linux/arch/x86/include/asm/kgdb.h
Jason Wessel f503b5ae53 x86,kgdb: Add low level debug hook
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a triple fault is
to have a low level "first opportunity handler" in the int3 exception
handler.

Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.

CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: H. Peter Anvin <hpa@zytor.com>
CC: x86@kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20 21:04:25 -05:00

83 lines
1.8 KiB
C

#ifndef _ASM_X86_KGDB_H
#define _ASM_X86_KGDB_H
/*
* Copyright (C) 2001-2004 Amit S. Kale
* Copyright (C) 2008 Wind River Systems, Inc.
*/
/*
* BUFMAX defines the maximum number of characters in inbound/outbound
* buffers at least NUMREGBYTES*2 are needed for register packets
* Longer buffer is needed to list all threads
*/
#define BUFMAX 1024
/*
* Note that this register image is in a different order than
* the register image that Linux produces at interrupt time.
*
* Linux's register image is defined by struct pt_regs in ptrace.h.
* Just why GDB uses a different order is a historical mystery.
*/
#ifdef CONFIG_X86_32
enum regnames {
GDB_AX, /* 0 */
GDB_CX, /* 1 */
GDB_DX, /* 2 */
GDB_BX, /* 3 */
GDB_SP, /* 4 */
GDB_BP, /* 5 */
GDB_SI, /* 6 */
GDB_DI, /* 7 */
GDB_PC, /* 8 also known as eip */
GDB_PS, /* 9 also known as eflags */
GDB_CS, /* 10 */
GDB_SS, /* 11 */
GDB_DS, /* 12 */
GDB_ES, /* 13 */
GDB_FS, /* 14 */
GDB_GS, /* 15 */
};
#define NUMREGBYTES ((GDB_GS+1)*4)
#else /* ! CONFIG_X86_32 */
enum regnames64 {
GDB_AX, /* 0 */
GDB_BX, /* 1 */
GDB_CX, /* 2 */
GDB_DX, /* 3 */
GDB_SI, /* 4 */
GDB_DI, /* 5 */
GDB_BP, /* 6 */
GDB_SP, /* 7 */
GDB_R8, /* 8 */
GDB_R9, /* 9 */
GDB_R10, /* 10 */
GDB_R11, /* 11 */
GDB_R12, /* 12 */
GDB_R13, /* 13 */
GDB_R14, /* 14 */
GDB_R15, /* 15 */
GDB_PC, /* 16 */
};
enum regnames32 {
GDB_PS = 34,
GDB_CS,
GDB_SS,
};
#define NUMREGBYTES ((GDB_SS+1)*4)
#endif /* CONFIG_X86_32 */
static inline void arch_kgdb_breakpoint(void)
{
asm(" int $3");
}
#define BREAK_INSTR_SIZE 1
#define CACHE_FLUSH_IS_SAFE 1
extern int kgdb_ll_trap(int cmd, const char *str,
struct pt_regs *regs, long err, int trap, int sig);
#endif /* _ASM_X86_KGDB_H */