xref: /linux-6.15/include/asm-generic/bug.h (revision 74ca4313)
1 #ifndef _ASM_GENERIC_BUG_H
2 #define _ASM_GENERIC_BUG_H
3 
4 #include <linux/compiler.h>
5 #include <linux/kernel.h>
6 
7 #ifdef CONFIG_BUG
8 
9 #ifdef CONFIG_GENERIC_BUG
10 #ifndef __ASSEMBLY__
11 struct bug_entry {
12 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
13 	unsigned long	bug_addr;
14 #else
15 	signed int	bug_addr_disp;
16 #endif
17 #ifdef CONFIG_DEBUG_BUGVERBOSE
18 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
19 	const char	*file;
20 #else
21 	signed int	file_disp;
22 #endif
23 	unsigned short	line;
24 #endif
25 	unsigned short	flags;
26 };
27 #endif		/* __ASSEMBLY__ */
28 
29 #define BUGFLAG_WARNING		(1 << 0)
30 #define BUGFLAG_TAINT(taint)	(BUGFLAG_WARNING | ((taint) << 8))
31 #define BUG_GET_TAINT(bug)	((bug)->flags >> 8)
32 
33 #endif	/* CONFIG_GENERIC_BUG */
34 
35 /*
36  * Don't use BUG() or BUG_ON() unless there's really no way out; one
37  * example might be detecting data structure corruption in the middle
38  * of an operation that can't be backed out of.  If the (sub)system
39  * can somehow continue operating, perhaps with reduced functionality,
40  * it's probably not BUG-worthy.
41  *
42  * If you're tempted to BUG(), think again:  is completely giving up
43  * really the *only* solution?  There are usually better options, where
44  * users don't need to reboot ASAP and can mostly shut down cleanly.
45  */
46 #ifndef HAVE_ARCH_BUG
47 #define BUG() do { \
48 	printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
49 	panic("BUG!"); \
50 } while (0)
51 #endif
52 
53 #ifndef HAVE_ARCH_BUG_ON
54 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
55 #endif
56 
57 /*
58  * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
59  * significant issues that need prompt attention if they should ever
60  * appear at runtime.  Use the versions with printk format strings
61  * to provide better diagnostics.
62  */
63 #ifndef __WARN_TAINT
64 #ifndef __ASSEMBLY__
65 extern __printf(3, 4)
66 void warn_slowpath_fmt(const char *file, const int line,
67 		       const char *fmt, ...);
68 extern __printf(4, 5)
69 void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint,
70 			     const char *fmt, ...);
71 extern void warn_slowpath_null(const char *file, const int line);
72 #define WANT_WARN_ON_SLOWPATH
73 #endif
74 #define __WARN()		warn_slowpath_null(__FILE__, __LINE__)
75 #define __WARN_printf(arg...)	warn_slowpath_fmt(__FILE__, __LINE__, arg)
76 #define __WARN_printf_taint(taint, arg...)				\
77 	warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg)
78 #else
79 #define __WARN()		__WARN_TAINT(TAINT_WARN)
80 #define __WARN_printf(arg...)	do { printk(arg); __WARN(); } while (0)
81 #define __WARN_printf_taint(taint, arg...)				\
82 	do { printk(arg); __WARN_TAINT(taint); } while (0)
83 #endif
84 
85 #ifndef WARN_ON
86 #define WARN_ON(condition) ({						\
87 	int __ret_warn_on = !!(condition);				\
88 	if (unlikely(__ret_warn_on))					\
89 		__WARN();						\
90 	unlikely(__ret_warn_on);					\
91 })
92 #endif
93 
94 #ifndef WARN
95 #define WARN(condition, format...) ({						\
96 	int __ret_warn_on = !!(condition);				\
97 	if (unlikely(__ret_warn_on))					\
98 		__WARN_printf(format);					\
99 	unlikely(__ret_warn_on);					\
100 })
101 #endif
102 
103 #define WARN_TAINT(condition, taint, format...) ({			\
104 	int __ret_warn_on = !!(condition);				\
105 	if (unlikely(__ret_warn_on))					\
106 		__WARN_printf_taint(taint, format);			\
107 	unlikely(__ret_warn_on);					\
108 })
109 
110 #else /* !CONFIG_BUG */
111 #ifndef HAVE_ARCH_BUG
112 #define BUG() do {} while(0)
113 #endif
114 
115 #ifndef HAVE_ARCH_BUG_ON
116 #define BUG_ON(condition) do { if (condition) ; } while(0)
117 #endif
118 
119 #ifndef HAVE_ARCH_WARN_ON
120 #define WARN_ON(condition) ({						\
121 	int __ret_warn_on = !!(condition);				\
122 	unlikely(__ret_warn_on);					\
123 })
124 #endif
125 
126 #ifndef WARN
127 #define WARN(condition, format...) ({					\
128 	int __ret_warn_on = !!(condition);				\
129 	unlikely(__ret_warn_on);					\
130 })
131 #endif
132 
133 #define WARN_TAINT(condition, taint, format...) WARN_ON(condition)
134 
135 #endif
136 
137 #define WARN_ON_ONCE(condition)	({				\
138 	static bool __section(.data.unlikely) __warned;		\
139 	int __ret_warn_once = !!(condition);			\
140 								\
141 	if (unlikely(__ret_warn_once))				\
142 		if (WARN_ON(!__warned)) 			\
143 			__warned = true;			\
144 	unlikely(__ret_warn_once);				\
145 })
146 
147 #define WARN_ONCE(condition, format...)	({			\
148 	static bool __section(.data.unlikely) __warned;		\
149 	int __ret_warn_once = !!(condition);			\
150 								\
151 	if (unlikely(__ret_warn_once))				\
152 		if (WARN(!__warned, format)) 			\
153 			__warned = true;			\
154 	unlikely(__ret_warn_once);				\
155 })
156 
157 #define WARN_TAINT_ONCE(condition, taint, format...)	({	\
158 	static bool __section(.data.unlikely) __warned;		\
159 	int __ret_warn_once = !!(condition);			\
160 								\
161 	if (unlikely(__ret_warn_once))				\
162 		if (WARN_TAINT(!__warned, taint, format))	\
163 			__warned = true;			\
164 	unlikely(__ret_warn_once);				\
165 })
166 
167 /*
168  * WARN_ON_SMP() is for cases that the warning is either
169  * meaningless for !SMP or may even cause failures.
170  * This is usually used for cases that we have
171  * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked()
172  * returns 0 for uniprocessor settings.
173  * It can also be used with values that are only defined
174  * on SMP:
175  *
176  * struct foo {
177  *  [...]
178  * #ifdef CONFIG_SMP
179  *	int bar;
180  * #endif
181  * };
182  *
183  * void func(struct foo *zoot)
184  * {
185  *	WARN_ON_SMP(!zoot->bar);
186  *
187  * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
188  * and should be a nop and return false for uniprocessor.
189  *
190  * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
191  * and x is true.
192  */
193 #ifdef CONFIG_SMP
194 # define WARN_ON_SMP(x)			WARN_ON(x)
195 #else
196 /*
197  * Use of ({0;}) because WARN_ON_SMP(x) may be used either as
198  * a stand alone line statement or as a condition in an if ()
199  * statement.
200  * A simple "0" would cause gcc to give a "statement has no effect"
201  * warning.
202  */
203 # define WARN_ON_SMP(x)			({0;})
204 #endif
205 
206 #endif
207