kernel-ark/include/linux/kdb.h
Daniel Thompson f7d4ca8bbf kdb: Avoid printing KERN_ levels to consoles
Currently when kdb traps printk messages then the raw log level prefix
(consisting of '\001' followed by a numeral) does not get stripped off
before the message is issued to the various I/O handlers supported by
kdb. This causes annoying visual noise as well as causing problems
grepping for ^. It is also a change of behaviour compared to normal usage
of printk() usage. For example <SysRq>-h ends up with different output to
that of kdb's "sr h".

This patch addresses the problem by stripping log levels from messages
before they are issued to the I/O handlers. printk() which can also
act as an i/o handler in some cases is special cased; if the caller
provided a log level then the prefix will be preserved when sent to
printk().

The addition of non-printable characters to the output of kdb commands is a
regression, albeit and extremely elderly one, introduced by commit
04d2c8c83d ("printk: convert the format for KERN_<LEVEL> to a 2 byte
pattern"). Note also that this patch does *not* restore the original
behaviour from v3.5. Instead it makes printk() from within a kdb command
display the message without any prefix (i.e. like printk() normally does).

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Joe Perches <joe@perches.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-02-19 12:39:02 -06:00

222 lines
7.3 KiB
C

#ifndef _KDB_H
#define _KDB_H
/*
* Kernel Debugger Architecture Independent Global Headers
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2000-2007 Silicon Graphics, Inc. All Rights Reserved.
* Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
* Copyright (C) 2009 Jason Wessel <jason.wessel@windriver.com>
*/
/* Shifted versions of the command enable bits are be used if the command
* has no arguments (see kdb_check_flags). This allows commands, such as
* go, to have different permissions depending upon whether it is called
* with an argument.
*/
#define KDB_ENABLE_NO_ARGS_SHIFT 10
typedef enum {
KDB_ENABLE_ALL = (1 << 0), /* Enable everything */
KDB_ENABLE_MEM_READ = (1 << 1),
KDB_ENABLE_MEM_WRITE = (1 << 2),
KDB_ENABLE_REG_READ = (1 << 3),
KDB_ENABLE_REG_WRITE = (1 << 4),
KDB_ENABLE_INSPECT = (1 << 5),
KDB_ENABLE_FLOW_CTRL = (1 << 6),
KDB_ENABLE_SIGNAL = (1 << 7),
KDB_ENABLE_REBOOT = (1 << 8),
/* User exposed values stop here, all remaining flags are
* exclusively used to describe a commands behaviour.
*/
KDB_ENABLE_ALWAYS_SAFE = (1 << 9),
KDB_ENABLE_MASK = (1 << KDB_ENABLE_NO_ARGS_SHIFT) - 1,
KDB_ENABLE_ALL_NO_ARGS = KDB_ENABLE_ALL << KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_MEM_READ_NO_ARGS = KDB_ENABLE_MEM_READ
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_MEM_WRITE_NO_ARGS = KDB_ENABLE_MEM_WRITE
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_REG_READ_NO_ARGS = KDB_ENABLE_REG_READ
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_REG_WRITE_NO_ARGS = KDB_ENABLE_REG_WRITE
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_INSPECT_NO_ARGS = KDB_ENABLE_INSPECT
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_FLOW_CTRL_NO_ARGS = KDB_ENABLE_FLOW_CTRL
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_SIGNAL_NO_ARGS = KDB_ENABLE_SIGNAL
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_REBOOT_NO_ARGS = KDB_ENABLE_REBOOT
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_ALWAYS_SAFE_NO_ARGS = KDB_ENABLE_ALWAYS_SAFE
<< KDB_ENABLE_NO_ARGS_SHIFT,
KDB_ENABLE_MASK_NO_ARGS = KDB_ENABLE_MASK << KDB_ENABLE_NO_ARGS_SHIFT,
KDB_REPEAT_NO_ARGS = 0x40000000, /* Repeat the command w/o arguments */
KDB_REPEAT_WITH_ARGS = 0x80000000, /* Repeat the command with args */
} kdb_cmdflags_t;
typedef int (*kdb_func_t)(int, const char **);
#ifdef CONFIG_KGDB_KDB
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/atomic.h>
#define KDB_POLL_FUNC_MAX 5
extern int kdb_poll_idx;
/*
* kdb_initial_cpu is initialized to -1, and is set to the cpu
* number whenever the kernel debugger is entered.
*/
extern int kdb_initial_cpu;
extern atomic_t kdb_event;
/* Types and messages used for dynamically added kdb shell commands */
#define KDB_MAXARGS 16 /* Maximum number of arguments to a function */
/* KDB return codes from a command or internal kdb function */
#define KDB_NOTFOUND (-1)
#define KDB_ARGCOUNT (-2)
#define KDB_BADWIDTH (-3)
#define KDB_BADRADIX (-4)
#define KDB_NOTENV (-5)
#define KDB_NOENVVALUE (-6)
#define KDB_NOTIMP (-7)
#define KDB_ENVFULL (-8)
#define KDB_ENVBUFFULL (-9)
#define KDB_TOOMANYBPT (-10)
#define KDB_TOOMANYDBREGS (-11)
#define KDB_DUPBPT (-12)
#define KDB_BPTNOTFOUND (-13)
#define KDB_BADMODE (-14)
#define KDB_BADINT (-15)
#define KDB_INVADDRFMT (-16)
#define KDB_BADREG (-17)
#define KDB_BADCPUNUM (-18)
#define KDB_BADLENGTH (-19)
#define KDB_NOBP (-20)
#define KDB_BADADDR (-21)
#define KDB_NOPERM (-22)
/*
* kdb_diemsg
*
* Contains a pointer to the last string supplied to the
* kernel 'die' panic function.
*/
extern const char *kdb_diemsg;
#define KDB_FLAG_EARLYKDB (1 << 0) /* set from boot parameter kdb=early */
#define KDB_FLAG_CATASTROPHIC (1 << 1) /* A catastrophic event has occurred */
#define KDB_FLAG_CMD_INTERRUPT (1 << 2) /* Previous command was interrupted */
#define KDB_FLAG_NOIPI (1 << 3) /* Do not send IPIs */
#define KDB_FLAG_NO_CONSOLE (1 << 5) /* No console is available,
* kdb is disabled */
#define KDB_FLAG_NO_VT_CONSOLE (1 << 6) /* No VT console is available, do
* not use keyboard */
#define KDB_FLAG_NO_I8042 (1 << 7) /* No i8042 chip is available, do
* not use keyboard */
extern int kdb_flags; /* Global flags, see kdb_state for per cpu state */
extern void kdb_save_flags(void);
extern void kdb_restore_flags(void);
#define KDB_FLAG(flag) (kdb_flags & KDB_FLAG_##flag)
#define KDB_FLAG_SET(flag) ((void)(kdb_flags |= KDB_FLAG_##flag))
#define KDB_FLAG_CLEAR(flag) ((void)(kdb_flags &= ~KDB_FLAG_##flag))
/*
* External entry point for the kernel debugger. The pt_regs
* at the time of entry are supplied along with the reason for
* entry to the kernel debugger.
*/
typedef enum {
KDB_REASON_ENTER = 1, /* KDB_ENTER() trap/fault - regs valid */
KDB_REASON_ENTER_SLAVE, /* KDB_ENTER_SLAVE() trap/fault - regs valid */
KDB_REASON_BREAK, /* Breakpoint inst. - regs valid */
KDB_REASON_DEBUG, /* Debug Fault - regs valid */
KDB_REASON_OOPS, /* Kernel Oops - regs valid */
KDB_REASON_SWITCH, /* CPU switch - regs valid*/
KDB_REASON_KEYBOARD, /* Keyboard entry - regs valid */
KDB_REASON_NMI, /* Non-maskable interrupt; regs valid */
KDB_REASON_RECURSE, /* Recursive entry to kdb;
* regs probably valid */
KDB_REASON_SSTEP, /* Single Step trap. - regs valid */
KDB_REASON_SYSTEM_NMI, /* In NMI due to SYSTEM cmd; regs valid */
} kdb_reason_t;
enum kdb_msgsrc {
KDB_MSGSRC_INTERNAL, /* direct call to kdb_printf() */
KDB_MSGSRC_PRINTK, /* trapped from printk() */
};
extern int kdb_trap_printk;
extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt,
va_list args);
extern __printf(1, 2) int kdb_printf(const char *, ...);
typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...);
extern void kdb_init(int level);
/* Access to kdb specific polling devices */
typedef int (*get_char_func)(void);
extern get_char_func kdb_poll_funcs[];
extern int kdb_get_kbd_char(void);
static inline
int kdb_process_cpu(const struct task_struct *p)
{
unsigned int cpu = task_thread_info(p)->cpu;
if (cpu > num_possible_cpus())
cpu = 0;
return cpu;
}
/* kdb access to register set for stack dumping */
extern struct pt_regs *kdb_current_regs;
#ifdef CONFIG_KALLSYMS
extern const char *kdb_walk_kallsyms(loff_t *pos);
#else /* ! CONFIG_KALLSYMS */
static inline const char *kdb_walk_kallsyms(loff_t *pos)
{
return NULL;
}
#endif /* ! CONFIG_KALLSYMS */
/* Dynamic kdb shell command registration */
extern int kdb_register(char *, kdb_func_t, char *, char *, short);
extern int kdb_register_flags(char *, kdb_func_t, char *, char *,
short, kdb_cmdflags_t);
extern int kdb_unregister(char *);
#else /* ! CONFIG_KGDB_KDB */
static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; }
static inline void kdb_init(int level) {}
static inline int kdb_register(char *cmd, kdb_func_t func, char *usage,
char *help, short minlen) { return 0; }
static inline int kdb_register_flags(char *cmd, kdb_func_t func, char *usage,
char *help, short minlen,
kdb_cmdflags_t flags) { return 0; }
static inline int kdb_unregister(char *cmd) { return 0; }
#endif /* CONFIG_KGDB_KDB */
enum {
KDB_NOT_INITIALIZED,
KDB_INIT_EARLY,
KDB_INIT_FULL,
};
extern int kdbgetintenv(const char *, int *);
extern int kdb_set(int, const char **);
#endif /* !_KDB_H */