[PATCH 01/10] objtool: Change arch_decode_instruction() signature
From: Peter Zijlstra
Date: Wed Feb 08 2023 - 12:24:13 EST
In preparation to changing struct instruction around a bit, avoid
passing it's members by pointer and instead pass the whole thing.
A cleanup in it's own right too.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
tools/objtool/arch/powerpc/decode.c | 22 +++----
tools/objtool/arch/x86/decode.c | 105 +++++++++++++++++------------------
tools/objtool/check.c | 4 -
tools/objtool/include/objtool/arch.h | 4 -
4 files changed, 64 insertions(+), 71 deletions(-)
--- a/tools/objtool/arch/powerpc/decode.c
+++ b/tools/objtool/arch/powerpc/decode.c
@@ -41,38 +41,36 @@ const char *arch_ret_insn(int len)
int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
unsigned long offset, unsigned int maxlen,
- unsigned int *len, enum insn_type *type,
- unsigned long *immediate,
- struct list_head *ops_list)
+ struct instruction *insn)
{
unsigned int opcode;
enum insn_type typ;
unsigned long imm;
- u32 insn;
+ u32 ins;
- insn = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset));
- opcode = insn >> 26;
+ ins = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset));
+ opcode = ins >> 26;
typ = INSN_OTHER;
imm = 0;
switch (opcode) {
case 18: /* b[l][a] */
- if ((insn & 3) == 1) /* bl */
+ if ((ins & 3) == 1) /* bl */
typ = INSN_CALL;
- imm = insn & 0x3fffffc;
+ imm = ins & 0x3fffffc;
if (imm & 0x2000000)
imm -= 0x4000000;
break;
}
if (opcode == 1)
- *len = 8;
+ insn->len = 8;
else
- *len = 4;
+ insn->len = 4;
- *type = typ;
- *immediate = imm;
+ insn->type = typ;
+ insn->immediate = imm;
return 0;
}
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -146,12 +146,11 @@ static bool has_notrack_prefix(struct in
int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
unsigned long offset, unsigned int maxlen,
- unsigned int *len, enum insn_type *type,
- unsigned long *immediate,
- struct list_head *ops_list)
+ struct instruction *insn)
{
+ struct list_head *ops_list = &insn->stack_ops;
const struct elf *elf = file->elf;
- struct insn insn;
+ struct insn ins;
int x86_64, ret;
unsigned char op1, op2, op3, prefix,
rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, rex_x = 0,
@@ -165,42 +164,42 @@ int arch_decode_instruction(struct objto
if (x86_64 == -1)
return -1;
- ret = insn_decode(&insn, sec->data->d_buf + offset, maxlen,
+ ret = insn_decode(&ins, sec->data->d_buf + offset, maxlen,
x86_64 ? INSN_MODE_64 : INSN_MODE_32);
if (ret < 0) {
WARN("can't decode instruction at %s:0x%lx", sec->name, offset);
return -1;
}
- *len = insn.length;
- *type = INSN_OTHER;
+ insn->len = ins.length;
+ insn->type = INSN_OTHER;
- if (insn.vex_prefix.nbytes)
+ if (ins.vex_prefix.nbytes)
return 0;
- prefix = insn.prefixes.bytes[0];
+ prefix = ins.prefixes.bytes[0];
- op1 = insn.opcode.bytes[0];
- op2 = insn.opcode.bytes[1];
- op3 = insn.opcode.bytes[2];
+ op1 = ins.opcode.bytes[0];
+ op2 = ins.opcode.bytes[1];
+ op3 = ins.opcode.bytes[2];
- if (insn.rex_prefix.nbytes) {
- rex = insn.rex_prefix.bytes[0];
+ if (ins.rex_prefix.nbytes) {
+ rex = ins.rex_prefix.bytes[0];
rex_w = X86_REX_W(rex) >> 3;
rex_r = X86_REX_R(rex) >> 2;
rex_x = X86_REX_X(rex) >> 1;
rex_b = X86_REX_B(rex);
}
- if (insn.modrm.nbytes) {
- modrm = insn.modrm.bytes[0];
+ if (ins.modrm.nbytes) {
+ modrm = ins.modrm.bytes[0];
modrm_mod = X86_MODRM_MOD(modrm);
modrm_reg = X86_MODRM_REG(modrm) + 8*rex_r;
modrm_rm = X86_MODRM_RM(modrm) + 8*rex_b;
}
- if (insn.sib.nbytes) {
- sib = insn.sib.bytes[0];
+ if (ins.sib.nbytes) {
+ sib = ins.sib.bytes[0];
/* sib_scale = X86_SIB_SCALE(sib); */
sib_index = X86_SIB_INDEX(sib) + 8*rex_x;
sib_base = X86_SIB_BASE(sib) + 8*rex_b;
@@ -254,7 +253,7 @@ int arch_decode_instruction(struct objto
break;
case 0x70 ... 0x7f:
- *type = INSN_JUMP_CONDITIONAL;
+ insn->type = INSN_JUMP_CONDITIONAL;
break;
case 0x80 ... 0x83:
@@ -278,7 +277,7 @@ int arch_decode_instruction(struct objto
if (!rm_is_reg(CFI_SP))
break;
- imm = insn.immediate.value;
+ imm = ins.immediate.value;
if (op1 & 2) { /* sign extend */
if (op1 & 1) { /* imm32 */
imm <<= 32;
@@ -309,7 +308,7 @@ int arch_decode_instruction(struct objto
ADD_OP(op) {
op->src.type = OP_SRC_AND;
op->src.reg = CFI_SP;
- op->src.offset = insn.immediate.value;
+ op->src.offset = ins.immediate.value;
op->dest.type = OP_DEST_REG;
op->dest.reg = CFI_SP;
}
@@ -356,7 +355,7 @@ int arch_decode_instruction(struct objto
op->src.reg = CFI_SP;
op->dest.type = OP_DEST_REG_INDIRECT;
op->dest.reg = modrm_rm;
- op->dest.offset = insn.displacement.value;
+ op->dest.offset = ins.displacement.value;
}
break;
}
@@ -389,7 +388,7 @@ int arch_decode_instruction(struct objto
op->src.reg = modrm_reg;
op->dest.type = OP_DEST_REG_INDIRECT;
op->dest.reg = CFI_BP;
- op->dest.offset = insn.displacement.value;
+ op->dest.offset = ins.displacement.value;
}
break;
}
@@ -402,7 +401,7 @@ int arch_decode_instruction(struct objto
op->src.reg = modrm_reg;
op->dest.type = OP_DEST_REG_INDIRECT;
op->dest.reg = CFI_SP;
- op->dest.offset = insn.displacement.value;
+ op->dest.offset = ins.displacement.value;
}
break;
}
@@ -419,7 +418,7 @@ int arch_decode_instruction(struct objto
ADD_OP(op) {
op->src.type = OP_SRC_REG_INDIRECT;
op->src.reg = CFI_BP;
- op->src.offset = insn.displacement.value;
+ op->src.offset = ins.displacement.value;
op->dest.type = OP_DEST_REG;
op->dest.reg = modrm_reg;
}
@@ -432,7 +431,7 @@ int arch_decode_instruction(struct objto
ADD_OP(op) {
op->src.type = OP_SRC_REG_INDIRECT;
op->src.reg = CFI_SP;
- op->src.offset = insn.displacement.value;
+ op->src.offset = ins.displacement.value;
op->dest.type = OP_DEST_REG;
op->dest.reg = modrm_reg;
}
@@ -464,7 +463,7 @@ int arch_decode_instruction(struct objto
/* lea disp(%src), %dst */
ADD_OP(op) {
- op->src.offset = insn.displacement.value;
+ op->src.offset = ins.displacement.value;
if (!op->src.offset) {
/* lea (%src), %dst */
op->src.type = OP_SRC_REG;
@@ -487,7 +486,7 @@ int arch_decode_instruction(struct objto
break;
case 0x90:
- *type = INSN_NOP;
+ insn->type = INSN_NOP;
break;
case 0x9c:
@@ -511,39 +510,39 @@ int arch_decode_instruction(struct objto
if (op2 == 0x01) {
if (modrm == 0xca)
- *type = INSN_CLAC;
+ insn->type = INSN_CLAC;
else if (modrm == 0xcb)
- *type = INSN_STAC;
+ insn->type = INSN_STAC;
} else if (op2 >= 0x80 && op2 <= 0x8f) {
- *type = INSN_JUMP_CONDITIONAL;
+ insn->type = INSN_JUMP_CONDITIONAL;
} else if (op2 == 0x05 || op2 == 0x07 || op2 == 0x34 ||
op2 == 0x35) {
/* sysenter, sysret */
- *type = INSN_CONTEXT_SWITCH;
+ insn->type = INSN_CONTEXT_SWITCH;
} else if (op2 == 0x0b || op2 == 0xb9) {
/* ud2 */
- *type = INSN_BUG;
+ insn->type = INSN_BUG;
} else if (op2 == 0x0d || op2 == 0x1f) {
/* nopl/nopw */
- *type = INSN_NOP;
+ insn->type = INSN_NOP;
} else if (op2 == 0x1e) {
if (prefix == 0xf3 && (modrm == 0xfa || modrm == 0xfb))
- *type = INSN_ENDBR;
+ insn->type = INSN_ENDBR;
} else if (op2 == 0x38 && op3 == 0xf8) {
- if (insn.prefixes.nbytes == 1 &&
- insn.prefixes.bytes[0] == 0xf2) {
+ if (ins.prefixes.nbytes == 1 &&
+ ins.prefixes.bytes[0] == 0xf2) {
/* ENQCMD cannot be used in the kernel. */
WARN("ENQCMD instruction at %s:%lx", sec->name,
offset);
@@ -591,29 +590,29 @@ int arch_decode_instruction(struct objto
case 0xcc:
/* int3 */
- *type = INSN_TRAP;
+ insn->type = INSN_TRAP;
break;
case 0xe3:
/* jecxz/jrcxz */
- *type = INSN_JUMP_CONDITIONAL;
+ insn->type = INSN_JUMP_CONDITIONAL;
break;
case 0xe9:
case 0xeb:
- *type = INSN_JUMP_UNCONDITIONAL;
+ insn->type = INSN_JUMP_UNCONDITIONAL;
break;
case 0xc2:
case 0xc3:
- *type = INSN_RETURN;
+ insn->type = INSN_RETURN;
break;
case 0xc7: /* mov imm, r/m */
if (!opts.noinstr)
break;
- if (insn.length == 3+4+4 && !strncmp(sec->name, ".init.text", 10)) {
+ if (ins.length == 3+4+4 && !strncmp(sec->name, ".init.text", 10)) {
struct reloc *immr, *disp;
struct symbol *func;
int idx;
@@ -661,17 +660,17 @@ int arch_decode_instruction(struct objto
case 0xca: /* retf */
case 0xcb: /* retf */
- *type = INSN_CONTEXT_SWITCH;
+ insn->type = INSN_CONTEXT_SWITCH;
break;
case 0xe0: /* loopne */
case 0xe1: /* loope */
case 0xe2: /* loop */
- *type = INSN_JUMP_CONDITIONAL;
+ insn->type = INSN_JUMP_CONDITIONAL;
break;
case 0xe8:
- *type = INSN_CALL;
+ insn->type = INSN_CALL;
/*
* For the impact on the stack, a CALL behaves like
* a PUSH of an immediate value (the return address).
@@ -683,30 +682,30 @@ int arch_decode_instruction(struct objto
break;
case 0xfc:
- *type = INSN_CLD;
+ insn->type = INSN_CLD;
break;
case 0xfd:
- *type = INSN_STD;
+ insn->type = INSN_STD;
break;
case 0xff:
if (modrm_reg == 2 || modrm_reg == 3) {
- *type = INSN_CALL_DYNAMIC;
- if (has_notrack_prefix(&insn))
+ insn->type = INSN_CALL_DYNAMIC;
+ if (has_notrack_prefix(&ins))
WARN("notrack prefix found at %s:0x%lx", sec->name, offset);
} else if (modrm_reg == 4) {
- *type = INSN_JUMP_DYNAMIC;
- if (has_notrack_prefix(&insn))
+ insn->type = INSN_JUMP_DYNAMIC;
+ if (has_notrack_prefix(&ins))
WARN("notrack prefix found at %s:0x%lx", sec->name, offset);
} else if (modrm_reg == 5) {
/* jmpf */
- *type = INSN_CONTEXT_SWITCH;
+ insn->type = INSN_CONTEXT_SWITCH;
} else if (modrm_reg == 6) {
@@ -723,7 +722,7 @@ int arch_decode_instruction(struct objto
break;
}
- *immediate = insn.immediate.nbytes ? insn.immediate.value : 0;
+ insn->immediate = ins.immediate.nbytes ? ins.immediate.value : 0;
return 0;
}
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -404,9 +404,7 @@ static int decode_instructions(struct ob
ret = arch_decode_instruction(file, sec, offset,
sec->sh.sh_size - offset,
- &insn->len, &insn->type,
- &insn->immediate,
- &insn->stack_ops);
+ insn);
if (ret)
goto err;
--- a/tools/objtool/include/objtool/arch.h
+++ b/tools/objtool/include/objtool/arch.h
@@ -75,9 +75,7 @@ void arch_initial_func_cfi_state(struct
int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
unsigned long offset, unsigned int maxlen,
- unsigned int *len, enum insn_type *type,
- unsigned long *immediate,
- struct list_head *ops_list);
+ struct instruction *insn);
bool arch_callee_saved_reg(unsigned char reg);