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