File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/x86/include/asm/kgdb.h b/arch/x86/include/asm/kgdb.h
new file mode 100644
index 0000000..332f98c
--- /dev/null
+++ b/arch/x86/include/asm/kgdb.h
@@ -0,0 +1,89 @@
+#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 GDB_ORIG_AX		41
+#define DBG_MAX_REG_NUM		16
+#define NUMREGBYTES		((GDB_GS+1)*4)
+#else /* ! CONFIG_X86_32 */
+enum regnames {
+	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 */
+	GDB_PS,			/* 17 */
+	GDB_CS,			/* 18 */
+	GDB_SS,			/* 19 */
+	GDB_DS,			/* 20 */
+	GDB_ES,			/* 21 */
+	GDB_FS,			/* 22 */
+	GDB_GS,			/* 23 */
+};
+#define GDB_ORIG_AX		57
+#define DBG_MAX_REG_NUM		24
+/* 17 64 bit regs and 5 32 bit regs */
+#define NUMREGBYTES		((17 * 8) + (5 * 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
+#define GDB_ADJUSTS_BREAK_OFFSET
+
+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 */