ARM: kprobes: Add Thumb instruction decoding stubs

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>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/arm/kernel/kprobes.h b/arch/arm/kernel/kprobes.h
index 406bb2da7fea..86abfabe83f2 100644
--- a/arch/arm/kernel/kprobes.h
+++ b/arch/arm/kernel/kprobes.h
@@ -29,8 +29,21 @@ enum kprobe_insn {
         INSN_GOOD_NO_SLOT
 };
 
+typedef enum kprobe_insn (kprobe_decode_insn_t)(kprobe_opcode_t,
+                                                struct arch_specific_insn *);
+
+#ifdef CONFIG_THUMB2_KERNEL
+
+enum kprobe_insn thumb16_kprobe_decode_insn(kprobe_opcode_t,
+                                                struct arch_specific_insn *);
+enum kprobe_insn thumb32_kprobe_decode_insn(kprobe_opcode_t,
+                                                struct arch_specific_insn *);
+
+#else /* !CONFIG_THUMB2_KERNEL */
+
 enum kprobe_insn arm_kprobe_decode_insn(kprobe_opcode_t,
                                         struct arch_specific_insn *);
+#endif
 
 void __init arm_kprobe_decode_init(void);