@@ -186,6 +186,15 @@ config X86_DS_SELFTEST
config HAVE_MMIOTRACE_SUPPORT
def_bool y
+config X86_DECODER_SELFTEST
+ bool "x86 instruction decoder selftest"
+ depends on DEBUG_KERNEL
+ ---help---
+ Perform x86 instruction decoder selftests at build time.
+ This option is useful for checking the sanity of x86 instruction
+ decoder code.
+ If unsure, say "N".
+
#
# IO delay types:
#
@@ -154,6 +154,9 @@ all: bzImage
KBUILD_IMAGE := $(boot)/bzImage
bzImage: vmlinux
+ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
+ $(Q)$(MAKE) $(build)=arch/x86/tools posttest
+endif
$(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
$(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
$(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@
new file mode 100644
@@ -0,0 +1,15 @@
+PHONY += posttest
+quiet_cmd_posttest = TEST $@
+ cmd_posttest = $(OBJDUMP) -d $(objtree)/vmlinux | awk -f $(srctree)/arch/x86/tools/distill.awk | $(obj)/test_get_len
+
+posttest: $(obj)/test_get_len vmlinux
+ $(call cmd,posttest)
+
+hostprogs-y := test_get_len
+
+# -I needed for generated C source and C source which in the kernel tree.
+HOSTCFLAGS_test_get_len.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/
+
+# Dependancies 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 $(objtree)/arch/x86/lib/inat-tables.c
+
new file mode 100644
@@ -0,0 +1,42 @@
+#!/bin/awk -f
+# Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len
+# Distills the disassembly as follows:
+# - Removes all lines except the disassembled instructions.
+# - For instructions that exceed 1 line (7 bytes), crams all the hex bytes
+# into a single line.
+# - Remove bad(or prefix only) instructions
+
+BEGIN {
+ prev_addr = ""
+ prev_hex = ""
+ prev_mnemonic = ""
+ bad_expr = "(\\(bad\\)|^rex|^.byte|^rep(z|nz)$|^lock$|^es$|^cs$|^ss$|^ds$|^fs$|^gs$|^data(16|32)$|^addr(16|32|64))"
+ fwait_expr = "^9b "
+ fwait_str="9b\tfwait"
+}
+
+/^ *[0-9a-f]+:/ {
+ 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
+}
new file mode 100644
@@ -0,0 +1,113 @@
+/*
+ * 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>
+
+#ifdef __x86_64__
+#define CONFIG_X86_64
+#else
+#define CONFIG_X86_32
+#endif
+#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 void usage(void)
+{
+ fprintf(stderr, "Usage: objdump -d a.out | awk -f distill.awk |"
+ " ./test_get_len\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);
+}
+
+#define BUFSIZE 256
+
+int main(int argc, char **argv)
+{
+ char line[BUFSIZE];
+ unsigned char insn_buf[16];
+ struct insn insn;
+ int insns = 0;
+
+ prog = argv[0];
+ if (argc > 1)
+ usage();
+
+ while (fgets(line, BUFSIZE, stdin)) {
+ char copy[BUFSIZE], *s, *tab1, *tab2;
+ int nb = 0;
+ unsigned int b;
+
+ 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 */
+#ifdef __x86_64__
+ insn_init(&insn, insn_buf, 1);
+#else
+ insn_init(&insn, insn_buf, 0);
+#endif
+ insn_get_length(&insn);
+ if (insn.length != nb) {
+ fprintf(stderr, "Error: %s", line);
+ fprintf(stderr, "Error: objdump says %d bytes, but "
+ "insn_get_length() says %d (attr:%x)\n", nb,
+ insn.length, insn.attr);
+ exit(2);
+ }
+ }
+ fprintf(stderr, "Succeed: decoded and checked %d instructions\n",
+ insns);
+ return 0;
+}