M7350v1_en_gpl

kernel/arch/x86/tools/Makefile

@@ -0,0 +1,42 @@
+PHONY += posttest
+
+ifeq ($(KBUILD_VERBOSE),1)
+  posttest_verbose = -v
+else
+  posttest_verbose =
+endif
+
+ifeq ($(CONFIG_64BIT),y)
+  posttest_64bit = -y
+else
+  posttest_64bit = -n
+endif
+
+distill_awk = $(srctree)/arch/x86/tools/distill.awk
+chkobjdump = $(srctree)/arch/x86/tools/chkobjdump.awk
+
+quiet_cmd_posttest = TEST    $@
+      cmd_posttest = ($(OBJDUMP) -v | $(AWK) -f $(chkobjdump)) || $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(distill_awk) | $(obj)/test_get_len $(posttest_64bit) $(posttest_verbose)
+
+quiet_cmd_sanitytest = TEST    $@
+      cmd_sanitytest = $(obj)/insn_sanity $(posttest_64bit) -m 1000000
+
+posttest: $(obj)/test_get_len vmlinux $(obj)/insn_sanity
+	$(call cmd,posttest)
+	$(call cmd,sanitytest)
+
+hostprogs-y	+= test_get_len insn_sanity
+
+# -I needed for generated C source and C source which in the kernel tree.
+HOSTCFLAGS_test_get_len.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/
+
+HOSTCFLAGS_insn_sanity.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/
+
+# Dependencies are also needed.
+$(obj)/test_get_len.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c
+
+$(obj)/insn_sanity.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c
+
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include
+hostprogs-y	+= relocs
+relocs: $(obj)/relocs

kernel/arch/x86/tools/chkobjdump.awk

@@ -0,0 +1,33 @@
+# GNU objdump version checker
+#
+# Usage:
+# objdump -v | awk -f chkobjdump.awk
+BEGIN {
+	# objdump version 2.19 or later is OK for the test.
+	od_ver = 2;
+	od_sver = 19;
+}
+
+/^GNU objdump/ {
+	verstr = ""
+	for (i = 3; i <= NF; i++)
+		if (match($(i), "^[0-9]")) {
+			verstr = $(i);
+			break;
+		}
+	if (verstr == "") {
+		printf("Warning: Failed to find objdump version number.\n");
+		exit 0;
+	}
+	split(verstr, ver, ".");
+	if (ver[1] > od_ver ||
+	    (ver[1] == od_ver && ver[2] >= od_sver)) {
+		exit 1;
+	} else {
+		printf("Warning: objdump version %s is older than %d.%d\n",
+		       verstr, od_ver, od_sver);
+		print("Warning: Skipping posttest.");
+		# Logic is inverted, because we just skip test without error.
+		exit 0;
+	}
+}

kernel/arch/x86/tools/distill.awk

@@ -0,0 +1,47 @@
+#!/bin/awk -f
+# Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len
+# Distills the disassembly as follows:
+# - Removes all lines except the disassembled instructions.
+# - For instructions that exceed 1 line (7 bytes), crams all the hex bytes
+# into a single line.
+# - Remove bad(or prefix only) instructions
+
+BEGIN {
+	prev_addr = ""
+	prev_hex = ""
+	prev_mnemonic = ""
+	bad_expr = "(\\(bad\\)|^rex|^.byte|^rep(z|nz)$|^lock$|^es$|^cs$|^ss$|^ds$|^fs$|^gs$|^data(16|32)$|^addr(16|32|64))"
+	fwait_expr = "^9b "
+	fwait_str="9b\tfwait"
+}
+
+/^ *[0-9a-f]+ <[^>]*>:/ {
+	# Symbol entry
+	printf("%s%s\n", $2, $1)
+}
+
+/^ *[0-9a-f]+:/ {
+	if (split($0, field, "\t") < 3) {
+		# This is a continuation of the same insn.
+		prev_hex = prev_hex field[2]
+	} else {
+		# Skip bad instructions
+		if (match(prev_mnemonic, bad_expr))
+			prev_addr = ""
+		# Split fwait from other f* instructions
+		if (match(prev_hex, fwait_expr) && prev_mnemonic != "fwait") {
+			printf "%s\t%s\n", prev_addr, fwait_str
+			sub(fwait_expr, "", prev_hex)
+		}
+		if (prev_addr != "")
+			printf "%s\t%s\t%s\n", prev_addr, prev_hex, prev_mnemonic
+		prev_addr = field[1]
+		prev_hex = field[2]
+		prev_mnemonic = field[3]
+	}
+}
+
+END {
+	if (prev_addr != "")
+		printf "%s\t%s\t%s\n", prev_addr, prev_hex, prev_mnemonic
+}

kernel/arch/x86/tools/gen-insn-attr-x86.awk

@@ -0,0 +1,381 @@
+#!/bin/awk -f
+# gen-insn-attr-x86.awk: Instruction attribute table generator
+# Written by Masami Hiramatsu <mhiramat@redhat.com>
+#
+# Usage: awk -f gen-insn-attr-x86.awk x86-opcode-map.txt > inat-tables.c
+
+# Awk implementation sanity check
+function check_awk_implement() {
+	if (sprintf("%x", 0) != "0")
+		return "Your awk has a printf-format problem."
+	return ""
+}
+
+# Clear working vars
+function clear_vars() {
+	delete table
+	delete lptable2
+	delete lptable1
+	delete lptable3
+	eid = -1 # escape id
+	gid = -1 # group id
+	aid = -1 # AVX id
+	tname = ""
+}
+
+BEGIN {
+	# Implementation error checking
+	awkchecked = check_awk_implement()
+	if (awkchecked != "") {
+		print "Error: " awkchecked > "/dev/stderr"
+		print "Please try to use gawk." > "/dev/stderr"
+		exit 1
+	}
+
+	# Setup generating tables
+	print "/* x86 opcode map generated from x86-opcode-map.txt */"
+	print "/* Do not change this code. */\n"
+	ggid = 1
+	geid = 1
+	gaid = 0
+	delete etable
+	delete gtable
+	delete atable
+
+	opnd_expr = "^[A-Za-z/]"
+	ext_expr = "^\\("
+	sep_expr = "^\\|$"
+	group_expr = "^Grp[0-9A-Za-z]+"
+
+	imm_expr = "^[IJAOL][a-z]"
+	imm_flag["Ib"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
+	imm_flag["Jb"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
+	imm_flag["Iw"] = "INAT_MAKE_IMM(INAT_IMM_WORD)"
+	imm_flag["Id"] = "INAT_MAKE_IMM(INAT_IMM_DWORD)"
+	imm_flag["Iq"] = "INAT_MAKE_IMM(INAT_IMM_QWORD)"
+	imm_flag["Ap"] = "INAT_MAKE_IMM(INAT_IMM_PTR)"
+	imm_flag["Iz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)"
+	imm_flag["Jz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)"
+	imm_flag["Iv"] = "INAT_MAKE_IMM(INAT_IMM_VWORD)"
+	imm_flag["Ob"] = "INAT_MOFFSET"
+	imm_flag["Ov"] = "INAT_MOFFSET"
+	imm_flag["Lx"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
+
+	modrm_expr = "^([CDEGMNPQRSUVW/][a-z]+|NTA|T[012])"
+	force64_expr = "\\([df]64\\)"
+	rex_expr = "^REX(\\.[XRWB]+)*"
+	fpu_expr = "^ESC" # TODO
+
+	lprefix1_expr = "\\(66\\)"
+	lprefix2_expr = "\\(F3\\)"
+	lprefix3_expr = "\\(F2\\)"
+	max_lprefix = 4
+
+	# All opcodes starting with lower-case 'v' or with (v1) superscript
+	# accepts VEX prefix
+	vexok_opcode_expr = "^v.*"
+	vexok_expr = "\\(v1\\)"
+	# All opcodes with (v) superscript supports *only* VEX prefix
+	vexonly_expr = "\\(v\\)"
+
+	prefix_expr = "\\(Prefix\\)"
+	prefix_num["Operand-Size"] = "INAT_PFX_OPNDSZ"
+	prefix_num["REPNE"] = "INAT_PFX_REPNE"
+	prefix_num["REP/REPE"] = "INAT_PFX_REPE"
+	prefix_num["LOCK"] = "INAT_PFX_LOCK"
+	prefix_num["SEG=CS"] = "INAT_PFX_CS"
+	prefix_num["SEG=DS"] = "INAT_PFX_DS"
+	prefix_num["SEG=ES"] = "INAT_PFX_ES"
+	prefix_num["SEG=FS"] = "INAT_PFX_FS"
+	prefix_num["SEG=GS"] = "INAT_PFX_GS"
+	prefix_num["SEG=SS"] = "INAT_PFX_SS"
+	prefix_num["Address-Size"] = "INAT_PFX_ADDRSZ"
+	prefix_num["VEX+1byte"] = "INAT_PFX_VEX2"
+	prefix_num["VEX+2byte"] = "INAT_PFX_VEX3"
+
+	clear_vars()
+}
+
+function semantic_error(msg) {
+	print "Semantic error at " NR ": " msg > "/dev/stderr"
+	exit 1
+}
+
+function debug(msg) {
+	print "DEBUG: " msg
+}
+
+function array_size(arr,   i,c) {
+	c = 0
+	for (i in arr)
+		c++
+	return c
+}
+
+/^Table:/ {
+	print "/* " $0 " */"
+	if (tname != "")
+		semantic_error("Hit Table: before EndTable:.");
+}
+
+/^Referrer:/ {
+	if (NF != 1) {
+		# escape opcode table
+		ref = ""
+		for (i = 2; i <= NF; i++)
+			ref = ref $i
+		eid = escape[ref]
+		tname = sprintf("inat_escape_table_%d", eid)
+	}
+}
+
+/^AVXcode:/ {
+	if (NF != 1) {
+		# AVX/escape opcode table
+		aid = $2
+		if (gaid <= aid)
+			gaid = aid + 1
+		if (tname == "")	# AVX only opcode table
+			tname = sprintf("inat_avx_table_%d", $2)
+	}
+	if (aid == -1 && eid == -1)	# primary opcode table
+		tname = "inat_primary_table"
+}
+
+/^GrpTable:/ {
+	print "/* " $0 " */"
+	if (!($2 in group))
+		semantic_error("No group: " $2 )
+	gid = group[$2]
+	tname = "inat_group_table_" gid
+}
+
+function print_table(tbl,name,fmt,n)
+{
+	print "const insn_attr_t " name " = {"
+	for (i = 0; i < n; i++) {
+		id = sprintf(fmt, i)
+		if (tbl[id])
+			print "	[" id "] = " tbl[id] ","
+	}
+	print "};"
+}
+
+/^EndTable/ {
+	if (gid != -1) {
+		# print group tables
+		if (array_size(table) != 0) {
+			print_table(table, tname "[INAT_GROUP_TABLE_SIZE]",
+				    "0x%x", 8)
+			gtable[gid,0] = tname
+		}
+		if (array_size(lptable1) != 0) {
+			print_table(lptable1, tname "_1[INAT_GROUP_TABLE_SIZE]",
+				    "0x%x", 8)
+			gtable[gid,1] = tname "_1"
+		}
+		if (array_size(lptable2) != 0) {
+			print_table(lptable2, tname "_2[INAT_GROUP_TABLE_SIZE]",
+				    "0x%x", 8)
+			gtable[gid,2] = tname "_2"
+		}
+		if (array_size(lptable3) != 0) {
+			print_table(lptable3, tname "_3[INAT_GROUP_TABLE_SIZE]",
+				    "0x%x", 8)
+			gtable[gid,3] = tname "_3"
+		}
+	} else {
+		# print primary/escaped tables
+		if (array_size(table) != 0) {
+			print_table(table, tname "[INAT_OPCODE_TABLE_SIZE]",
+				    "0x%02x", 256)
+			etable[eid,0] = tname
+			if (aid >= 0)
+				atable[aid,0] = tname
+		}
+		if (array_size(lptable1) != 0) {
+			print_table(lptable1,tname "_1[INAT_OPCODE_TABLE_SIZE]",
+				    "0x%02x", 256)
+			etable[eid,1] = tname "_1"
+			if (aid >= 0)
+				atable[aid,1] = tname "_1"
+		}
+		if (array_size(lptable2) != 0) {
+			print_table(lptable2,tname "_2[INAT_OPCODE_TABLE_SIZE]",
+				    "0x%02x", 256)
+			etable[eid,2] = tname "_2"
+			if (aid >= 0)
+				atable[aid,2] = tname "_2"
+		}
+		if (array_size(lptable3) != 0) {
+			print_table(lptable3,tname "_3[INAT_OPCODE_TABLE_SIZE]",
+				    "0x%02x", 256)
+			etable[eid,3] = tname "_3"
+			if (aid >= 0)
+				atable[aid,3] = tname "_3"
+		}
+	}
+	print ""
+	clear_vars()
+}
+
+function add_flags(old,new) {
+	if (old && new)
+		return old " | " new
+	else if (old)
+		return old
+	else
+		return new
+}
+
+# convert operands to flags.
+function convert_operands(count,opnd,       i,j,imm,mod)
+{
+	imm = null
+	mod = null
+	for (j = 1; j <= count; j++) {
+		i = opnd[j]
+		if (match(i, imm_expr) == 1) {
+			if (!imm_flag[i])
+				semantic_error("Unknown imm opnd: " i)
+			if (imm) {
+				if (i != "Ib")
+					semantic_error("Second IMM error")
+				imm = add_flags(imm, "INAT_SCNDIMM")
+			} else
+				imm = imm_flag[i]
+		} else if (match(i, modrm_expr))
+			mod = "INAT_MODRM"
+	}
+	return add_flags(imm, mod)
+}
+
+/^[0-9a-f]+\:/ {
+	if (NR == 1)
+		next
+	# get index
+	idx = "0x" substr($1, 1, index($1,":") - 1)
+	if (idx in table)
+		semantic_error("Redefine " idx " in " tname)
+
+	# check if escaped opcode
+	if ("escape" == $2) {
+		if ($3 != "#")
+			semantic_error("No escaped name")
+		ref = ""
+		for (i = 4; i <= NF; i++)
+			ref = ref $i
+		if (ref in escape)
+			semantic_error("Redefine escape (" ref ")")
+		escape[ref] = geid
+		geid++
+		table[idx] = "INAT_MAKE_ESCAPE(" escape[ref] ")"
+		next
+	}
+
+	variant = null
+	# converts
+	i = 2
+	while (i <= NF) {
+		opcode = $(i++)
+		delete opnds
+		ext = null
+		flags = null
+		opnd = null
+		# parse one opcode
+		if (match($i, opnd_expr)) {
+			opnd = $i
+			count = split($(i++), opnds, ",")
+			flags = convert_operands(count, opnds)
+		}
+		if (match($i, ext_expr))
+			ext = $(i++)
+		if (match($i, sep_expr))
+			i++
+		else if (i < NF)
+			semantic_error($i " is not a separator")
+
+		# check if group opcode
+		if (match(opcode, group_expr)) {
+			if (!(opcode in group)) {
+				group[opcode] = ggid
+				ggid++
+			}
+			flags = add_flags(flags, "INAT_MAKE_GROUP(" group[opcode] ")")
+		}
+		# check force(or default) 64bit
+		if (match(ext, force64_expr))
+			flags = add_flags(flags, "INAT_FORCE64")
+
+		# check REX prefix
+		if (match(opcode, rex_expr))
+			flags = add_flags(flags, "INAT_MAKE_PREFIX(INAT_PFX_REX)")
+
+		# check coprocessor escape : TODO
+		if (match(opcode, fpu_expr))
+			flags = add_flags(flags, "INAT_MODRM")
+
+		# check VEX codes
+		if (match(ext, vexonly_expr))
+			flags = add_flags(flags, "INAT_VEXOK | INAT_VEXONLY")
+		else if (match(ext, vexok_expr) || match(opcode, vexok_opcode_expr))
+			flags = add_flags(flags, "INAT_VEXOK")
+
+		# check prefixes
+		if (match(ext, prefix_expr)) {
+			if (!prefix_num[opcode])
+				semantic_error("Unknown prefix: " opcode)
+			flags = add_flags(flags, "INAT_MAKE_PREFIX(" prefix_num[opcode] ")")
+		}
+		if (length(flags) == 0)
+			continue
+		# check if last prefix
+		if (match(ext, lprefix1_expr)) {
+			lptable1[idx] = add_flags(lptable1[idx],flags)
+			variant = "INAT_VARIANT"
+		} else if (match(ext, lprefix2_expr)) {
+			lptable2[idx] = add_flags(lptable2[idx],flags)
+			variant = "INAT_VARIANT"
+		} else if (match(ext, lprefix3_expr)) {
+			lptable3[idx] = add_flags(lptable3[idx],flags)
+			variant = "INAT_VARIANT"
+		} else {
+			table[idx] = add_flags(table[idx],flags)
+		}
+	}
+	if (variant)
+		table[idx] = add_flags(table[idx],variant)
+}
+
+END {
+	if (awkchecked != "")
+		exit 1
+	# print escape opcode map's array
+	print "/* Escape opcode map array */"
+	print "const insn_attr_t const *inat_escape_tables[INAT_ESC_MAX + 1]" \
+	      "[INAT_LSTPFX_MAX + 1] = {"
+	for (i = 0; i < geid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (etable[i,j])
+				print "	["i"]["j"] = "etable[i,j]","
+	print "};\n"
+	# print group opcode map's array
+	print "/* Group opcode map array */"
+	print "const insn_attr_t const *inat_group_tables[INAT_GRP_MAX + 1]"\
+	      "[INAT_LSTPFX_MAX + 1] = {"
+	for (i = 0; i < ggid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (gtable[i,j])
+				print "	["i"]["j"] = "gtable[i,j]","
+	print "};\n"
+	# print AVX opcode map's array
+	print "/* AVX opcode map array */"
+	print "const insn_attr_t const *inat_avx_tables[X86_VEX_M_MAX + 1]"\
+	      "[INAT_LSTPFX_MAX + 1] = {"
+	for (i = 0; i < gaid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (atable[i,j])
+				print "	["i"]["j"] = "atable[i,j]","
+	print "};"
+}
+

kernel/arch/x86/tools/insn_sanity.c

@@ -0,0 +1,275 @@
+/*
+ * x86 decoder sanity test - based on test_get_insn.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2009
+ * Copyright (C) Hitachi, Ltd., 2011
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define unlikely(cond) (cond)
+#define ARRAY_SIZE(a)	(sizeof(a)/sizeof(a[0]))
+
+#include <asm/insn.h>
+#include <inat.c>
+#include <insn.c>
+
+/*
+ * Test of instruction analysis against tampering.
+ * Feed random binary to instruction decoder and ensure not to
+ * access out-of-instruction-buffer.
+ */
+
+#define DEFAULT_MAX_ITER	10000
+#define INSN_NOP 0x90
+
+static const char	*prog;		/* Program name */
+static int		verbose;	/* Verbosity */
+static int		x86_64;		/* x86-64 bit mode flag */
+static unsigned int	seed;		/* Random seed */
+static unsigned long	iter_start;	/* Start of iteration number */
+static unsigned long	iter_end = DEFAULT_MAX_ITER;	/* End of iteration number */
+static FILE		*input_file;	/* Input file name */
+
+static void usage(const char *err)
+{
+	if (err)
+		fprintf(stderr, "Error: %s\n\n", err);
+	fprintf(stderr, "Usage: %s [-y|-n|-v] [-s seed[,no]] [-m max] [-i input]\n", prog);
+	fprintf(stderr, "\t-y	64bit mode\n");
+	fprintf(stderr, "\t-n	32bit mode\n");
+	fprintf(stderr, "\t-v	Verbosity(-vv dumps any decoded result)\n");
+	fprintf(stderr, "\t-s	Give a random seed (and iteration number)\n");
+	fprintf(stderr, "\t-m	Give a maximum iteration number\n");
+	fprintf(stderr, "\t-i	Give an input file with decoded binary\n");
+	exit(1);
+}
+
+static void dump_field(FILE *fp, const char *name, const char *indent,
+		       struct insn_field *field)
+{
+	fprintf(fp, "%s.%s = {\n", indent, name);
+	fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n",
+		indent, field->value, field->bytes[0], field->bytes[1],
+		field->bytes[2], field->bytes[3]);
+	fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent,
+		field->got, field->nbytes);
+}
+
+static void dump_insn(FILE *fp, struct insn *insn)
+{
+	fprintf(fp, "Instruction = {\n");
+	dump_field(fp, "prefixes", "\t",	&insn->prefixes);
+	dump_field(fp, "rex_prefix", "\t",	&insn->rex_prefix);
+	dump_field(fp, "vex_prefix", "\t",	&insn->vex_prefix);
+	dump_field(fp, "opcode", "\t",		&insn->opcode);
+	dump_field(fp, "modrm", "\t",		&insn->modrm);
+	dump_field(fp, "sib", "\t",		&insn->sib);
+	dump_field(fp, "displacement", "\t",	&insn->displacement);
+	dump_field(fp, "immediate1", "\t",	&insn->immediate1);
+	dump_field(fp, "immediate2", "\t",	&insn->immediate2);
+	fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n",
+		insn->attr, insn->opnd_bytes, insn->addr_bytes);
+	fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n",
+		insn->length, insn->x86_64, insn->kaddr);
+}
+
+static void dump_stream(FILE *fp, const char *msg, unsigned long nr_iter,
+			unsigned char *insn_buf, struct insn *insn)
+{
+	int i;
+
+	fprintf(fp, "%s:\n", msg);
+
+	dump_insn(fp, insn);
+
+	fprintf(fp, "You can reproduce this with below command(s);\n");
+
+	/* Input a decoded instruction sequence directly */
+	fprintf(fp, " $ echo ");
+	for (i = 0; i < MAX_INSN_SIZE; i++)
+		fprintf(fp, " %02x", insn_buf[i]);
+	fprintf(fp, " | %s -i -\n", prog);
+
+	if (!input_file) {
+		fprintf(fp, "Or \n");
+		/* Give a seed and iteration number */
+		fprintf(fp, " $ %s -s 0x%x,%lu\n", prog, seed, nr_iter);
+	}
+}
+
+static void init_random_seed(void)
+{
+	int fd;
+
+	fd = open("/dev/urandom", O_RDONLY);
+	if (fd < 0)
+		goto fail;
+
+	if (read(fd, &seed, sizeof(seed)) != sizeof(seed))
+		goto fail;
+
+	close(fd);
+	return;
+fail:
+	usage("Failed to open /dev/urandom");
+}
+
+/* Read given instruction sequence from the input file */
+static int read_next_insn(unsigned char *insn_buf)
+{
+	char buf[256]  = "", *tmp;
+	int i;
+
+	tmp = fgets(buf, ARRAY_SIZE(buf), input_file);
+	if (tmp == NULL || feof(input_file))
+		return 0;
+
+	for (i = 0; i < MAX_INSN_SIZE; i++) {
+		insn_buf[i] = (unsigned char)strtoul(tmp, &tmp, 16);
+		if (*tmp != ' ')
+			break;
+	}
+
+	return i;
+}
+
+static int generate_insn(unsigned char *insn_buf)
+{
+	int i;
+
+	if (input_file)
+		return read_next_insn(insn_buf);
+
+	/* Fills buffer with random binary up to MAX_INSN_SIZE */
+	for (i = 0; i < MAX_INSN_SIZE - 1; i += 2)
+		*(unsigned short *)(&insn_buf[i]) = random() & 0xffff;
+
+	while (i < MAX_INSN_SIZE)
+		insn_buf[i++] = random() & 0xff;
+
+	return i;
+}
+
+static void parse_args(int argc, char **argv)
+{
+	int c;
+	char *tmp = NULL;
+	int set_seed = 0;
+
+	prog = argv[0];
+	while ((c = getopt(argc, argv, "ynvs:m:i:")) != -1) {
+		switch (c) {
+		case 'y':
+			x86_64 = 1;
+			break;
+		case 'n':
+			x86_64 = 0;
+			break;
+		case 'v':
+			verbose++;
+			break;
+		case 'i':
+			if (strcmp("-", optarg) == 0)
+				input_file = stdin;
+			else
+				input_file = fopen(optarg, "r");
+			if (!input_file)
+				usage("Failed to open input file");
+			break;
+		case 's':
+			seed = (unsigned int)strtoul(optarg, &tmp, 0);
+			if (*tmp == ',') {
+				optarg = tmp + 1;
+				iter_start = strtoul(optarg, &tmp, 0);
+			}
+			if (*tmp != '\0' || tmp == optarg)
+				usage("Failed to parse seed");
+			set_seed = 1;
+			break;
+		case 'm':
+			iter_end = strtoul(optarg, &tmp, 0);
+			if (*tmp != '\0' || tmp == optarg)
+				usage("Failed to parse max_iter");
+			break;
+		default:
+			usage(NULL);
+		}
+	}
+
+	/* Check errors */
+	if (iter_end < iter_start)
+		usage("Max iteration number must be bigger than iter-num");
+
+	if (set_seed && input_file)
+		usage("Don't use input file (-i) with random seed (-s)");
+
+	/* Initialize random seed */
+	if (!input_file) {
+		if (!set_seed)	/* No seed is given */
+			init_random_seed();
+		srand(seed);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	struct insn insn;
+	int insns = 0;
+	int errors = 0;
+	unsigned long i;
+	unsigned char insn_buf[MAX_INSN_SIZE * 2];
+
+	parse_args(argc, argv);
+
+	/* Prepare stop bytes with NOPs */
+	memset(insn_buf + MAX_INSN_SIZE, INSN_NOP, MAX_INSN_SIZE);
+
+	for (i = 0; i < iter_end; i++) {
+		if (generate_insn(insn_buf) <= 0)
+			break;
+
+		if (i < iter_start)	/* Skip to given iteration number */
+			continue;
+
+		/* Decode an instruction */
+		insn_init(&insn, insn_buf, x86_64);
+		insn_get_length(&insn);
+
+		if (insn.next_byte <= insn.kaddr ||
+		    insn.kaddr + MAX_INSN_SIZE < insn.next_byte) {
+			/* Access out-of-range memory */
+			dump_stream(stderr, "Error: Found an access violation", i, insn_buf, &insn);
+			errors++;
+		} else if (verbose && !insn_complete(&insn))
+			dump_stream(stdout, "Info: Found an undecodable input", i, insn_buf, &insn);
+		else if (verbose >= 2)
+			dump_insn(stdout, &insn);
+		insns++;
+	}
+
+	fprintf(stdout, "%s: decoded and checked %d %s instructions with %d errors (seed:0x%x)\n", (errors) ? "Failure" : "Success", insns, (input_file) ? "given" : "random", errors, seed);
+
+	return errors ? 1 : 0;
+}

kernel/arch/x86/tools/relocs.c

@@ -0,0 +1,806 @@
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <elf.h>
+#include <byteswap.h>
+#define USE_BSD
+#include <endian.h>
+#include <regex.h>
+#include <tools/le_byteshift.h>
+
+static void die(char *fmt, ...);
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+static Elf32_Ehdr ehdr;
+static unsigned long reloc_count, reloc_idx;
+static unsigned long *relocs;
+static unsigned long reloc16_count, reloc16_idx;
+static unsigned long *relocs16;
+
+struct section {
+	Elf32_Shdr     shdr;
+	struct section *link;
+	Elf32_Sym      *symtab;
+	Elf32_Rel      *reltab;
+	char           *strtab;
+};
+static struct section *secs;
+
+enum symtype {
+	S_ABS,
+	S_REL,
+	S_SEG,
+	S_LIN,
+	S_NSYMTYPES
+};
+
+static const char * const sym_regex_kernel[S_NSYMTYPES] = {
+/*
+ * Following symbols have been audited. There values are constant and do
+ * not change if bzImage is loaded at a different physical address than
+ * the address for which it has been compiled. Don't warn user about
+ * absolute relocations present w.r.t these symbols.
+ */
+	[S_ABS] =
+	"^(xen_irq_disable_direct_reloc$|"
+	"xen_save_fl_direct_reloc$|"
+	"VDSO|"
+	"__crc_)",
+
+/*
+ * These symbols are known to be relative, even if the linker marks them
+ * as absolute (typically defined outside any section in the linker script.)
+ */
+	[S_REL] =
+	"^(__init_(begin|end)|"
+	"__x86_cpu_dev_(start|end)|"
+	"(__parainstructions|__alt_instructions)(|_end)|"
+	"(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
+	"_end)$"
+};
+
+
+static const char * const sym_regex_realmode[S_NSYMTYPES] = {
+/*
+ * These are 16-bit segment symbols when compiling 16-bit code.
+ */
+	[S_SEG] =
+	"^real_mode_seg$",
+
+/*
+ * These are offsets belonging to segments, as opposed to linear addresses,
+ * when compiling 16-bit code.
+ */
+	[S_LIN] =
+	"^pa_",
+};
+
+static const char * const *sym_regex;
+
+static regex_t sym_regex_c[S_NSYMTYPES];
+static int is_reloc(enum symtype type, const char *sym_name)
+{
+	return sym_regex[type] &&
+		!regexec(&sym_regex_c[type], sym_name, 0, NULL, 0);
+}
+
+static void regex_init(int use_real_mode)
+{
+        char errbuf[128];
+        int err;
+	int i;
+
+	if (use_real_mode)
+		sym_regex = sym_regex_realmode;
+	else
+		sym_regex = sym_regex_kernel;
+
+	for (i = 0; i < S_NSYMTYPES; i++) {
+		if (!sym_regex[i])
+			continue;
+
+		err = regcomp(&sym_regex_c[i], sym_regex[i],
+			      REG_EXTENDED|REG_NOSUB);
+
+		if (err) {
+			regerror(err, &sym_regex_c[i], errbuf, sizeof errbuf);
+			die("%s", errbuf);
+		}
+        }
+}
+
+static void die(char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	exit(1);
+}
+
+static const char *sym_type(unsigned type)
+{
+	static const char *type_name[] = {
+#define SYM_TYPE(X) [X] = #X
+		SYM_TYPE(STT_NOTYPE),
+		SYM_TYPE(STT_OBJECT),
+		SYM_TYPE(STT_FUNC),
+		SYM_TYPE(STT_SECTION),
+		SYM_TYPE(STT_FILE),
+		SYM_TYPE(STT_COMMON),
+		SYM_TYPE(STT_TLS),
+#undef SYM_TYPE
+	};
+	const char *name = "unknown sym type name";
+	if (type < ARRAY_SIZE(type_name)) {
+		name = type_name[type];
+	}
+	return name;
+}
+
+static const char *sym_bind(unsigned bind)
+{
+	static const char *bind_name[] = {
+#define SYM_BIND(X) [X] = #X
+		SYM_BIND(STB_LOCAL),
+		SYM_BIND(STB_GLOBAL),
+		SYM_BIND(STB_WEAK),
+#undef SYM_BIND
+	};
+	const char *name = "unknown sym bind name";
+	if (bind < ARRAY_SIZE(bind_name)) {
+		name = bind_name[bind];
+	}
+	return name;
+}
+
+static const char *sym_visibility(unsigned visibility)
+{
+	static const char *visibility_name[] = {
+#define SYM_VISIBILITY(X) [X] = #X
+		SYM_VISIBILITY(STV_DEFAULT),
+		SYM_VISIBILITY(STV_INTERNAL),
+		SYM_VISIBILITY(STV_HIDDEN),
+		SYM_VISIBILITY(STV_PROTECTED),
+#undef SYM_VISIBILITY
+	};
+	const char *name = "unknown sym visibility name";
+	if (visibility < ARRAY_SIZE(visibility_name)) {
+		name = visibility_name[visibility];
+	}
+	return name;
+}
+
+static const char *rel_type(unsigned type)
+{
+	static const char *type_name[] = {
+#define REL_TYPE(X) [X] = #X
+		REL_TYPE(R_386_NONE),
+		REL_TYPE(R_386_32),
+		REL_TYPE(R_386_PC32),
+		REL_TYPE(R_386_GOT32),
+		REL_TYPE(R_386_PLT32),
+		REL_TYPE(R_386_COPY),
+		REL_TYPE(R_386_GLOB_DAT),
+		REL_TYPE(R_386_JMP_SLOT),
+		REL_TYPE(R_386_RELATIVE),
+		REL_TYPE(R_386_GOTOFF),
+		REL_TYPE(R_386_GOTPC),
+		REL_TYPE(R_386_8),
+		REL_TYPE(R_386_PC8),
+		REL_TYPE(R_386_16),
+		REL_TYPE(R_386_PC16),
+#undef REL_TYPE
+	};
+	const char *name = "unknown type rel type name";
+	if (type < ARRAY_SIZE(type_name) && type_name[type]) {
+		name = type_name[type];
+	}
+	return name;
+}
+
+static const char *sec_name(unsigned shndx)
+{
+	const char *sec_strtab;
+	const char *name;
+	sec_strtab = secs[ehdr.e_shstrndx].strtab;
+	name = "<noname>";
+	if (shndx < ehdr.e_shnum) {
+		name = sec_strtab + secs[shndx].shdr.sh_name;
+	}
+	else if (shndx == SHN_ABS) {
+		name = "ABSOLUTE";
+	}
+	else if (shndx == SHN_COMMON) {
+		name = "COMMON";
+	}
+	return name;
+}
+
+static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
+{
+	const char *name;
+	name = "<noname>";
+	if (sym->st_name) {
+		name = sym_strtab + sym->st_name;
+	}
+	else {
+		name = sec_name(sym->st_shndx);
+	}
+	return name;
+}
+
+
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define le16_to_cpu(val) (val)
+#define le32_to_cpu(val) (val)
+#endif
+#if BYTE_ORDER == BIG_ENDIAN
+#define le16_to_cpu(val) bswap_16(val)
+#define le32_to_cpu(val) bswap_32(val)
+#endif
+
+static uint16_t elf16_to_cpu(uint16_t val)
+{
+	return le16_to_cpu(val);
+}
+
+static uint32_t elf32_to_cpu(uint32_t val)
+{
+	return le32_to_cpu(val);
+}
+
+static void read_ehdr(FILE *fp)
+{
+	if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
+		die("Cannot read ELF header: %s\n",
+			strerror(errno));
+	}
+	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
+		die("No ELF magic\n");
+	}
+	if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) {
+		die("Not a 32 bit executable\n");
+	}
+	if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
+		die("Not a LSB ELF executable\n");
+	}
+	if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
+		die("Unknown ELF version\n");
+	}
+	/* Convert the fields to native endian */
+	ehdr.e_type      = elf16_to_cpu(ehdr.e_type);
+	ehdr.e_machine   = elf16_to_cpu(ehdr.e_machine);
+	ehdr.e_version   = elf32_to_cpu(ehdr.e_version);
+	ehdr.e_entry     = elf32_to_cpu(ehdr.e_entry);
+	ehdr.e_phoff     = elf32_to_cpu(ehdr.e_phoff);
+	ehdr.e_shoff     = elf32_to_cpu(ehdr.e_shoff);
+	ehdr.e_flags     = elf32_to_cpu(ehdr.e_flags);
+	ehdr.e_ehsize    = elf16_to_cpu(ehdr.e_ehsize);
+	ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize);
+	ehdr.e_phnum     = elf16_to_cpu(ehdr.e_phnum);
+	ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize);
+	ehdr.e_shnum     = elf16_to_cpu(ehdr.e_shnum);
+	ehdr.e_shstrndx  = elf16_to_cpu(ehdr.e_shstrndx);
+
+	if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
+		die("Unsupported ELF header type\n");
+	}
+	if (ehdr.e_machine != EM_386) {
+		die("Not for x86\n");
+	}
+	if (ehdr.e_version != EV_CURRENT) {
+		die("Unknown ELF version\n");
+	}
+	if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) {
+		die("Bad Elf header size\n");
+	}
+	if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) {
+		die("Bad program header entry\n");
+	}
+	if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) {
+		die("Bad section header entry\n");
+	}
+	if (ehdr.e_shstrndx >= ehdr.e_shnum) {
+		die("String table index out of bounds\n");
+	}
+}
+
+static void read_shdrs(FILE *fp)
+{
+	int i;
+	Elf32_Shdr shdr;
+
+	secs = calloc(ehdr.e_shnum, sizeof(struct section));
+	if (!secs) {
+		die("Unable to allocate %d section headers\n",
+		    ehdr.e_shnum);
+	}
+	if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
+		die("Seek to %d failed: %s\n",
+			ehdr.e_shoff, strerror(errno));
+	}
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		if (fread(&shdr, sizeof shdr, 1, fp) != 1)
+			die("Cannot read ELF section headers %d/%d: %s\n",
+			    i, ehdr.e_shnum, strerror(errno));
+		sec->shdr.sh_name      = elf32_to_cpu(shdr.sh_name);
+		sec->shdr.sh_type      = elf32_to_cpu(shdr.sh_type);
+		sec->shdr.sh_flags     = elf32_to_cpu(shdr.sh_flags);
+		sec->shdr.sh_addr      = elf32_to_cpu(shdr.sh_addr);
+		sec->shdr.sh_offset    = elf32_to_cpu(shdr.sh_offset);
+		sec->shdr.sh_size      = elf32_to_cpu(shdr.sh_size);
+		sec->shdr.sh_link      = elf32_to_cpu(shdr.sh_link);
+		sec->shdr.sh_info      = elf32_to_cpu(shdr.sh_info);
+		sec->shdr.sh_addralign = elf32_to_cpu(shdr.sh_addralign);
+		sec->shdr.sh_entsize   = elf32_to_cpu(shdr.sh_entsize);
+		if (sec->shdr.sh_link < ehdr.e_shnum)
+			sec->link = &secs[sec->shdr.sh_link];
+	}
+
+}
+
+static void read_strtabs(FILE *fp)
+{
+	int i;
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		if (sec->shdr.sh_type != SHT_STRTAB) {
+			continue;
+		}
+		sec->strtab = malloc(sec->shdr.sh_size);
+		if (!sec->strtab) {
+			die("malloc of %d bytes for strtab failed\n",
+				sec->shdr.sh_size);
+		}
+		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
+			die("Seek to %d failed: %s\n",
+				sec->shdr.sh_offset, strerror(errno));
+		}
+		if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
+		    != sec->shdr.sh_size) {
+			die("Cannot read symbol table: %s\n",
+				strerror(errno));
+		}
+	}
+}
+
+static void read_symtabs(FILE *fp)
+{
+	int i,j;
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		if (sec->shdr.sh_type != SHT_SYMTAB) {
+			continue;
+		}
+		sec->symtab = malloc(sec->shdr.sh_size);
+		if (!sec->symtab) {
+			die("malloc of %d bytes for symtab failed\n",
+				sec->shdr.sh_size);
+		}
+		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
+			die("Seek to %d failed: %s\n",
+				sec->shdr.sh_offset, strerror(errno));
+		}
+		if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
+		    != sec->shdr.sh_size) {
+			die("Cannot read symbol table: %s\n",
+				strerror(errno));
+		}
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
+			Elf32_Sym *sym = &sec->symtab[j];
+			sym->st_name  = elf32_to_cpu(sym->st_name);
+			sym->st_value = elf32_to_cpu(sym->st_value);
+			sym->st_size  = elf32_to_cpu(sym->st_size);
+			sym->st_shndx = elf16_to_cpu(sym->st_shndx);
+		}
+	}
+}
+
+
+static void read_relocs(FILE *fp)
+{
+	int i,j;
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		if (sec->shdr.sh_type != SHT_REL) {
+			continue;
+		}
+		sec->reltab = malloc(sec->shdr.sh_size);
+		if (!sec->reltab) {
+			die("malloc of %d bytes for relocs failed\n",
+				sec->shdr.sh_size);
+		}
+		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
+			die("Seek to %d failed: %s\n",
+				sec->shdr.sh_offset, strerror(errno));
+		}
+		if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
+		    != sec->shdr.sh_size) {
+			die("Cannot read symbol table: %s\n",
+				strerror(errno));
+		}
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
+			Elf32_Rel *rel = &sec->reltab[j];
+			rel->r_offset = elf32_to_cpu(rel->r_offset);
+			rel->r_info   = elf32_to_cpu(rel->r_info);
+		}
+	}
+}
+
+
+static void print_absolute_symbols(void)
+{
+	int i;
+	printf("Absolute symbols\n");
+	printf(" Num:    Value Size  Type       Bind        Visibility  Name\n");
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		char *sym_strtab;
+		int j;
+
+		if (sec->shdr.sh_type != SHT_SYMTAB) {
+			continue;
+		}
+		sym_strtab = sec->link->strtab;
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
+			Elf32_Sym *sym;
+			const char *name;
+			sym = &sec->symtab[j];
+			name = sym_name(sym_strtab, sym);
+			if (sym->st_shndx != SHN_ABS) {
+				continue;
+			}
+			printf("%5d %08x %5d %10s %10s %12s %s\n",
+				j, sym->st_value, sym->st_size,
+				sym_type(ELF32_ST_TYPE(sym->st_info)),
+				sym_bind(ELF32_ST_BIND(sym->st_info)),
+				sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)),
+				name);
+		}
+	}
+	printf("\n");
+}
+
+static void print_absolute_relocs(void)
+{
+	int i, printed = 0;
+
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		struct section *sec = &secs[i];
+		struct section *sec_applies, *sec_symtab;
+		char *sym_strtab;
+		Elf32_Sym *sh_symtab;
+		int j;
+		if (sec->shdr.sh_type != SHT_REL) {
+			continue;
+		}
+		sec_symtab  = sec->link;
+		sec_applies = &secs[sec->shdr.sh_info];
+		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
+			continue;
+		}
+		sh_symtab  = sec_symtab->symtab;
+		sym_strtab = sec_symtab->link->strtab;
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
+			Elf32_Rel *rel;
+			Elf32_Sym *sym;
+			const char *name;
+			rel = &sec->reltab[j];
+			sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
+			name = sym_name(sym_strtab, sym);
+			if (sym->st_shndx != SHN_ABS) {
+				continue;
+			}
+
+			/* Absolute symbols are not relocated if bzImage is
+			 * loaded at a non-compiled address. Display a warning
+			 * to user at compile time about the absolute
+			 * relocations present.
+			 *
+			 * User need to audit the code to make sure
+			 * some symbols which should have been section
+			 * relative have not become absolute because of some
+			 * linker optimization or wrong programming usage.
+			 *
+			 * Before warning check if this absolute symbol
+			 * relocation is harmless.
+			 */
+			if (is_reloc(S_ABS, name) || is_reloc(S_REL, name))
+				continue;
+
+			if (!printed) {
+				printf("WARNING: Absolute relocations"
+					" present\n");
+				printf("Offset     Info     Type     Sym.Value "
+					"Sym.Name\n");
+				printed = 1;
+			}
+
+			printf("%08x %08x %10s %08x  %s\n",
+				rel->r_offset,
+				rel->r_info,
+				rel_type(ELF32_R_TYPE(rel->r_info)),
+				sym->st_value,
+				name);
+		}
+	}
+
+	if (printed)
+		printf("\n");
+}
+
+static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym),
+			int use_real_mode)
+{
+	int i;
+	/* Walk through the relocations */
+	for (i = 0; i < ehdr.e_shnum; i++) {
+		char *sym_strtab;
+		Elf32_Sym *sh_symtab;
+		struct section *sec_applies, *sec_symtab;
+		int j;
+		struct section *sec = &secs[i];
+
+		if (sec->shdr.sh_type != SHT_REL) {
+			continue;
+		}
+		sec_symtab  = sec->link;
+		sec_applies = &secs[sec->shdr.sh_info];
+		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
+			continue;
+		}
+		sh_symtab = sec_symtab->symtab;
+		sym_strtab = sec_symtab->link->strtab;
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
+			Elf32_Rel *rel;
+			Elf32_Sym *sym;
+			unsigned r_type;
+			const char *symname;
+			int shn_abs;
+
+			rel = &sec->reltab[j];
+			sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
+			r_type = ELF32_R_TYPE(rel->r_info);
+
+			shn_abs = sym->st_shndx == SHN_ABS;
+
+			switch (r_type) {
+			case R_386_NONE:
+			case R_386_PC32:
+			case R_386_PC16:
+			case R_386_PC8:
+				/*
+				 * NONE can be ignored and and PC relative
+				 * relocations don't need to be adjusted.
+				 */
+				break;
+
+			case R_386_16:
+				symname = sym_name(sym_strtab, sym);
+				if (!use_real_mode)
+					goto bad;
+				if (shn_abs) {
+					if (is_reloc(S_ABS, symname))
+						break;
+					else if (!is_reloc(S_SEG, symname))
+						goto bad;
+				} else {
+					if (is_reloc(S_LIN, symname))
+						goto bad;
+					else
+						break;
+				}
+				visit(rel, sym);
+				break;
+
+			case R_386_32:
+				symname = sym_name(sym_strtab, sym);
+				if (shn_abs) {
+					if (is_reloc(S_ABS, symname))
+						break;
+					else if (!is_reloc(S_REL, symname))
+						goto bad;
+				} else {
+					if (use_real_mode &&
+					    !is_reloc(S_LIN, symname))
+						break;
+				}
+				visit(rel, sym);
+				break;
+			default:
+				die("Unsupported relocation type: %s (%d)\n",
+				    rel_type(r_type), r_type);
+				break;
+			bad:
+				symname = sym_name(sym_strtab, sym);
+				die("Invalid %s %s relocation: %s\n",
+				    shn_abs ? "absolute" : "relative",
+				    rel_type(r_type), symname);
+			}
+		}
+	}
+}
+
+static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
+{
+	if (ELF32_R_TYPE(rel->r_info) == R_386_16)
+		reloc16_count++;
+	else
+		reloc_count++;
+}
+
+static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
+{
+	/* Remember the address that needs to be adjusted. */
+	if (ELF32_R_TYPE(rel->r_info) == R_386_16)
+		relocs16[reloc16_idx++] = rel->r_offset;
+	else
+		relocs[reloc_idx++] = rel->r_offset;
+}
+
+static int cmp_relocs(const void *va, const void *vb)
+{
+	const unsigned long *a, *b;
+	a = va; b = vb;
+	return (*a == *b)? 0 : (*a > *b)? 1 : -1;
+}
+
+static int write32(unsigned int v, FILE *f)
+{
+	unsigned char buf[4];
+
+	put_unaligned_le32(v, buf);
+	return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
+}
+
+static void emit_relocs(int as_text, int use_real_mode)
+{
+	int i;
+	/* Count how many relocations I have and allocate space for them. */
+	reloc_count = 0;
+	walk_relocs(count_reloc, use_real_mode);
+	relocs = malloc(reloc_count * sizeof(relocs[0]));
+	if (!relocs) {
+		die("malloc of %d entries for relocs failed\n",
+			reloc_count);
+	}
+
+	relocs16 = malloc(reloc16_count * sizeof(relocs[0]));
+	if (!relocs16) {
+		die("malloc of %d entries for relocs16 failed\n",
+			reloc16_count);
+	}
+	/* Collect up the relocations */
+	reloc_idx = 0;
+	walk_relocs(collect_reloc, use_real_mode);
+
+	if (reloc16_count && !use_real_mode)
+		die("Segment relocations found but --realmode not specified\n");
+
+	/* Order the relocations for more efficient processing */
+	qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs);
+	qsort(relocs16, reloc16_count, sizeof(relocs16[0]), cmp_relocs);
+
+	/* Print the relocations */
+	if (as_text) {
+		/* Print the relocations in a form suitable that
+		 * gas will like.
+		 */
+		printf(".section \".data.reloc\",\"a\"\n");
+		printf(".balign 4\n");
+		if (use_real_mode) {
+			printf("\t.long %lu\n", reloc16_count);
+			for (i = 0; i < reloc16_count; i++)
+				printf("\t.long 0x%08lx\n", relocs16[i]);
+			printf("\t.long %lu\n", reloc_count);
+			for (i = 0; i < reloc_count; i++) {
+				printf("\t.long 0x%08lx\n", relocs[i]);
+			}
+		} else {
+			/* Print a stop */
+			printf("\t.long 0x%08lx\n", (unsigned long)0);
+			for (i = 0; i < reloc_count; i++) {
+				printf("\t.long 0x%08lx\n", relocs[i]);
+			}
+		}
+
+		printf("\n");
+	}
+	else {
+		if (use_real_mode) {
+			write32(reloc16_count, stdout);
+			for (i = 0; i < reloc16_count; i++)
+				write32(relocs16[i], stdout);
+			write32(reloc_count, stdout);
+
+			/* Now print each relocation */
+			for (i = 0; i < reloc_count; i++)
+				write32(relocs[i], stdout);
+		} else {
+			/* Print a stop */
+			write32(0, stdout);
+
+			/* Now print each relocation */
+			for (i = 0; i < reloc_count; i++) {
+				write32(relocs[i], stdout);
+			}
+		}
+	}
+}
+
+static void usage(void)
+{
+	die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n");
+}
+
+int main(int argc, char **argv)
+{
+	int show_absolute_syms, show_absolute_relocs;
+	int as_text, use_real_mode;
+	const char *fname;
+	FILE *fp;
+	int i;
+
+	show_absolute_syms = 0;
+	show_absolute_relocs = 0;
+	as_text = 0;
+	use_real_mode = 0;
+	fname = NULL;
+	for (i = 1; i < argc; i++) {
+		char *arg = argv[i];
+		if (*arg == '-') {
+			if (strcmp(arg, "--abs-syms") == 0) {
+				show_absolute_syms = 1;
+				continue;
+			}
+			if (strcmp(arg, "--abs-relocs") == 0) {
+				show_absolute_relocs = 1;
+				continue;
+			}
+			if (strcmp(arg, "--text") == 0) {
+				as_text = 1;
+				continue;
+			}
+			if (strcmp(arg, "--realmode") == 0) {
+				use_real_mode = 1;
+				continue;
+			}
+		}
+		else if (!fname) {
+			fname = arg;
+			continue;
+		}
+		usage();
+	}
+	if (!fname) {
+		usage();
+	}
+	regex_init(use_real_mode);
+	fp = fopen(fname, "r");
+	if (!fp) {
+		die("Cannot open %s: %s\n",
+			fname, strerror(errno));
+	}
+	read_ehdr(fp);
+	read_shdrs(fp);
+	read_strtabs(fp);
+	read_symtabs(fp);
+	read_relocs(fp);
+	if (show_absolute_syms) {
+		print_absolute_symbols();
+		return 0;
+	}
+	if (show_absolute_relocs) {
+		print_absolute_relocs();
+		return 0;
+	}
+	emit_relocs(as_text, use_real_mode);
+	return 0;
+}

kernel/arch/x86/tools/test_get_len.c

@@ -0,0 +1,173 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2009
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+
+#define unlikely(cond) (cond)
+
+#include <asm/insn.h>
+#include <inat.c>
+#include <insn.c>
+
+/*
+ * Test of instruction analysis in general and insn_get_length() in
+ * particular.  See if insn_get_length() and the disassembler agree
+ * on the length of each instruction in an elf disassembly.
+ *
+ * Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len
+ */
+
+const char *prog;
+static int verbose;
+static int x86_64;
+
+static void usage(void)
+{
+	fprintf(stderr, "Usage: objdump -d a.out | awk -f distill.awk |"
+		" %s [-y|-n] [-v]\n", prog);
+	fprintf(stderr, "\t-y	64bit mode\n");
+	fprintf(stderr, "\t-n	32bit mode\n");
+	fprintf(stderr, "\t-v	verbose mode\n");
+	exit(1);
+}
+
+static void malformed_line(const char *line, int line_nr)
+{
+	fprintf(stderr, "%s: malformed line %d:\n%s", prog, line_nr, line);
+	exit(3);
+}
+
+static void dump_field(FILE *fp, const char *name, const char *indent,
+		       struct insn_field *field)
+{
+	fprintf(fp, "%s.%s = {\n", indent, name);
+	fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n",
+		indent, field->value, field->bytes[0], field->bytes[1],
+		field->bytes[2], field->bytes[3]);
+	fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent,
+		field->got, field->nbytes);
+}
+
+static void dump_insn(FILE *fp, struct insn *insn)
+{
+	fprintf(fp, "Instruction = {\n");
+	dump_field(fp, "prefixes", "\t",	&insn->prefixes);
+	dump_field(fp, "rex_prefix", "\t",	&insn->rex_prefix);
+	dump_field(fp, "vex_prefix", "\t",	&insn->vex_prefix);
+	dump_field(fp, "opcode", "\t",		&insn->opcode);
+	dump_field(fp, "modrm", "\t",		&insn->modrm);
+	dump_field(fp, "sib", "\t",		&insn->sib);
+	dump_field(fp, "displacement", "\t",	&insn->displacement);
+	dump_field(fp, "immediate1", "\t",	&insn->immediate1);
+	dump_field(fp, "immediate2", "\t",	&insn->immediate2);
+	fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n",
+		insn->attr, insn->opnd_bytes, insn->addr_bytes);
+	fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n",
+		insn->length, insn->x86_64, insn->kaddr);
+}
+
+static void parse_args(int argc, char **argv)
+{
+	int c;
+	prog = argv[0];
+	while ((c = getopt(argc, argv, "ynv")) != -1) {
+		switch (c) {
+		case 'y':
+			x86_64 = 1;
+			break;
+		case 'n':
+			x86_64 = 0;
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			usage();
+		}
+	}
+}
+
+#define BUFSIZE 256
+
+int main(int argc, char **argv)
+{
+	char line[BUFSIZE], sym[BUFSIZE] = "<unknown>";
+	unsigned char insn_buf[16];
+	struct insn insn;
+	int insns = 0;
+	int warnings = 0;
+
+	parse_args(argc, argv);
+
+	while (fgets(line, BUFSIZE, stdin)) {
+		char copy[BUFSIZE], *s, *tab1, *tab2;
+		int nb = 0;
+		unsigned int b;
+
+		if (line[0] == '<') {
+			/* Symbol line */
+			strcpy(sym, line);
+			continue;
+		}
+
+		insns++;
+		memset(insn_buf, 0, 16);
+		strcpy(copy, line);
+		tab1 = strchr(copy, '\t');
+		if (!tab1)
+			malformed_line(line, insns);
+		s = tab1 + 1;
+		s += strspn(s, " ");
+		tab2 = strchr(s, '\t');
+		if (!tab2)
+			malformed_line(line, insns);
+		*tab2 = '\0';	/* Characters beyond tab2 aren't examined */
+		while (s < tab2) {
+			if (sscanf(s, "%x", &b) == 1) {
+				insn_buf[nb++] = (unsigned char) b;
+				s += 3;
+			} else
+				break;
+		}
+		/* Decode an instruction */
+		insn_init(&insn, insn_buf, x86_64);
+		insn_get_length(&insn);
+		if (insn.length != nb) {
+			warnings++;
+			fprintf(stderr, "Warning: %s found difference at %s\n",
+				prog, sym);
+			fprintf(stderr, "Warning: %s", line);
+			fprintf(stderr, "Warning: objdump says %d bytes, but "
+				"insn_get_length() says %d\n", nb,
+				insn.length);
+			if (verbose)
+				dump_insn(stderr, &insn);
+		}
+	}
+	if (warnings)
+		fprintf(stderr, "Warning: decoded and checked %d"
+			" instructions with %d warnings\n", insns, warnings);
+	else
+		fprintf(stderr, "Succeed: decoded and checked %d"
+			" instructions\n", insns);
+	return 0;
+}