mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-11 21:14:07 +08:00
b68b990706
A Clang-built kernel is showing the following warning:
arch/x86/kernel/platform-quirks.o: warning: objtool: x86_early_init_platform_quirks()+0x84: unreachable instruction
That corresponds to this code:
7e: 0f 85 00 00 00 00 jne 84 <x86_early_init_platform_quirks+0x84>
80: R_X86_64_PC32 __x86_indirect_thunk_r11-0x4
84: c3 retq
This is a conditional retpoline sibling call, which is now possible
thanks to retpolines. Objtool hasn't seen that before. It's
incorrectly interpreting the conditional jump as an unconditional
dynamic jump.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/30d4c758b267ef487fb97e6ecb2f148ad007b554.1563413318.git.jpoimboe@redhat.com
79 lines
1.3 KiB
C
79 lines
1.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/*
|
|
* Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
|
|
*/
|
|
|
|
#ifndef _ARCH_H
|
|
#define _ARCH_H
|
|
|
|
#include <stdbool.h>
|
|
#include <linux/list.h>
|
|
#include "elf.h"
|
|
#include "cfi.h"
|
|
|
|
enum insn_type {
|
|
INSN_JUMP_CONDITIONAL,
|
|
INSN_JUMP_UNCONDITIONAL,
|
|
INSN_JUMP_DYNAMIC,
|
|
INSN_JUMP_DYNAMIC_CONDITIONAL,
|
|
INSN_CALL,
|
|
INSN_CALL_DYNAMIC,
|
|
INSN_RETURN,
|
|
INSN_CONTEXT_SWITCH,
|
|
INSN_STACK,
|
|
INSN_BUG,
|
|
INSN_NOP,
|
|
INSN_STAC,
|
|
INSN_CLAC,
|
|
INSN_STD,
|
|
INSN_CLD,
|
|
INSN_OTHER,
|
|
};
|
|
|
|
enum op_dest_type {
|
|
OP_DEST_REG,
|
|
OP_DEST_REG_INDIRECT,
|
|
OP_DEST_MEM,
|
|
OP_DEST_PUSH,
|
|
OP_DEST_PUSHF,
|
|
OP_DEST_LEAVE,
|
|
};
|
|
|
|
struct op_dest {
|
|
enum op_dest_type type;
|
|
unsigned char reg;
|
|
int offset;
|
|
};
|
|
|
|
enum op_src_type {
|
|
OP_SRC_REG,
|
|
OP_SRC_REG_INDIRECT,
|
|
OP_SRC_CONST,
|
|
OP_SRC_POP,
|
|
OP_SRC_POPF,
|
|
OP_SRC_ADD,
|
|
OP_SRC_AND,
|
|
};
|
|
|
|
struct op_src {
|
|
enum op_src_type type;
|
|
unsigned char reg;
|
|
int offset;
|
|
};
|
|
|
|
struct stack_op {
|
|
struct op_dest dest;
|
|
struct op_src src;
|
|
};
|
|
|
|
void arch_initial_func_cfi_state(struct cfi_state *state);
|
|
|
|
int arch_decode_instruction(struct elf *elf, struct section *sec,
|
|
unsigned long offset, unsigned int maxlen,
|
|
unsigned int *len, enum insn_type *type,
|
|
unsigned long *immediate, struct stack_op *op);
|
|
|
|
bool arch_callee_saved_reg(unsigned char reg);
|
|
|
|
#endif /* _ARCH_H */
|