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 23 struct 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 panic("BUG!"); \ 56 } while (0) 57 #endif 58 59 #ifndef HAVE_ARCH_BUG_ON 60 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) 61 #endif 62 63 #ifdef __WARN_FLAGS 64 #define __WARN_TAINT(taint) __WARN_FLAGS(BUGFLAG_TAINT(taint)) 65 #define __WARN_ONCE_TAINT(taint) __WARN_FLAGS(BUGFLAG_ONCE|BUGFLAG_TAINT(taint)) 66 67 #define WARN_ON_ONCE(condition) ({ \ 68 int __ret_warn_on = !!(condition); \ 69 if (unlikely(__ret_warn_on)) \ 70 __WARN_ONCE_TAINT(TAINT_WARN); \ 71 unlikely(__ret_warn_on); \ 72 }) 73 #endif 74 75 /* 76 * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report 77 * significant issues that need prompt attention if they should ever 78 * appear at runtime. Use the versions with printk format strings 79 * to provide better diagnostics. 80 */ 81 #ifndef __WARN_TAINT 82 extern __printf(3, 4) 83 void warn_slowpath_fmt(const char *file, const int line, 84 const char *fmt, ...); 85 extern __printf(4, 5) 86 void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint, 87 const char *fmt, ...); 88 extern void warn_slowpath_null(const char *file, const int line); 89 #define WANT_WARN_ON_SLOWPATH 90 #define __WARN() warn_slowpath_null(__FILE__, __LINE__) 91 #define __WARN_printf(arg...) warn_slowpath_fmt(__FILE__, __LINE__, arg) 92 #define __WARN_printf_taint(taint, arg...) \ 93 warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg) 94 #else 95 #define __WARN() __WARN_TAINT(TAINT_WARN) 96 #define __WARN_printf(arg...) do { printk(arg); __WARN(); } while (0) 97 #define __WARN_printf_taint(taint, arg...) \ 98 do { printk(arg); __WARN_TAINT(taint); } while (0) 99 #endif 100 101 /* used internally by panic.c */ 102 struct warn_args; 103 struct pt_regs; 104 105 void __warn(const char *file, int line, void *caller, unsigned taint, 106 struct pt_regs *regs, struct warn_args *args); 107 108 #ifndef WARN_ON 109 #define WARN_ON(condition) ({ \ 110 int __ret_warn_on = !!(condition); \ 111 if (unlikely(__ret_warn_on)) \ 112 __WARN(); \ 113 unlikely(__ret_warn_on); \ 114 }) 115 #endif 116 117 #ifndef WARN 118 #define WARN(condition, format...) ({ \ 119 int __ret_warn_on = !!(condition); \ 120 if (unlikely(__ret_warn_on)) \ 121 __WARN_printf(format); \ 122 unlikely(__ret_warn_on); \ 123 }) 124 #endif 125 126 #define WARN_TAINT(condition, taint, format...) ({ \ 127 int __ret_warn_on = !!(condition); \ 128 if (unlikely(__ret_warn_on)) \ 129 __WARN_printf_taint(taint, format); \ 130 unlikely(__ret_warn_on); \ 131 }) 132 133 #ifndef WARN_ON_ONCE 134 #define WARN_ON_ONCE(condition) ({ \ 135 static bool __section(.data.once) __warned; \ 136 int __ret_warn_once = !!(condition); \ 137 \ 138 if (unlikely(__ret_warn_once && !__warned)) { \ 139 __warned = true; \ 140 WARN_ON(1); \ 141 } \ 142 unlikely(__ret_warn_once); \ 143 }) 144 #endif 145 146 #define WARN_ONCE(condition, format...) ({ \ 147 static bool __section(.data.once) __warned; \ 148 int __ret_warn_once = !!(condition); \ 149 \ 150 if (unlikely(__ret_warn_once && !__warned)) { \ 151 __warned = true; \ 152 WARN(1, format); \ 153 } \ 154 unlikely(__ret_warn_once); \ 155 }) 156 157 #define WARN_TAINT_ONCE(condition, taint, format...) ({ \ 158 static bool __section(.data.once) __warned; \ 159 int __ret_warn_once = !!(condition); \ 160 \ 161 if (unlikely(__ret_warn_once && !__warned)) { \ 162 __warned = true; \ 163 WARN_TAINT(1, taint, format); \ 164 } \ 165 unlikely(__ret_warn_once); \ 166 }) 167 168 #else /* !CONFIG_BUG */ 169 #ifndef HAVE_ARCH_BUG 170 #define BUG() do {} while (1) 171 #endif 172 173 #ifndef HAVE_ARCH_BUG_ON 174 #define BUG_ON(condition) do { if (condition) BUG(); } while (0) 175 #endif 176 177 #ifndef HAVE_ARCH_WARN_ON 178 #define WARN_ON(condition) ({ \ 179 int __ret_warn_on = !!(condition); \ 180 unlikely(__ret_warn_on); \ 181 }) 182 #endif 183 184 #ifndef WARN 185 #define WARN(condition, format...) ({ \ 186 int __ret_warn_on = !!(condition); \ 187 no_printk(format); \ 188 unlikely(__ret_warn_on); \ 189 }) 190 #endif 191 192 #define WARN_ON_ONCE(condition) WARN_ON(condition) 193 #define WARN_ONCE(condition, format...) WARN(condition, format) 194 #define WARN_TAINT(condition, taint, format...) WARN(condition, format) 195 #define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format) 196 197 #endif 198 199 /* 200 * WARN_ON_SMP() is for cases that the warning is either 201 * meaningless for !SMP or may even cause failures. 202 * This is usually used for cases that we have 203 * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked() 204 * returns 0 for uniprocessor settings. 205 * It can also be used with values that are only defined 206 * on SMP: 207 * 208 * struct foo { 209 * [...] 210 * #ifdef CONFIG_SMP 211 * int bar; 212 * #endif 213 * }; 214 * 215 * void func(struct foo *zoot) 216 * { 217 * WARN_ON_SMP(!zoot->bar); 218 * 219 * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(), 220 * and should be a nop and return false for uniprocessor. 221 * 222 * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set 223 * and x is true. 224 */ 225 #ifdef CONFIG_SMP 226 # define WARN_ON_SMP(x) WARN_ON(x) 227 #else 228 /* 229 * Use of ({0;}) because WARN_ON_SMP(x) may be used either as 230 * a stand alone line statement or as a condition in an if () 231 * statement. 232 * A simple "0" would cause gcc to give a "statement has no effect" 233 * warning. 234 */ 235 # define WARN_ON_SMP(x) ({0;}) 236 #endif 237 238 #endif /* __ASSEMBLY__ */ 239 240 #endif 241