projects/linux·blob uaccess-cleanups · refs

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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#include <linux/instrumentation.h>
7#include <linux/once_lite.h>
8
9#define CUT_HERE "------------[ cut here ]------------\n"
10
11#ifdef CONFIG_GENERIC_BUG
12#define BUGFLAG_WARNING (1 << 0)
13#define BUGFLAG_ONCE (1 << 1)
14#define BUGFLAG_DONE (1 << 2)
15#define BUGFLAG_NO_CUT_HERE (1 << 3) /* CUT_HERE already sent */
16#define BUGFLAG_ARGS (1 << 4)
17#define BUGFLAG_TAINT(taint) ((taint) << 8)
18#define BUG_GET_TAINT(bug) ((bug)->flags >> 8)
19#endif
20
21#ifndef WARN_CONDITION_STR
22#ifdef CONFIG_DEBUG_BUGVERBOSE_DETAILED
23# define WARN_CONDITION_STR(cond_str) "[" cond_str "] "
24#else
25# define WARN_CONDITION_STR(cond_str)
26#endif
27#endif /* WARN_CONDITION_STR */
28
29#ifndef __ASSEMBLY__
30#include <linux/panic.h>
31#include <linux/printk.h>
32
33struct warn_args;
34struct pt_regs;
35
36void __warn(const char *file, int line, void *caller, unsigned taint,
37 struct pt_regs *regs, struct warn_args *args);
38
39#ifdef CONFIG_BUG
40
41#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
42#define BUG_REL(type, name) type name
43#else
44#define BUG_REL(type, name) signed int name##_disp
45#endif
46
47#ifdef CONFIG_GENERIC_BUG
48struct bug_entry {
49 BUG_REL(unsigned long, bug_addr);
50#ifdef HAVE_ARCH_BUG_FORMAT
51 BUG_REL(const char *, format);
52#endif
53#ifdef CONFIG_DEBUG_BUGVERBOSE
54 BUG_REL(const char *, file);
55 unsigned short line;
56#endif
57 unsigned short flags;
58};
59#endif /* CONFIG_GENERIC_BUG */
60
61/*
62 * Don't use BUG() or BUG_ON() unless there's really no way out; one
63 * example might be detecting data structure corruption in the middle
64 * of an operation that can't be backed out of. If the (sub)system
65 * can somehow continue operating, perhaps with reduced functionality,
66 * it's probably not BUG-worthy.
67 *
68 * If you're tempted to BUG(), think again: is completely giving up
69 * really the *only* solution? There are usually better options, where
70 * users don't need to reboot ASAP and can mostly shut down cleanly.
71 */
72#ifndef HAVE_ARCH_BUG
73#define BUG() do { \
74 printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
75 barrier_before_unreachable(); \
76 panic("BUG!"); \
77} while (0)
78#endif
79
80#ifndef HAVE_ARCH_BUG_ON
81#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
82#endif
83
84/*
85 * WARN(), WARN_ON(), WARN_ON_ONCE(), and so on can be used to report
86 * significant kernel issues that need prompt attention if they should ever
87 * appear at runtime.
88 *
89 * Do not use these macros when checking for invalid external inputs
90 * (e.g. invalid system call arguments, or invalid data coming from
91 * network/devices), and on transient conditions like ENOMEM or EAGAIN.
92 * These macros should be used for recoverable kernel issues only.
93 * For invalid external inputs, transient conditions, etc use
94 * pr_err[_once/_ratelimited]() followed by dump_stack(), if necessary.
95 * Do not include "BUG"/"WARNING" in format strings manually to make these
96 * conditions distinguishable from kernel issues.
97 *
98 * Use the versions with printk format strings to provide better diagnostics.
99 */
100extern __printf(4, 5)
101void warn_slowpath_fmt(const char *file, const int line, unsigned taint,
102 const char *fmt, ...);
103extern __printf(1, 2) void __warn_printk(const char *fmt, ...);
104
105#ifdef __WARN_FLAGS
106#define __WARN() __WARN_FLAGS("", BUGFLAG_TAINT(TAINT_WARN))
107
108#ifndef WARN_ON
109#define WARN_ON(condition) ({ \
110 int __ret_warn_on = !!(condition); \
111 if (unlikely(__ret_warn_on)) \
112 __WARN_FLAGS(#condition, \
113 BUGFLAG_TAINT(TAINT_WARN)); \
114 unlikely(__ret_warn_on); \
115})
116#endif
117
118#ifndef WARN_ON_ONCE
119#define WARN_ON_ONCE(condition) ({ \
120 int __ret_warn_on = !!(condition); \
121 if (unlikely(__ret_warn_on)) \
122 __WARN_FLAGS(#condition, \
123 BUGFLAG_ONCE | \
124 BUGFLAG_TAINT(TAINT_WARN)); \
125 unlikely(__ret_warn_on); \
126})
127#endif
128#endif /* __WARN_FLAGS */
129
130#if defined(__WARN_FLAGS) && !defined(__WARN_printf)
131#define __WARN_printf(taint, arg...) do { \
132 instrumentation_begin(); \
133 __warn_printk(arg); \
134 __WARN_FLAGS("", BUGFLAG_NO_CUT_HERE | BUGFLAG_TAINT(taint));\
135 instrumentation_end(); \
136 } while (0)
137#endif
138
139#ifndef __WARN_printf
140#define __WARN_printf(taint, arg...) do { \
141 instrumentation_begin(); \
142 warn_slowpath_fmt(__FILE__, __LINE__, taint, arg); \
143 instrumentation_end(); \
144 } while (0)
145#endif
146
147#ifndef __WARN
148#define __WARN() __WARN_printf(TAINT_WARN, NULL)
149#endif
150
151/* used internally by panic.c */
152
153#ifndef WARN_ON
154#define WARN_ON(condition) ({ \
155 int __ret_warn_on = !!(condition); \
156 if (unlikely(__ret_warn_on)) \
157 __WARN(); \
158 unlikely(__ret_warn_on); \
159})
160#endif
161
162#ifndef WARN
163#define WARN(condition, format...) ({ \
164 int __ret_warn_on = !!(condition); \
165 if (unlikely(__ret_warn_on)) \
166 __WARN_printf(TAINT_WARN, format); \
167 unlikely(__ret_warn_on); \
168})
169#endif
170
171#define WARN_TAINT(condition, taint, format...) ({ \
172 int __ret_warn_on = !!(condition); \
173 if (unlikely(__ret_warn_on)) \
174 __WARN_printf(taint, format); \
175 unlikely(__ret_warn_on); \
176})
177
178#ifndef WARN_ON_ONCE
179#define WARN_ON_ONCE(condition) \
180 DO_ONCE_LITE_IF(condition, WARN_ON, 1)
181#endif
182
183#ifndef WARN_ONCE
184#define WARN_ONCE(condition, format...) \
185 DO_ONCE_LITE_IF(condition, WARN, 1, format)
186#endif
187
188#define WARN_TAINT_ONCE(condition, taint, format...) \
189 DO_ONCE_LITE_IF(condition, WARN_TAINT, 1, taint, format)
190
191#else /* !CONFIG_BUG */
192#ifndef HAVE_ARCH_BUG
193#define BUG() do { \
194 do {} while (1); \
195 unreachable(); \
196} while (0)
197#endif
198
199#ifndef HAVE_ARCH_BUG_ON
200#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
201#endif
202
203#ifndef HAVE_ARCH_WARN_ON
204#define WARN_ON(condition) ({ \
205 int __ret_warn_on = !!(condition); \
206 unlikely(__ret_warn_on); \
207})
208#endif
209
210#ifndef WARN
211#define WARN(condition, format...) ({ \
212 int __ret_warn_on = !!(condition); \
213 no_printk(format); \
214 unlikely(__ret_warn_on); \
215})
216#endif
217
218#define WARN_ON_ONCE(condition) WARN_ON(condition)
219#define WARN_ONCE(condition, format...) WARN(condition, format)
220#define WARN_TAINT(condition, taint, format...) WARN(condition, format)
221#define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format)
222
223#endif
224
225/*
226 * WARN_ON_SMP() is for cases that the warning is either
227 * meaningless for !SMP or may even cause failures.
228 * It can also be used with values that are only defined
229 * on SMP:
230 *
231 * struct foo {
232 * [...]
233 * #ifdef CONFIG_SMP
234 * int bar;
235 * #endif
236 * };
237 *
238 * void func(struct foo *zoot)
239 * {
240 * WARN_ON_SMP(!zoot->bar);
241 *
242 * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
243 * and should be a nop and return false for uniprocessor.
244 *
245 * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
246 * and x is true.
247 */
248#ifdef CONFIG_SMP
249# define WARN_ON_SMP(x) WARN_ON(x)
250#else
251/*
252 * Use of ({0;}) because WARN_ON_SMP(x) may be used either as
253 * a stand alone line statement or as a condition in an if ()
254 * statement.
255 * A simple "0" would cause gcc to give a "statement has no effect"
256 * warning.
257 */
258# define WARN_ON_SMP(x) ({0;})
259#endif
260
261#endif /* __ASSEMBLY__ */
262
263#endif