v4.19.13 snapshot.
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
new file mode 100644
index 0000000..68bd882
--- /dev/null
+++ b/include/linux/kdb.h
@@ -0,0 +1,221 @@
+#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;
+
+/* 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 int kdb_printf_cpu;
+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_cpu(p);
+ 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 */