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1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _ASM_GENERIC_BUG_H 3#define _ASM_GENERIC_BUG_H 4 5#include <linux/compiler.h> 6 7#define CUT_HERE "------------[ cut here ]------------\n" 8 9#ifdef CONFIG_GENERIC_BUG 10#define BUGFLAG_WARNING (1 << 0) 11#define BUGFLAG_ONCE (1 << 1) 12#define BUGFLAG_DONE (1 << 2) 13#define BUGFLAG_TAINT(taint) ((taint) << 8) 14#define BUG_GET_TAINT(bug) ((bug)->flags >> 8) 15#endif 16 17#ifndef __ASSEMBLY__ 18#include <linux/kernel.h> 19 20#ifdef CONFIG_BUG 21 22#ifdef CONFIG_GENERIC_BUG 23struct bug_entry { 24#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS 25 unsigned long bug_addr; 26#else 27 signed int bug_addr_disp; 28#endif 29#ifdef CONFIG_DEBUG_BUGVERBOSE 30#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS 31 const char *file; 32#else 33 signed int file_disp; 34#endif 35 unsigned short line; 36#endif 37 unsigned short flags; 38}; 39#endif /* CONFIG_GENERIC_BUG */ 40 41/* 42 * Don't use BUG() or BUG_ON() unless there's really no way out; one 43 * example might be detecting data structure corruption in the middle 44 * of an operation that can't be backed out of. If the (sub)system 45 * can somehow continue operating, perhaps with reduced functionality, 46 * it's probably not BUG-worthy. 47 * 48 * If you're tempted to BUG(), think again: is completely giving up 49 * really the *only* solution? There are usually better options, where 50 * users don't need to reboot ASAP and can mostly shut down cleanly. 51 */ 52#ifndef HAVE_ARCH_BUG 53#define BUG() do { \ 54 printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \ 55 barrier_before_unreachable(); \ 56 panic("BUG!"); \ 57} while (0) 58#endif 59 60#ifndef HAVE_ARCH_BUG_ON 61#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) 62#endif 63 64#ifdef __WARN_FLAGS 65#define __WARN_TAINT(taint) __WARN_FLAGS(BUGFLAG_TAINT(taint)) 66#define __WARN_ONCE_TAINT(taint) __WARN_FLAGS(BUGFLAG_ONCE|BUGFLAG_TAINT(taint)) 67 68#define WARN_ON_ONCE(condition) ({ \ 69 int __ret_warn_on = !!(condition); \ 70 if (unlikely(__ret_warn_on)) \ 71 __WARN_ONCE_TAINT(TAINT_WARN); \ 72 unlikely(__ret_warn_on); \ 73}) 74#endif 75 76/* 77 * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report 78 * significant issues that need prompt attention if they should ever 79 * appear at runtime. Use the versions with printk format strings 80 * to provide better diagnostics. 81 */ 82#ifndef __WARN_TAINT 83extern __printf(3, 4) 84void warn_slowpath_fmt(const char *file, const int line, 85 const char *fmt, ...); 86extern __printf(4, 5) 87void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint, 88 const char *fmt, ...); 89extern void warn_slowpath_null(const char *file, const int line); 90#define WANT_WARN_ON_SLOWPATH 91#define __WARN() warn_slowpath_null(__FILE__, __LINE__) 92#define __WARN_printf(arg...) warn_slowpath_fmt(__FILE__, __LINE__, arg) 93#define __WARN_printf_taint(taint, arg...) \ 94 warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg) 95#else 96extern __printf(1, 2) void __warn_printk(const char *fmt, ...); 97#define __WARN() __WARN_TAINT(TAINT_WARN) 98#define __WARN_printf(arg...) do { __warn_printk(arg); __WARN(); } while (0) 99#define __WARN_printf_taint(taint, arg...) \ 100 do { __warn_printk(arg); __WARN_TAINT(taint); } while (0) 101#endif 102 103/* used internally by panic.c */ 104struct warn_args; 105struct pt_regs; 106 107void __warn(const char *file, int line, void *caller, unsigned taint, 108 struct pt_regs *regs, struct warn_args *args); 109 110#ifndef WARN_ON 111#define WARN_ON(condition) ({ \ 112 int __ret_warn_on = !!(condition); \ 113 if (unlikely(__ret_warn_on)) \ 114 __WARN(); \ 115 unlikely(__ret_warn_on); \ 116}) 117#endif 118 119#ifndef WARN 120#define WARN(condition, format...) ({ \ 121 int __ret_warn_on = !!(condition); \ 122 if (unlikely(__ret_warn_on)) \ 123 __WARN_printf(format); \ 124 unlikely(__ret_warn_on); \ 125}) 126#endif 127 128#define WARN_TAINT(condition, taint, format...) ({ \ 129 int __ret_warn_on = !!(condition); \ 130 if (unlikely(__ret_warn_on)) \ 131 __WARN_printf_taint(taint, format); \ 132 unlikely(__ret_warn_on); \ 133}) 134 135#ifndef WARN_ON_ONCE 136#define WARN_ON_ONCE(condition) ({ \ 137 static bool __section(.data.once) __warned; \ 138 int __ret_warn_once = !!(condition); \ 139 \ 140 if (unlikely(__ret_warn_once && !__warned)) { \ 141 __warned = true; \ 142 WARN_ON(1); \ 143 } \ 144 unlikely(__ret_warn_once); \ 145}) 146#endif 147 148#define WARN_ONCE(condition, format...) ({ \ 149 static bool __section(.data.once) __warned; \ 150 int __ret_warn_once = !!(condition); \ 151 \ 152 if (unlikely(__ret_warn_once && !__warned)) { \ 153 __warned = true; \ 154 WARN(1, format); \ 155 } \ 156 unlikely(__ret_warn_once); \ 157}) 158 159#define WARN_TAINT_ONCE(condition, taint, format...) ({ \ 160 static bool __section(.data.once) __warned; \ 161 int __ret_warn_once = !!(condition); \ 162 \ 163 if (unlikely(__ret_warn_once && !__warned)) { \ 164 __warned = true; \ 165 WARN_TAINT(1, taint, format); \ 166 } \ 167 unlikely(__ret_warn_once); \ 168}) 169 170#else /* !CONFIG_BUG */ 171#ifndef HAVE_ARCH_BUG 172#define BUG() do {} while (1) 173#endif 174 175#ifndef HAVE_ARCH_BUG_ON 176#define BUG_ON(condition) do { if (condition) BUG(); } while (0) 177#endif 178 179#ifndef HAVE_ARCH_WARN_ON 180#define WARN_ON(condition) ({ \ 181 int __ret_warn_on = !!(condition); \ 182 unlikely(__ret_warn_on); \ 183}) 184#endif 185 186#ifndef WARN 187#define WARN(condition, format...) ({ \ 188 int __ret_warn_on = !!(condition); \ 189 no_printk(format); \ 190 unlikely(__ret_warn_on); \ 191}) 192#endif 193 194#define WARN_ON_ONCE(condition) WARN_ON(condition) 195#define WARN_ONCE(condition, format...) WARN(condition, format) 196#define WARN_TAINT(condition, taint, format...) WARN(condition, format) 197#define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format) 198 199#endif 200 201/* 202 * WARN_ON_SMP() is for cases that the warning is either 203 * meaningless for !SMP or may even cause failures. 204 * This is usually used for cases that we have 205 * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked() 206 * returns 0 for uniprocessor settings. 207 * It can also be used with values that are only defined 208 * on SMP: 209 * 210 * struct foo { 211 * [...] 212 * #ifdef CONFIG_SMP 213 * int bar; 214 * #endif 215 * }; 216 * 217 * void func(struct foo *zoot) 218 * { 219 * WARN_ON_SMP(!zoot->bar); 220 * 221 * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(), 222 * and should be a nop and return false for uniprocessor. 223 * 224 * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set 225 * and x is true. 226 */ 227#ifdef CONFIG_SMP 228# define WARN_ON_SMP(x) WARN_ON(x) 229#else 230/* 231 * Use of ({0;}) because WARN_ON_SMP(x) may be used either as 232 * a stand alone line statement or as a condition in an if () 233 * statement. 234 * A simple "0" would cause gcc to give a "statement has no effect" 235 * warning. 236 */ 237# define WARN_ON_SMP(x) ({0;}) 238#endif 239 240#endif /* __ASSEMBLY__ */ 241 242#endif