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| author | Jon Medhurst <tixy@yxit.co.uk> | 2011-06-09 15:05:51 +0200 |
|---|---|---|
| committer | Tixy <tixy@medhuaa1.miniserver.com> | 2011-07-13 19:32:42 +0200 |
| commit | e2960317d4581689bf80dbad4d75e7a59f11a3f7 (patch) | |
| tree | 1a80fc69624bd87d1e2393c3a67ce15dc1c17daf | |
| parent | ARM: kprobes: Add hooks to override singlestep() (diff) | |
| download | linux-e2960317d4581689bf80dbad4d75e7a59f11a3f7.tar.xz linux-e2960317d4581689bf80dbad4d75e7a59f11a3f7.zip | |
ARM: kprobes: Extend arch_specific_insn to add pointer to emulated instruction
When we come to emulating Thumb instructions then, to interwork
correctly, the code on in the instruction slot must be invoked with a
function pointer which has the least significant bit set. Rather that
set this by hand in every Thumb emulation function we will add a new
field for this purpose to arch_specific_insn, called insn_fn.
This also enables us to seamlessly share emulation functions between ARM
and Thumb code.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
| -rw-r--r-- | arch/arm/include/asm/kprobes.h | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/kprobes.c | 5 |
2 files changed, 7 insertions, 0 deletions
diff --git a/arch/arm/include/asm/kprobes.h b/arch/arm/include/asm/kprobes.h index 1e9ff56d40c7..feec86768f9c 100644 --- a/arch/arm/include/asm/kprobes.h +++ b/arch/arm/include/asm/kprobes.h @@ -34,6 +34,7 @@ struct kprobe; typedef void (kprobe_insn_handler_t)(struct kprobe *, struct pt_regs *); typedef unsigned long (kprobe_check_cc)(unsigned long); typedef void (kprobe_insn_singlestep_t)(struct kprobe *, struct pt_regs *); +typedef void (kprobe_insn_fn_t)(void); /* Architecture specific copy of original instruction. */ struct arch_specific_insn { @@ -41,6 +42,7 @@ struct arch_specific_insn { kprobe_insn_handler_t *insn_handler; kprobe_check_cc *insn_check_cc; kprobe_insn_singlestep_t *insn_singlestep; + kprobe_insn_fn_t *insn_fn; }; struct prev_kprobe { diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 77b7c6974802..129c1163248b 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -51,6 +51,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) kprobe_opcode_t insn; kprobe_opcode_t tmp_insn[MAX_INSN_SIZE]; unsigned long addr = (unsigned long)p->addr; + bool thumb; kprobe_decode_insn_t *decode_insn; int is; @@ -58,6 +59,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return -EINVAL; #ifdef CONFIG_THUMB2_KERNEL + thumb = true; addr &= ~1; /* Bit 0 would normally be set to indicate Thumb code */ insn = ((u16 *)addr)[0]; if (is_wide_instruction(insn)) { @@ -67,6 +69,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) } else decode_insn = thumb16_kprobe_decode_insn; #else /* !CONFIG_THUMB2_KERNEL */ + thumb = false; if (addr & 0x3) return -EINVAL; insn = *p->addr; @@ -88,6 +91,8 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) p->ainsn.insn[is] = tmp_insn[is]; flush_insns(p->ainsn.insn, sizeof(p->ainsn.insn[0]) * MAX_INSN_SIZE); + p->ainsn.insn_fn = (kprobe_insn_fn_t *) + ((uintptr_t)p->ainsn.insn | thumb); break; case INSN_GOOD_NO_SLOT: /* instruction doesn't need insn slot */ |