include/asm/bug.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef _ASMARM_BUG_H
0003 #define _ASMARM_BUG_H
0004
0005 #include <linux/linkage.h>
0006 #include <linux/types.h>
0007 #include <asm/opcodes.h>
0008
0009 /*
0010  * Use a suitable undefined instruction to use for ARM/Thumb2 bug handling.
0011  * We need to be careful not to conflict with those used by other modules and
0012  * the register_undef_hook() system.
0013  */
0014 #ifdef CONFIG_THUMB2_KERNEL
0015 #define BUG_INSTR_VALUE 0xde02
0016 #define BUG_INSTR(__value) __inst_thumb16(__value)
0017 #else
0018 #define BUG_INSTR_VALUE 0xe7f001f2
0019 #define BUG_INSTR(__value) __inst_arm(__value)
0020 #endif
0021
0022
0023 #define BUG() _BUG(__FILE__, __LINE__, BUG_INSTR_VALUE)
0024 #define _BUG(file, line, value) __BUG(file, line, value)
0025
0026 #ifdef CONFIG_DEBUG_BUGVERBOSE
0027
0028 /*
0029  * The extra indirection is to ensure that the __FILE__ string comes through
0030  * OK. Many version of gcc do not support the asm %c parameter which would be
0031  * preferable to this unpleasantness. We use mergeable string sections to
0032  * avoid multiple copies of the string appearing in the kernel image.
0033  */
0034
0035 #define __BUG(__file, __line, __value)              \
0036 do {                                \
0037     asm volatile("1:\t" BUG_INSTR(__value) "\n"  \
0038         ".pushsection .rodata.str, \"aMS\", %progbits, 1\n" \
0039         "2:\t.asciz " #__file "\n"          \
0040         ".popsection\n"                 \
0041         ".pushsection __bug_table,\"aw\"\n"     \
0042         ".align 2\n"                    \
0043         "3:\t.word 1b, 2b\n"                \
0044         "\t.hword " #__line ", 0\n"         \
0045         ".popsection");                 \
0046     unreachable();                      \
0047 } while (0)
0048
0049 #else
0050
0051 #define __BUG(__file, __line, __value)              \
0052 do {                                \
0053     asm volatile(BUG_INSTR(__value) "\n");          \
0054     unreachable();                      \
0055 } while (0)
0056 #endif  /* CONFIG_DEBUG_BUGVERBOSE */
0057
0058 #define HAVE_ARCH_BUG
0059
0060 #include <asm-generic/bug.h>
0061
0062 struct pt_regs;
0063 void die(const char *msg, struct pt_regs *regs, int err);
0064
0065 void arm_notify_die(const char *str, struct pt_regs *regs,
0066         int signo, int si_code, void __user *addr,
0067         unsigned long err, unsigned long trap);
0068
0069 #ifdef CONFIG_ARM_LPAE
0070 #define FAULT_CODE_ALIGNMENT    33
0071 #define FAULT_CODE_DEBUG    34
0072 #else
0073 #define FAULT_CODE_ALIGNMENT    1
0074 #define FAULT_CODE_DEBUG    2
0075 #endif
0076
0077 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
0078                        struct pt_regs *),
0079              int sig, int code, const char *name);
0080
0081 void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
0082                        struct pt_regs *),
0083              int sig, int code, const char *name);
0084
0085 extern asmlinkage void c_backtrace(unsigned long fp, int pmode,
0086                    const char *loglvl);
0087
0088 struct mm_struct;
0089 void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr);
0090 extern void __show_regs(struct pt_regs *);
0091 extern void __show_regs_alloc_free(struct pt_regs *regs);
0092
0093 #endif