Files
Syed Rameez Mustafa 1c014f321e kernel/lib: add additional debug capabilites for data corruption
Data corruptions in the kernel often end up in system crashes that
are easier to debug closer to the time of detection. Specifically,
if we do not panic immediately after lock or list corruptions have been
detected, the problem context is lost in the ensuing system mayhem.
Add support for allowing system crash immediately after such corruptions
are detected. The CONFIG option controls the enabling/disabling of the
feature.

Change-Id: I9b2eb62da506a13007acff63e85e9515145909ff
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
2013-07-17 15:53:24 -07:00

106 lines
3.1 KiB
C

#ifndef _LINUX_BUG_H
#define _LINUX_BUG_H
#include <asm/bug.h>
enum bug_trap_type {
BUG_TRAP_TYPE_NONE = 0,
BUG_TRAP_TYPE_WARN = 1,
BUG_TRAP_TYPE_BUG = 2,
};
struct pt_regs;
#ifdef __CHECKER__
#define BUILD_BUG_ON_NOT_POWER_OF_2(n)
#define BUILD_BUG_ON_ZERO(e) (0)
#define BUILD_BUG_ON_NULL(e) ((void*)0)
#define BUILD_BUG_ON(condition)
#define BUILD_BUG() (0)
#else /* __CHECKER__ */
/* Force a compilation error if a constant expression is not a power of 2 */
#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
/* Force a compilation error if condition is true, but also produce a
result (of value 0 and type size_t), so the expression can be used
e.g. in a structure initializer (or where-ever else comma expressions
aren't permitted). */
#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
/**
* BUILD_BUG_ON - break compile if a condition is true.
* @condition: the condition which the compiler should know is false.
*
* If you have some code which relies on certain constants being equal, or
* other compile-time-evaluated condition, you should use BUILD_BUG_ON to
* detect if someone changes it.
*
* The implementation uses gcc's reluctance to create a negative array, but
* gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
* to inline functions). So as a fallback we use the optimizer; if it can't
* prove the condition is false, it will cause a link error on the undefined
* "__build_bug_on_failed". This error message can be harder to track down
* though, hence the two different methods.
*/
#ifndef __OPTIMIZE__
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
#else
extern int __build_bug_on_failed;
#define BUILD_BUG_ON(condition) \
do { \
((void)sizeof(char[1 - 2*!!(condition)])); \
if (condition) __build_bug_on_failed = 1; \
} while(0)
#endif
/**
* BUILD_BUG - break compile if used.
*
* If you have some code that you expect the compiler to eliminate at
* build time, you should use BUILD_BUG to detect if it is
* unexpectedly used.
*/
#define BUILD_BUG() \
do { \
extern void __build_bug_failed(void) \
__linktime_error("BUILD_BUG failed"); \
__build_bug_failed(); \
} while (0)
#endif /* __CHECKER__ */
#ifdef CONFIG_GENERIC_BUG
#include <asm-generic/bug.h>
static inline int is_warning_bug(const struct bug_entry *bug)
{
return bug->flags & BUGFLAG_WARNING;
}
const struct bug_entry *find_bug(unsigned long bugaddr);
enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);
/* These are defined by the architecture */
int is_valid_bugaddr(unsigned long addr);
#else /* !CONFIG_GENERIC_BUG */
static inline enum bug_trap_type report_bug(unsigned long bug_addr,
struct pt_regs *regs)
{
return BUG_TRAP_TYPE_BUG;
}
#endif /* CONFIG_GENERIC_BUG */
#ifdef CONFIG_PANIC_ON_DATA_CORRUPTION
#define PANIC_CORRUPTION 1
#else
#define PANIC_CORRUPTION 0
#endif /* CONFIG_PANIC_ON_DATA_CORRUPTION */
#endif /* _LINUX_BUG_H */