kgdb: core

/*

 * This provides the callbacks and functions that KGDB needs to share between

 * the core, I/O and arch-specific portions.

 *

 * Author: Amit Kale <amitkale@linsyssoft.com> and

 *         Tom Rini <trini@kernel.crashing.org>

 *

 * 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc.

 * This file is licensed under the terms of the GNU General Public License

 * version 2. This program is licensed "as is" without any warranty of any

 * kind, whether express or implied.

 */

#ifndef _KGDB_H_

#define _KGDB_H_

#include <linux/serial_8250.h>

#include <linux/linkage.h>

#include <linux/init.h>

#include <asm/atomic.h>

#include <asm/kgdb.h>

struct pt_regs;

/*

 *	kgdb_skipexception - Bail out of KGDB when we've been triggered.

 *	@exception: Exception vector number

 *	@regs: Current &struct pt_regs.

 *

 *	On some architectures we need to skip a breakpoint exception when

 *	it occurs after a breakpoint has been removed.

 */

extern int kgdb_skipexception(int exception, struct pt_regs *regs);

/*

 *	kgdb_post_primary_code - Save error vector/code numbers.

 *	@regs: Original pt_regs.

 *	@e_vector: Original error vector.

 *	@err_code: Original error code.

 *

 *	This is needed on architectures which support SMP and KGDB.

 *	This function is called after all the secondary cpus have been put

 *	to a know spin state and the primary CPU has control over KGDB.

 */

extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector,

				  int err_code);

/*

 *	kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.

 *	@regs: Current &struct pt_regs.

 *

 *	This function will be called if the particular architecture must

 *	disable hardware debugging while it is processing gdb packets or

 *	handling exception.

 */

extern void kgdb_disable_hw_debug(struct pt_regs *regs);

struct tasklet_struct;

struct task_struct;

struct uart_port;

/* To enter the debugger explicitly. */

void kgdb_breakpoint(void);

extern int kgdb_connected;

extern atomic_t			kgdb_setting_breakpoint;

extern atomic_t			kgdb_cpu_doing_single_step;

extern struct task_struct	*kgdb_usethread;

extern struct task_struct	*kgdb_contthread;

enum kgdb_bptype {

	BP_BREAKPOINT = 0,

	BP_HARDWARE_BREAKPOINT,

	BP_WRITE_WATCHPOINT,

	BP_READ_WATCHPOINT,

	BP_ACCESS_WATCHPOINT

};

enum kgdb_bpstate {

	BP_UNDEFINED = 0,

	BP_REMOVED,

	BP_SET,

	BP_ACTIVE

};

struct kgdb_bkpt {

	unsigned long		bpt_addr;

	unsigned char		saved_instr[BREAK_INSTR_SIZE];

	enum kgdb_bptype	type;

	enum kgdb_bpstate	state;

};

#ifndef KGDB_MAX_BREAKPOINTS

# define KGDB_MAX_BREAKPOINTS	1000

#endif

#define KGDB_HW_BREAKPOINT	1

/*

 * Functions each KGDB-supporting architecture must provide:

 */

/*

 *	kgdb_arch_init - Perform any architecture specific initalization.

 *

 *	This function will handle the initalization of any architecture

 *	specific callbacks.

 */

extern int kgdb_arch_init(void);

/*

 *	kgdb_arch_exit - Perform any architecture specific uninitalization.

 *

 *	This function will handle the uninitalization of any architecture

 *	specific callbacks, for dynamic registration and unregistration.

 */

extern void kgdb_arch_exit(void);

/*

 *	pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs

 *	@gdb_regs: A pointer to hold the registers in the order GDB wants.

 *	@regs: The &struct pt_regs of the current process.

 *

 *	Convert the pt_regs in @regs into the format for registers that

 *	GDB expects, stored in @gdb_regs.

 */

extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);

/*

 *	sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs

 *	@gdb_regs: A pointer to hold the registers in the order GDB wants.

 *	@p: The &struct task_struct of the desired process.

 *

 *	Convert the register values of the sleeping process in @p to

 *	the format that GDB expects.

 *	This function is called when kgdb does not have access to the

 *	&struct pt_regs and therefore it should fill the gdb registers

 *	@gdb_regs with what has	been saved in &struct thread_struct

 *	thread field during switch_to.

 */

extern void

sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);

/*

 *	gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.

 *	@gdb_regs: A pointer to hold the registers we've received from GDB.

 *	@regs: A pointer to a &struct pt_regs to hold these values in.

 *

 *	Convert the GDB regs in @gdb_regs into the pt_regs, and store them

 *	in @regs.

 */

extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);

/*

 *	kgdb_arch_handle_exception - Handle architecture specific GDB packets.

 *	@vector: The error vector of the exception that happened.

 *	@signo: The signal number of the exception that happened.

 *	@err_code: The error code of the exception that happened.

 *	@remcom_in_buffer: The buffer of the packet we have read.

 *	@remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.

 *	@regs: The &struct pt_regs of the current process.

 *

 *	This function MUST handle the 'c' and 's' command packets,

 *	as well packets to set / remove a hardware breakpoint, if used.

 *	If there are additional packets which the hardware needs to handle,

 *	they are handled here.  The code should return -1 if it wants to

 *	process more packets, and a %0 or %1 if it wants to exit from the

 *	kgdb callback.

 */

extern int

kgdb_arch_handle_exception(int vector, int signo, int err_code,

			   char *remcom_in_buffer,

			   char *remcom_out_buffer,

			   struct pt_regs *regs);

/*

 *	kgdb_roundup_cpus - Get other CPUs into a holding pattern

 *	@flags: Current IRQ state

 *

 *	On SMP systems, we need to get the attention of the other CPUs

 *	and get them be in a known state.  This should do what is needed

 *	to get the other CPUs to call kgdb_wait(). Note that on some arches,

 *	the NMI approach is not used for rounding up all the CPUs. For example,

 *	in case of MIPS, smp_call_function() is used to roundup CPUs. In

 *	this case, we have to make sure that interrupts are enabled before

 *	calling smp_call_function(). The argument to this function is

 *	the flags that will be used when restoring the interrupts. There is

 *	local_irq_save() call before kgdb_roundup_cpus().

 *

 *	On non-SMP systems, this is not called.

 */

extern void kgdb_roundup_cpus(unsigned long flags);

/* Optional functions. */

extern int kgdb_validate_break_address(unsigned long addr);

extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);

extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);

/*

 * struct kgdb_arch - Describe architecture specific values.

 * @gdb_bpt_instr: The instruction to trigger a breakpoint.

 * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.

 * @set_breakpoint: Allow an architecture to specify how to set a software

 * breakpoint.

 * @remove_breakpoint: Allow an architecture to specify how to remove a

 * software breakpoint.

 * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware

 * breakpoint.

 * @remove_hw_breakpoint: Allow an architecture to specify how to remove a

 * hardware breakpoint.

 * @remove_all_hw_break: Allow an architecture to specify how to remove all

 * hardware breakpoints.

 * @correct_hw_break: Allow an architecture to specify how to correct the

 * hardware debug registers.

 */

struct kgdb_arch {

	unsigned char		gdb_bpt_instr[BREAK_INSTR_SIZE];

	unsigned long		flags;

	int	(*set_breakpoint)(unsigned long, char *);

	int	(*remove_breakpoint)(unsigned long, char *);

	int	(*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);

	int	(*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);

	void	(*remove_all_hw_break)(void);

	void	(*correct_hw_break)(void);

};

/*

 * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.

 * @name: Name of the I/O driver.

 * @read_char: Pointer to a function that will return one char.

 * @write_char: Pointer to a function that will write one char.

 * @flush: Pointer to a function that will flush any pending writes.

 * @init: Pointer to a function that will initialize the device.

 * @pre_exception: Pointer to a function that will do any prep work for

 * the I/O driver.

 * @post_exception: Pointer to a function that will do any cleanup work

 * for the I/O driver.

 */

struct kgdb_io {

	const char		*name;

	int			(*read_char) (void);

	void			(*write_char) (u8);

	void			(*flush) (void);

	int			(*init) (void);

	void			(*pre_exception) (void);

	void			(*post_exception) (void);

};

extern struct kgdb_arch		arch_kgdb_ops;

extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);

extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);

extern int kgdb_hex2long(char **ptr, long *long_val);

extern int kgdb_mem2hex(char *mem, char *buf, int count);

extern int kgdb_hex2mem(char *buf, char *mem, int count);

extern int kgdb_isremovedbreak(unsigned long addr);

extern int

kgdb_handle_exception(int ex_vector, int signo, int err_code,

		      struct pt_regs *regs);

extern int kgdb_nmicallback(int cpu, void *regs);

extern int			kgdb_single_step;

extern atomic_t			kgdb_active;

#endif /* _KGDB_H_ */

obj-$(CONFIG_AUDITSYSCALL) += auditsc.o

obj-$(CONFIG_AUDIT_TREE) += audit_tree.o

obj-$(CONFIG_KPROBES) += kprobes.o

obj-$(CONFIG_KGDB) += kgdb.o

obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o

obj-$(CONFIG_GENERIC_HARDIRQS) += irq/

obj-$(CONFIG_SECCOMP) += seccomp.o

	  See Documentation/debugging-via-ohci1394.txt for more information.

source "samples/Kconfig"

source "lib/Kconfig.kgdb"

menuconfig KGDB

	bool "KGDB: kernel debugging with remote gdb"

	select FRAME_POINTER

	depends on HAVE_ARCH_KGDB

	depends on DEBUG_KERNEL && EXPERIMENTAL

	help

	  If you say Y here, it will be possible to remotely debug the

	  kernel using gdb.  Documentation of kernel debugger is available

	  at http://kgdb.sourceforge.net as well as in DocBook form

	  in Documentation/DocBook/.  If unsure, say N.

config HAVE_ARCH_KGDB_SHADOW_INFO

	bool

config HAVE_ARCH_KGDB

	bool

config KGDB_SERIAL_CONSOLE

	tristate "KGDB: use kgdb over the serial console"

	depends on KGDB

	select CONSOLE_POLL

	select MAGIC_SYSRQ

	default y

	help

	  Share a serial console with kgdb. Sysrq-g must be used

	  to break in initially.