_ldr_literal() without insn slotRabin Vincent
t32_simulate_ldr_literal() can be run without an instruction slot, so it should be using DECODE_SIMULATEX instead of DECODE_EMULATEX. Acked-by: Jon Medhurst <tixy@yxit.co.uk> Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-20ARM: kprobes: Add exports for test codeJon Medhurst
The test code will be using kprobes' internal decoding tables so we need to export these for when then the tests are compiled as a module. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb multiply and absolute difference instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb long multiply and divide instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb data-processing (register) instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb load/store single data item instructionsJon Medhurst
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>
2011-07-13ARM: kprobes: Decode 32-bit Thumb memory hint instructionsJon Medhurst
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>
2011-07-13ARM: kprobes: Reject 32-bit Thumb coprocessor and SIMD instructionsJon Medhurst
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>
2011-07-13ARM: kprobes: Decode 32-bit Thumb branch instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit miscellaneous control instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb data-processing (plain binary immediate) ↵Jon Medhurst
instructions Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb data-processing (modified immediate) ↵Jon Medhurst
instructions Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb data-processing (shifted register) ↵Jon Medhurst
instructions Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb table branch instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb load/store dual and load/store exclusive ↵Jon Medhurst
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>
2011-07-13ARM: kprobes: Decode 32-bit Thumb load/store multiple instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 32-bit Thumb hint instructionsJon Medhurst
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>
2011-07-13ARM: kprobes: Reject 16-bit Thumb SETEND, CPS and BKPT instructionsJon Medhurst
These are very rare and/or problematic to emulate so we will take the easy option and disallow probing them (as does the existing ARM implementation). Rejecting these instructions doesn't actually require any entries in the decoding table as it is the default case for instructions which aren't found. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb branch instructionsJon Medhurst
We previously changed the behaviour of probes so that conditional instructions don't fire when the condition isn't met. For ARM branches, and Thumb branches in IT blocks, this means they don't fire if the branch isn't taken. For consistency, we implement the same for Thumb conditional branch instructions. This involves setting up insn_check_cc to point to the relevant condition checking function. As the emulation routine is only called when this condition passes, it doesn't need to check again and can unconditionally update PC. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Reject 16-bit Thumb SVC and UNDEFINED instructionsJon Medhurst
SVC (SWI) instructions shouldn't occur in kernel code so we don't need to be able to probe them. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb IT instructionJon Medhurst
The normal Thumb singlestepping routine updates the IT state after calling the instruction handler. We don't what this to happen after the IT instruction simulation sets the IT state, therefore we need to provide a custom singlestep routine. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb PUSH and POP instructionsJon Medhurst
These instructions are equivalent to stmdb sp!,{r0-r7,lr} ldmdb sp!,{r0-r7,pc} and we emulate them by transforming them into the 32-bit Thumb instructions stmdb r9!,{r0-r7,r8} ldmdb r9!,{r0-r7,r8} This is simpler, and almost certainly executes faster, than writing simulation functions. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb CBZ and bit manipulation instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb PC- and SP-relative address instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb load and store instructionsJon Medhurst
Most of these instructions only operate on the low registers R0-R7 so they can make use of t16_emulate_loregs_rwflags. The instructions which use SP or PC for addressing have their own simulation functions. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb special data instructionsJon Medhurst
These data-processing instructions operate on the full range of CPU registers, so to simulate them we have to modify the registers used by the instruction. We can't make use of the decoding table framework to do this because the registers aren't encoded cleanly in separate nibbles, therefore we need a custom decode function. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb BX and BLX instructionsJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb data-processing instructionsJon Medhurst
These instructions only operate on the low registers R0-R7, therefore it is possible to emulate them by executing the original instruction unaltered if we restore and save these registers. This is what t16_emulate_loregs does. Some of these instructions don't update the PSR when they execute in an IT block, so there are two flavours of emulation functions: t16_emulate_loregs_{noit}rwflags Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Decode 16-bit Thumb hint instructionsJon Medhurst
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>
2011-07-13ARM: kprobes: Add hooks to override singlestep()Jon Medhurst
When a probe fires we must single-step the instruction which was replaced by a breakpoint. As the steps to do this vary between ARM and Thumb instructions we need a way to customise single-stepping. This is done by adding a new hook called insn_singlestep to arch_specific_insn which is initialised by the instruction decoding functions. These single-step hooks must update PC and call the instruction handler. For Thumb instructions an additional step of updating ITSTATE is needed. We do this after calling the handler because some handlers will need to test if they are running in an IT block. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Add condition code checking to Thumb emulationJon Medhurst
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13ARM: kprobes: Add Thumb instruction decoding stubsJon Medhurst
Extend arch_prepare_kprobe to support probing of Thumb code. For the actual decoding of Thumb instructions, stub functions are added which currently just reject the probe. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>