1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASMARM_BUG_H
3#define _ASMARM_BUG_H
4
5#include <linux/linkage.h>
6#include <linux/types.h>
7#include <asm/opcodes.h>
8
9/*
10 * Use a suitable undefined instruction to use for ARM/Thumb2 bug handling.
11 * We need to be careful not to conflict with those used by other modules and
12 * the register_undef_hook() system.
13 */
14#ifdef CONFIG_THUMB2_KERNEL
15#define BUG_INSTR_VALUE 0xde02
16#define BUG_INSTR(__value) __inst_thumb16(__value)
17#else
18#define BUG_INSTR_VALUE 0xe7f001f2
19#define BUG_INSTR(__value) __inst_arm(__value)
20#endif
21
22
23#define BUG() _BUG(__FILE__, __LINE__, BUG_INSTR_VALUE)
24#define _BUG(file, line, value) __BUG(file, line, value)
25
26#ifdef CONFIG_DEBUG_BUGVERBOSE
27
28/*
29 * The extra indirection is to ensure that the __FILE__ string comes through
30 * OK. Many version of gcc do not support the asm %c parameter which would be
31 * preferable to this unpleasantness. We use mergeable string sections to
32 * avoid multiple copies of the string appearing in the kernel image.
33 */
34
35#define __BUG(__file, __line, __value)				\
36do {								\
37	asm volatile("1:\t" BUG_INSTR(__value) "\n"  \
38		".pushsection .rodata.str, \"aMS\", %progbits, 1\n" \
39		"2:\t.asciz " #__file "\n" 			\
40		".popsection\n" 				\
41		".pushsection __bug_table,\"aw\"\n"		\
42		".align 2\n"					\
43		"3:\t.word 1b, 2b\n"				\
44		"\t.hword " #__line ", 0\n"			\
45		".popsection");					\
46	unreachable();						\
47} while (0)
48
49#else
50
51#define __BUG(__file, __line, __value)				\
52do {								\
53	asm volatile(BUG_INSTR(__value) "\n");			\
54	unreachable();						\
55} while (0)
56#endif  /* CONFIG_DEBUG_BUGVERBOSE */
57
58#define HAVE_ARCH_BUG
59
60#include <asm-generic/bug.h>
61
62struct pt_regs;
63void die(const char *msg, struct pt_regs *regs, int err);
64
65void arm_notify_die(const char *str, struct pt_regs *regs,
66		int signo, int si_code, void __user *addr,
67		unsigned long err, unsigned long trap);
68
69#ifdef CONFIG_ARM_LPAE
70#define FAULT_CODE_ALIGNMENT	33
71#define FAULT_CODE_DEBUG	34
72#else
73#define FAULT_CODE_ALIGNMENT	1
74#define FAULT_CODE_DEBUG	2
75#endif
76
77void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
78				       struct pt_regs *),
79		     int sig, int code, const char *name);
80
81void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
82				       struct pt_regs *),
83		     int sig, int code, const char *name);
84
85extern asmlinkage void c_backtrace(unsigned long fp, int pmode,
86				   const char *loglvl);
87
88struct mm_struct;
89void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr);
90extern void __show_regs(struct pt_regs *);
91extern void __show_regs_alloc_free(struct pt_regs *regs);
92
93#endif
94