redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

ARM: Add an emulate flag to the kprobes/uprobes instruction decode functions 

Add an emulate flag into the instruction interpreter, primarily for uprobes
support.

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Jon Medhurst <tixy@linaro.org>
hifive-unleashed-5.1
David A. Long 2014-03-05 21:40:12 -05:00
parent 47e190fafd
commit 602cd2609e
8 changed files with 25 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/arm/kernel/kprobes.c
View File

@ -89,7 +89,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
p->opcode = insn;
p->ainsn.insn = tmp_insn;
switch ((*decode_insn)(insn, &p->ainsn, actions)) {
switch ((*decode_insn)(insn, &p->ainsn, true, actions)) {
case INSN_REJECTED: /* not supported */
return -EINVAL;

1
arch/arm/kernel/kprobes.h
View File

@ -35,6 +35,7 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi,
typedef enum probes_insn (kprobe_decode_insn_t)(probes_opcode_t,
struct arch_specific_insn *,
bool,
const union decode_action *);
#ifdef CONFIG_THUMB2_KERNEL

4
arch/arm/kernel/probes-arm.c
View File

@ -725,10 +725,10 @@ static void __kprobes arm_singlestep(probes_opcode_t insn,
*/
enum probes_insn __kprobes
arm_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_action *actions)
bool emulate, const union decode_action *actions)
{
asi->insn_singlestep = arm_singlestep;
asi->insn_check_cc = probes_condition_checks[insn>>28];
return probes_decode_insn(insn, asi, probes_decode_arm_table, false,
actions);
emulate, actions);
}

2
arch/arm/kernel/probes-arm.h
View File

@ -67,7 +67,7 @@ void __kprobes simulate_mov_ipsp(probes_opcode_t opcode,
extern const union decode_item probes_decode_arm_table[];
enum probes_insn arm_probes_decode_insn(probes_opcode_t,
struct arch_specific_insn *,
struct arch_specific_insn *, bool emulate,
const union decode_action *actions);
#endif

8
arch/arm/kernel/probes-thumb.c
View File

@ -863,20 +863,20 @@ static void __kprobes thumb32_singlestep(probes_opcode_t opcode,
enum probes_insn __kprobes
thumb16_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_action *actions)
bool emulate, const union decode_action *actions)
{
asi->insn_singlestep = thumb16_singlestep;
asi->insn_check_cc = thumb_check_cc;
return probes_decode_insn(insn, asi, probes_decode_thumb16_table, true,
actions);
emulate, actions);
}
enum probes_insn __kprobes
thumb32_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_action *actions)
bool emulate, const union decode_action *actions)
{
asi->insn_singlestep = thumb32_singlestep;
asi->insn_check_cc = thumb_check_cc;
return probes_decode_insn(insn, asi, probes_decode_thumb32_table, true,
actions);
emulate, actions);
}

4
arch/arm/kernel/probes-thumb.h
View File

@ -89,9 +89,9 @@ extern const union decode_item probes_decode_thumb16_table[];
enum probes_insn __kprobes
thumb16_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_action *actions);
bool emulate, const union decode_action *actions);
enum probes_insn __kprobes
thumb32_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_action *actions);
bool emulate, const union decode_action *actions);
#endif

18
arch/arm/kernel/probes.c
View File

@ -257,7 +257,7 @@ set_emulated_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
* non-zero value, the corresponding nibble in pinsn is validated and modified
* according to the type.
*/
static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs)
static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs, bool modify)
{
probes_opcode_t insn = *pinsn;
probes_opcode_t mask = 0xf; /* Start at least significant nibble */
@ -323,7 +323,9 @@ static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs)
insn |= new_bits & mask;
}
*pinsn = insn;
if (modify)
*pinsn = insn;
return true;
reject:
@ -385,13 +387,14 @@ static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
int __kprobes
probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_item *table, bool thumb,
const union decode_action *actions)
bool emulate, const union decode_action *actions)
{
const struct decode_header *h = (struct decode_header *)table;
const struct decode_header *next;
bool matched = false;
insn = prepare_emulated_insn(insn, asi, thumb);
if (emulate)
insn = prepare_emulated_insn(insn, asi, thumb);
for (;; h = next) {
enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
@ -406,7 +409,7 @@ probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
if (!matched && (insn & h->mask.bits) != h->value.bits)
continue;
if (!decode_regs(&insn, regs))
if (!decode_regs(&insn, regs, emulate))
return INSN_REJECTED;
switch (type) {
@ -430,6 +433,11 @@ probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
case DECODE_TYPE_EMULATE: {
struct decode_emulate *d = (struct decode_emulate *)h;
if (!emulate)
return actions[d->handler.action].decoder(insn,
asi, h);
asi->insn_handler = actions[d->handler.action].handler;
set_emulated_insn(insn, asi, thumb);
return INSN_GOOD;

2
arch/arm/kernel/probes.h
View File

@ -401,7 +401,7 @@ probes_insn_handler_t probes_emulate_none;
int __kprobes
probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi,
const union decode_item *table, bool thumb,
const union decode_item *table, bool thumb, bool emulate,
const union decode_action *actions);
#endif