arm64: kprobes instruction simulation support
authorSandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Fri, 8 Jul 2016 16:35:51 +0000 (12:35 -0400)
committerCatalin Marinas <catalin.marinas@arm.com>
Tue, 19 Jul 2016 14:03:21 +0000 (15:03 +0100)
commit39a67d49ba353630d144a8eb775500c041c89e7a
tree8a15a87c630a2710e2acdbcd0a0fc627999276f8
parent888b3c8720e0a4033db09ba2364afde6a4763638
arm64: kprobes instruction simulation support

Kprobes needs simulation of instructions that cannot be stepped
from a different memory location, e.g.: those instructions
that uses PC-relative addressing. In simulation, the behaviour
of the instruction is implemented using a copy of pt_regs.

The following instruction categories are simulated:
 - All branching instructions(conditional, register, and immediate)
 - Literal access instructions(load-literal, adr/adrp)

Conditional execution is limited to branching instructions in
ARM v8. If conditions at PSTATE do not match the condition fields
of opcode, the instruction is effectively NOP.

Thanks to Will Cohen for assorted suggested changes.

Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: William Cohen <wcohen@redhat.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: removed linux/module.h include]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/include/asm/probes.h
arch/arm64/kernel/insn.c
arch/arm64/kernel/probes/Makefile
arch/arm64/kernel/probes/decode-insn.c
arch/arm64/kernel/probes/decode-insn.h
arch/arm64/kernel/probes/kprobes.c
arch/arm64/kernel/probes/simulate-insn.c [new file with mode: 0644]
arch/arm64/kernel/probes/simulate-insn.h [new file with mode: 0644]