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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_GENERIC_BUG_H
#define _ASM_GENERIC_BUG_H
#include <linux/compiler.h>
#include <linux/instrumentation.h>
#define CUT_HERE "------------[ cut here ]------------\n"
#ifdef CONFIG_GENERIC_BUG
#define BUGFLAG_WARNING (1 << 0)
#define BUGFLAG_ONCE (1 << 1)
#define BUGFLAG_DONE (1 << 2)
#define BUGFLAG_NO_CUT_HERE (1 << 3) /* CUT_HERE already sent */
#define BUGFLAG_TAINT(taint) ((taint) << 8)
#define BUG_GET_TAINT(bug) ((bug)->flags >> 8)
#endif
#ifndef __ASSEMBLY__
#include <linux/kernel.h>
#ifdef CONFIG_BUG
#ifdef CONFIG_GENERIC_BUG
struct bug_entry {
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
unsigned long bug_addr;
#else
signed int bug_addr_disp;
#endif
#ifdef CONFIG_DEBUG_BUGVERBOSE
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
const char *file;
#else
signed int file_disp;
#endif
unsigned short line;
#endif
unsigned short flags;
};
#endif /* CONFIG_GENERIC_BUG */
/*
* Don't use BUG() or BUG_ON() unless there's really no way out; one
* example might be detecting data structure corruption in the middle
* of an operation that can't be backed out of. If the (sub)system
* can somehow continue operating, perhaps with reduced functionality,
* it's probably not BUG-worthy.
*
* If you're tempted to BUG(), think again: is completely giving up
* really the *only* solution? There are usually better options, where
* users don't need to reboot ASAP and can mostly shut down cleanly.
*/
#ifndef HAVE_ARCH_BUG
#define BUG() do { \
printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
barrier_before_unreachable(); \
panic("BUG!"); \
} while (0)
#endif
#ifndef HAVE_ARCH_BUG_ON
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
#endif
/*
* WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
* significant kernel issues that need prompt attention if they should ever
* appear at runtime.
*
* Do not use these macros when checking for invalid external inputs
* (e.g. invalid system call arguments, or invalid data coming from
* network/devices), and on transient conditions like ENOMEM or EAGAIN.
* These macros should be used for recoverable kernel issues only.
* For invalid external inputs, transient conditions, etc use
* pr_err[_once/_ratelimited]() followed by dump_stack(), if necessary.
* Do not include "BUG"/"WARNING" in format strings manually to make these
* conditions distinguishable from kernel issues.
*
* Use the versions with printk format strings to provide better diagnostics.
*/
#ifndef __WARN_FLAGS
extern __printf(4, 5)
void warn_slowpath_fmt(const char *file, const int line, unsigned taint,
const char *fmt, ...);
#define __WARN() __WARN_printf(TAINT_WARN, NULL)
#define __WARN_printf(taint, arg...) do { \
instrumentation_begin(); \
warn_slowpath_fmt(__FILE__, __LINE__, taint, arg); \
instrumentation_end(); \
} while (0)
#else
extern __printf(1, 2) void __warn_printk(const char *fmt, ...);
#define __WARN() __WARN_FLAGS(BUGFLAG_TAINT(TAINT_WARN))
#define __WARN_printf(taint, arg...) do { \
instrumentation_begin(); \
__warn_printk(arg); \
__WARN_FLAGS(BUGFLAG_NO_CUT_HERE | BUGFLAG_TAINT(taint));\
instrumentation_end(); \
} while (0)
#define WARN_ON_ONCE(condition) ({ \
int __ret_warn_on = !!(condition); \
if (unlikely(__ret_warn_on)) \
__WARN_FLAGS(BUGFLAG_ONCE | \
BUGFLAG_TAINT(TAINT_WARN)); \
unlikely(__ret_warn_on); \
})
#endif
/* used internally by panic.c */
struct warn_args;
struct pt_regs;
void __warn(const char *file, int line, void *caller, unsigned taint,
struct pt_regs *regs, struct warn_args *args);
#ifndef WARN_ON
#define WARN_ON(condition) ({ \
int __ret_warn_on = !!(condition); \
if (unlikely(__ret_warn_on)) \
__WARN(); \
unlikely(__ret_warn_on); \
})
#endif
#ifndef WARN
#define WARN(condition, format...) ({ \
int __ret_warn_on = !!(condition); \
if (unlikely(__ret_warn_on)) \
__WARN_printf(TAINT_WARN, format); \
unlikely(__ret_warn_on); \
})
#endif
#define WARN_TAINT(condition, taint, format...) ({ \
int __ret_warn_on = !!(condition); \
if (unlikely(__ret_warn_on)) \
__WARN_printf(taint, format); \
unlikely(__ret_warn_on); \
})
#ifndef WARN_ON_ONCE
#define WARN_ON_ONCE(condition) ({ \
static bool __section(".data.once") __warned; \
int __ret_warn_once = !!(condition); \
\
if (unlikely(__ret_warn_once && !__warned)) { \
__warned = true; \
WARN_ON(1); \
} \
unlikely(__ret_warn_once); \
})
#endif
#define WARN_ONCE(condition, format...) ({ \
static bool __section(".data.once") __warned; \
int __ret_warn_once = !!(condition); \
\
if (unlikely(__ret_warn_once && !__warned)) { \
__warned = true; \
WARN(1, format); \
} \
unlikely(__ret_warn_once); \
})
#define WARN_TAINT_ONCE(condition, taint, format...) ({ \
static bool __section(".data.once") __warned; \
int __ret_warn_once = !!(condition); \
\
if (unlikely(__ret_warn_once && !__warned)) { \
__warned = true; \
WARN_TAINT(1, taint, format); \
} \
unlikely(__ret_warn_once); \
})
#else /* !CONFIG_BUG */
#ifndef HAVE_ARCH_BUG
#define BUG() do {} while (1)
#endif
#ifndef HAVE_ARCH_BUG_ON
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
#endif
#ifndef HAVE_ARCH_WARN_ON
#define WARN_ON(condition) ({ \
int __ret_warn_on = !!(condition); \
unlikely(__ret_warn_on); \
})
#endif
#ifndef WARN
#define WARN(condition, format...) ({ \
int __ret_warn_on = !!(condition); \
no_printk(format); \
unlikely(__ret_warn_on); \
})
#endif
#define WARN_ON_ONCE(condition) WARN_ON(condition)
#define WARN_ONCE(condition, format...) WARN(condition, format)
#define WARN_TAINT(condition, taint, format...) WARN(condition, format)
#define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format)
#endif
/*
* WARN_ON_SMP() is for cases that the warning is either
* meaningless for !SMP or may even cause failures.
* It can also be used with values that are only defined
* on SMP:
*
* struct foo {
* [...]
* #ifdef CONFIG_SMP
* int bar;
* #endif
* };
*
* void func(struct foo *zoot)
* {
* WARN_ON_SMP(!zoot->bar);
*
* For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
* and should be a nop and return false for uniprocessor.
*
* if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
* and x is true.
*/
#ifdef CONFIG_SMP
# define WARN_ON_SMP(x) WARN_ON(x)
#else
/*
* Use of ({0;}) because WARN_ON_SMP(x) may be used either as
* a stand alone line statement or as a condition in an if ()
* statement.
* A simple "0" would cause gcc to give a "statement has no effect"
* warning.
*/
# define WARN_ON_SMP(x) ({0;})
#endif
/*
* WARN_ON_FUNCTION_MISMATCH() warns if a value doesn't match a
* function address, and can be useful for catching issues with
* callback functions, for example.
*
* With CONFIG_CFI_CLANG, the warning is disabled because the
* compiler replaces function addresses taken in C code with
* local jump table addresses, which breaks cross-module function
* address equality.
*/
#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_MODULES)
# define WARN_ON_FUNCTION_MISMATCH(x, fn) ({ 0; })
#else
# define WARN_ON_FUNCTION_MISMATCH(x, fn) WARN_ON_ONCE((x) != (fn))
#endif
#endif /* __ASSEMBLY__ */
#endif
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