diff options
| -rw-r--r-- | arch/arm/kernel/kprobes-thumb.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-thumb.c b/arch/arm/kernel/kprobes-thumb.c index e0289493b4c6..e496948fefac 100644 --- a/arch/arm/kernel/kprobes-thumb.c +++ b/arch/arm/kernel/kprobes-thumb.c @@ -110,6 +110,37 @@ t16_simulate_cbz(struct kprobe *p, struct pt_regs *regs) } } +static void __kprobes +t16_simulate_it(struct kprobe *p, struct pt_regs *regs) +{ + /* + * The 8 IT state bits are split into two parts in CPSR: + * ITSTATE<1:0> are in CPSR<26:25> + * ITSTATE<7:2> are in CPSR<15:10> + * The new IT state is in the lower byte of insn. + */ + kprobe_opcode_t insn = p->opcode; + unsigned long cpsr = regs->ARM_cpsr; + cpsr &= ~PSR_IT_MASK; + cpsr |= (insn & 0xfc) << 8; + cpsr |= (insn & 0x03) << 25; + regs->ARM_cpsr = cpsr; +} + +static void __kprobes +t16_singlestep_it(struct kprobe *p, struct pt_regs *regs) +{ + regs->ARM_pc += 2; + t16_simulate_it(p, regs); +} + +static enum kprobe_insn __kprobes +t16_decode_it(kprobe_opcode_t insn, struct arch_specific_insn *asi) +{ + asi->insn_singlestep = t16_singlestep_it; + return INSN_GOOD_NO_SLOT; +} + static unsigned long __kprobes t16_emulate_loregs(struct kprobe *p, struct pt_regs *regs) { @@ -310,6 +341,8 @@ static const union decode_item t16_table_1011[] = { DECODE_SIMULATE (0xffcf, 0xbf00, kprobe_simulate_nop), /* Unassigned hints 1011 1111 xxxx 0000 */ DECODE_REJECT (0xff0f, 0xbf00), + /* IT 1011 1111 xxxx xxxx */ + DECODE_CUSTOM (0xff00, 0xbf00, t16_decode_it), DECODE_END }; |