Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

14 files changed, 2816 insertions, 0 deletions

diff --git a/arch/x86/tools/.gitignore b/arch/x86/tools/.gitignore
new file mode 100644
index 000000000..51d5c22b3
--- /dev/null
+++ b/arch/x86/tools/.gitignore
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+relocs
+vdso2c
diff --git a/arch/x86/tools/Makefile b/arch/x86/tools/Makefile
new file mode 100644
index 000000000..39a183fff
--- /dev/null
+++ b/arch/x86/tools/Makefile
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: GPL-2.0
+PHONY += posttest
+
+ifneq ($(findstring 1, $(KBUILD_VERBOSE)),)
+  posttest_verbose = -v
+else
+  posttest_verbose =
+endif
+
+ifeq ($(CONFIG_64BIT),y)
+  posttest_64bit = -y
+else
+  posttest_64bit = -n
+endif
+
+reformatter = $(srctree)/arch/x86/tools/objdump_reformat.awk
+chkobjdump = $(srctree)/arch/x86/tools/chkobjdump.awk
+
+quiet_cmd_posttest = TEST    $@
+      cmd_posttest = $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(reformatter) | $(obj)/insn_decoder_test $(posttest_64bit) $(posttest_verbose)
+
+quiet_cmd_sanitytest = TEST    $@
+      cmd_sanitytest = $(obj)/insn_sanity $(posttest_64bit) -m 1000000
+
+posttest: $(obj)/insn_decoder_test vmlinux $(obj)/insn_sanity
+	$(call cmd,posttest)
+	$(call cmd,sanitytest)
+
+hostprogs += insn_decoder_test insn_sanity
+
+# -I needed for generated C source and C source which in the kernel tree.
+HOSTCFLAGS_insn_decoder_test.o := -Wall -I$(srctree)/tools/arch/x86/lib/ -I$(srctree)/tools/arch/x86/include/ -I$(objtree)/arch/x86/lib/
+
+HOSTCFLAGS_insn_sanity.o := -Wall -I$(srctree)/tools/arch/x86/lib/ -I$(srctree)/tools/arch/x86/include/ -I$(objtree)/arch/x86/lib/
+
+# Dependencies are also needed.
+$(obj)/insn_decoder_test.o: $(srctree)/tools/arch/x86/lib/insn.c $(srctree)/tools/arch/x86/lib/inat.c $(srctree)/tools/arch/x86/include/asm/inat_types.h $(srctree)/tools/arch/x86/include/asm/inat.h $(srctree)/tools/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c
+
+$(obj)/insn_sanity.o: $(srctree)/tools/arch/x86/lib/insn.c $(srctree)/tools/arch/x86/lib/inat.c $(srctree)/tools/arch/x86/include/asm/inat_types.h $(srctree)/tools/arch/x86/include/asm/inat.h $(srctree)/tools/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c
+
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi \
+		    -I$(srctree)/arch/$(SUBARCH)/include/uapi
+
+hostprogs	+= relocs vdso2c
+relocs-objs	:= relocs_32.o relocs_64.o relocs_common.o
+
+always-y	:= $(hostprogs)
+
+PHONY += $(hostprogs)
+$(hostprogs): %: $(obj)/%
+	@:
diff --git a/arch/x86/tools/cpufeaturemasks.awk b/arch/x86/tools/cpufeaturemasks.awk
new file mode 100755
index 000000000..173d5bf2d
--- /dev/null
+++ b/arch/x86/tools/cpufeaturemasks.awk
@@ -0,0 +1,88 @@
+#!/usr/bin/awk
+#
+# Convert cpufeatures.h to a list of compile-time masks
+# Note: this blithely assumes that each word has at least one
+# feature defined in it; if not, something else is wrong!
+#
+
+BEGIN {
+	printf "#ifndef _ASM_X86_CPUFEATUREMASKS_H\n";
+	printf "#define _ASM_X86_CPUFEATUREMASKS_H\n\n";
+
+	file = 0
+}
+
+FNR == 1 {
+	++file;
+
+	# arch/x86/include/asm/cpufeatures.h
+	if (file == 1)
+		FS = "[ \t()*+]+";
+
+	# .config
+	if (file == 2)
+		FS = "=";
+}
+
+# Create a dictionary of sorts, containing all defined feature bits
+file == 1 && $1 ~ /^#define$/ && $2 ~ /^X86_FEATURE_/ {
+	nfeat = $3 * $4 + $5;
+	feat = $2;
+	sub(/^X86_FEATURE_/, "", feat);
+	feats[nfeat] = feat;
+}
+file == 1 && $1 ~ /^#define$/ && $2 == "NCAPINTS" {
+	ncapints = int($3);
+}
+
+# Create a dictionary featstat[REQUIRED|DISABLED, FEATURE_NAME] = on | off
+file == 2 && $1 ~ /^CONFIG_X86_(REQUIRED|DISABLED)_FEATURE_/ {
+	on = ($2 == "y");
+	if (split($1, fs, "CONFIG_X86_|_FEATURE_") == 3)
+		featstat[fs[2], fs[3]] = on;
+}
+
+END {
+	sets[1] = "REQUIRED";
+	sets[2] = "DISABLED";
+
+	for (ns in sets) {
+		s = sets[ns];
+
+		printf "/*\n";
+		printf " * %s features:\n", s;
+		printf " *\n";
+		fstr = "";
+		for (i = 0; i < ncapints; i++) {
+			mask = 0;
+			for (j = 0; j < 32; j++) {
+				feat = feats[i*32 + j];
+				if (featstat[s, feat]) {
+					nfstr = fstr " " feat;
+					if (length(nfstr) > 72) {
+						printf " *   %s\n", fstr;
+						nfstr = " " feat;
+					}
+					fstr = nfstr;
+					mask += (2 ^ j);
+				}
+			}
+			masks[i] = mask;
+		}
+		printf " *   %s\n */\n", fstr;
+
+		for (i = 0; i < ncapints; i++)
+			printf "#define %s_MASK%d\t0x%08xU\n", s, i, masks[i];
+
+		printf "\n#define %s_MASK_BIT_SET(x)\t\t\t\\\n", s;
+		printf "\t((\t\t\t\t\t";
+		for (i = 0; i < ncapints; i++) {
+			if (masks[i])
+				printf "\t\\\n\t\t((x) >> 5) == %2d ? %s_MASK%d :", i, s, i;
+		}
+		printf " 0\t\\\n";
+		printf "\t) & (1U << ((x) & 31)))\n\n";
+	}
+
+	printf "#endif /* _ASM_X86_CPUFEATUREMASKS_H */\n";
+}
diff --git a/arch/x86/tools/gen-insn-attr-x86.awk b/arch/x86/tools/gen-insn-attr-x86.awk
new file mode 100644
index 000000000..7ea1b75e5
--- /dev/null
+++ b/arch/x86/tools/gen-insn-attr-x86.awk
@@ -0,0 +1,505 @@
+#!/bin/awk -f
+# SPDX-License-Identifier: GPL-2.0
+# 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
+	xopid = -1 # XOP 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
+	gxopid = 0
+	delete etable
+	delete gtable
+	delete atable
+	delete xoptable
+
+	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)"
+	imm_flag["Lo"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)"
+
+	modrm_expr = "^([CDEGMNPQRSUVW/][a-z]+|NTA|T[012])"
+	force64_expr = "\\([df]64\\)"
+	invalid64_expr = "\\(i64\\)"
+	only64_expr = "\\(o64\\)"
+	rex_expr = "^((REX(\\.[XRWB]+)+)|(REX$))"
+	rex2_expr = "\\(REX2\\)"
+	no_rex2_expr = "\\(!REX2\\)"
+	fpu_expr = "^ESC" # TODO
+
+	lprefix1_expr = "\\((66|!F3)\\)"
+	lprefix2_expr = "\\(F3\\)"
+	lprefix3_expr = "\\((F2|!F3|66&F2)\\)"
+	lprefix_expr = "\\((66|F2|F3)\\)"
+	max_lprefix = 4
+
+	# All opcodes starting with lower-case 'v', 'k' or with (v1) superscript
+	# accepts VEX prefix
+	vexok_opcode_expr = "^[vk].*"
+	vexok_expr = "\\(v1\\)"
+	# All opcodes with (v) superscript supports *only* VEX prefix
+	vexonly_expr = "\\(v\\)"
+	# All opcodes with (ev) superscript supports *only* EVEX prefix
+	evexonly_expr = "\\(ev\\)"
+	# (es) is the same as (ev) but also "SCALABLE" i.e. W and pp determine operand size
+	evex_scalable_expr = "\\(es\\)"
+	# All opcodes in XOP table or with (xop) superscript accept XOP prefix
+	xopok_expr = "\\(xop\\)"
+
+	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["XACQUIRE"] = "INAT_PFX_REPNE"
+	prefix_num["XRELEASE"] = "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"
+	prefix_num["EVEX"] = "INAT_PFX_EVEX"
+	prefix_num["REX2"] = "INAT_PFX_REX2"
+	prefix_num["XOP"] = "INAT_PFX_XOP"
+
+	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
+		xopid = -1
+		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"
+}
+
+/^XOPcode:/ {
+	if (NF != 1) {
+		# XOP opcode table
+		xopid = $2
+		aid = -1
+		if (gxopid <= xopid)
+			gxopid = xopid + 1
+		if (tname == "")	# XOP only opcode table
+			tname = sprintf("inat_xop_table_%d", $2)
+	}
+	if (xopid == -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
+			else if (xopid >= 0)
+				xoptable[xopid] = 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 invalid in 64-bit (and no only64)
+		if (match(ext, invalid64_expr) &&
+		    !match($0, only64_expr))
+			flags = add_flags(flags, "INAT_INV64")
+
+		# check REX2 not allowed
+		if (match(ext, no_rex2_expr))
+			flags = add_flags(flags, "INAT_NO_REX2")
+
+		# 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, evexonly_expr))
+			flags = add_flags(flags, "INAT_VEXOK | INAT_EVEXONLY")
+		else if (match(ext, evex_scalable_expr))
+			flags = add_flags(flags, "INAT_VEXOK | INAT_EVEXONLY | INAT_EVEX_SCALABLE")
+		else 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")
+		else if (match(ext, xopok_expr) || xopid >= 0)
+			flags = add_flags(flags, "INAT_XOPOK")
+
+		# 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"
+		}
+		if (match(ext, lprefix2_expr)) {
+			lptable2[idx] = add_flags(lptable2[idx],flags)
+			variant = "INAT_VARIANT"
+		}
+		if (match(ext, lprefix3_expr)) {
+			lptable3[idx] = add_flags(lptable3[idx],flags)
+			variant = "INAT_VARIANT"
+		}
+		if (match(ext, rex2_expr))
+			table[idx] = add_flags(table[idx], "INAT_REX2_VARIANT")
+		if (!match(ext, lprefix_expr)){
+			table[idx] = add_flags(table[idx],flags)
+		}
+	}
+	if (variant)
+		table[idx] = add_flags(table[idx],variant)
+}
+
+END {
+	if (awkchecked != "")
+		exit 1
+
+	print "#ifndef __BOOT_COMPRESSED\n"
+
+	# 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 "};\n"
+
+	print "/* XOP opcode map array */"
+	print "const insn_attr_t * const inat_xop_tables[X86_XOP_M_MAX - X86_XOP_M_MIN + 1]" \
+	      " = {"
+	for (i = 0; i < gxopid; i++)
+		if (xoptable[i])
+			print "	["i"] = "xoptable[i]","
+	print "};"
+
+	print "#else /* !__BOOT_COMPRESSED */\n"
+
+	print "/* Escape opcode map array */"
+	print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \
+	      "[INAT_LSTPFX_MAX + 1];"
+	print ""
+
+	print "/* Group opcode map array */"
+	print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\
+	      "[INAT_LSTPFX_MAX + 1];"
+	print ""
+
+	print "/* AVX opcode map array */"
+	print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\
+	      "[INAT_LSTPFX_MAX + 1];"
+	print ""
+
+	print "/* XOP opcode map array */"
+	print "static const insn_attr_t *inat_xop_tables[X86_XOP_M_MAX - X86_XOP_M_MIN + 1];"
+	print ""
+
+	print "static void inat_init_tables(void)"
+	print "{"
+
+	# print escape opcode map's array
+	print "\t/* Print Escape opcode map array */"
+	for (i = 0; i < geid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (etable[i,j])
+				print "\tinat_escape_tables["i"]["j"] = "etable[i,j]";"
+	print ""
+
+	# print group opcode map's array
+	print "\t/* Print Group opcode map array */"
+	for (i = 0; i < ggid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (gtable[i,j])
+				print "\tinat_group_tables["i"]["j"] = "gtable[i,j]";"
+	print ""
+	# print AVX opcode map's array
+	print "\t/* Print AVX opcode map array */"
+	for (i = 0; i < gaid; i++)
+		for (j = 0; j < max_lprefix; j++)
+			if (atable[i,j])
+				print "\tinat_avx_tables["i"]["j"] = "atable[i,j]";"
+
+	print ""
+	print "\t/* Print XOP opcode map array */"
+	for (i = 0; i < gxopid; i++)
+		if (xoptable[i])
+			print "\tinat_xop_tables["i"] = "xoptable[i]";"
+
+	print "}"
+	print "#endif"
+}
+
diff --git a/arch/x86/tools/insn_decoder_test.c b/arch/x86/tools/insn_decoder_test.c
new file mode 100644
index 000000000..8bf15c4ae
--- /dev/null
+++ b/arch/x86/tools/insn_decoder_test.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Copyright (C) IBM Corporation, 2009
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <linux/kallsyms.h>
+
+#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 objdump_reformat.awk | ./insn_decoder_test
+ */
+
+const char *prog;
+static int verbose;
+static int x86_64;
+
+static void usage(void)
+{
+	fprintf(stderr, "Usage: objdump -d a.out | awk -f objdump_reformat.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: error: malformed line %d:\n%s",
+		prog, line_nr, line);
+	exit(3);
+}
+
+static void pr_warn(const char *fmt, ...)
+{
+	va_list ap;
+
+	fprintf(stderr, "%s: warning: ", prog);
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+}
+
+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 + KSYM_NAME_LEN)
+
+int main(int argc, char **argv)
+{
+	char line[BUFSIZE], sym[BUFSIZE] = "<unknown>";
+	unsigned char insn_buff[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, ret;
+		unsigned int b;
+
+		if (line[0] == '<') {
+			/* Symbol line */
+			strcpy(sym, line);
+			continue;
+		}
+
+		insns++;
+		memset(insn_buff, 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_buff[nb++] = (unsigned char) b;
+				s += 3;
+			} else
+				break;
+		}
+
+		/* Decode an instruction */
+		ret = insn_decode(&insn, insn_buff, sizeof(insn_buff),
+				  x86_64 ? INSN_MODE_64 : INSN_MODE_32);
+
+		if (ret < 0 || insn.length != nb) {
+			warnings++;
+			pr_warn("Found an x86 instruction decoder bug, "
+				"please report this.\n", sym);
+			pr_warn("%s", line);
+			pr_warn("objdump says %d bytes, but insn_get_length() "
+				"says %d\n", nb, insn.length);
+			if (verbose)
+				dump_insn(stderr, &insn);
+		}
+	}
+	if (warnings)
+		pr_warn("Decoded and checked %d instructions with %d "
+			"failures\n", insns, warnings);
+	else
+		fprintf(stdout, "  %s: success: Decoded and checked %d"
+			" instructions\n", prog, insns);
+	return 0;
+}
diff --git a/arch/x86/tools/insn_sanity.c b/arch/x86/tools/insn_sanity.c
new file mode 100644
index 000000000..e743f0ea0
--- /dev/null
+++ b/arch/x86/tools/insn_sanity.c
@@ -0,0 +1,265 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * x86 decoder sanity test - based on test_get_insn.c
+ *
+ * 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>
+#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, "%s: Error: %s\n\n", prog, 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_buff, 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_buff[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_buff)
+{
+	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_buff[i] = (unsigned char)strtoul(tmp, &tmp, 16);
+		if (*tmp != ' ')
+			break;
+	}
+
+	return i;
+}
+
+static int generate_insn(unsigned char *insn_buff)
+{
+	int i;
+
+	if (input_file)
+		return read_next_insn(insn_buff);
+
+	/* Fills buffer with random binary up to MAX_INSN_SIZE */
+	for (i = 0; i < MAX_INSN_SIZE - 1; i += 2)
+		*(unsigned short *)(&insn_buff[i]) = random() & 0xffff;
+
+	while (i < MAX_INSN_SIZE)
+		insn_buff[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)
+{
+	int insns = 0, ret;
+	struct insn insn;
+	int errors = 0;
+	unsigned long i;
+	unsigned char insn_buff[MAX_INSN_SIZE * 2];
+
+	parse_args(argc, argv);
+
+	/* Prepare stop bytes with NOPs */
+	memset(insn_buff + MAX_INSN_SIZE, INSN_NOP, MAX_INSN_SIZE);
+
+	for (i = 0; i < iter_end; i++) {
+		if (generate_insn(insn_buff) <= 0)
+			break;
+
+		if (i < iter_start)	/* Skip to given iteration number */
+			continue;
+
+		/* Decode an instruction */
+		ret = insn_decode(&insn, insn_buff, sizeof(insn_buff),
+				  x86_64 ? INSN_MODE_64 : INSN_MODE_32);
+
+		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_buff, &insn);
+			errors++;
+		} else if (verbose && ret < 0)
+			dump_stream(stdout, "Info: Found an undecodable input", i, insn_buff, &insn);
+		else if (verbose >= 2)
+			dump_insn(stdout, &insn);
+		insns++;
+	}
+
+	fprintf((errors) ? stderr : stdout,
+		"  %s: %s: Decoded and checked %d %s instructions with %d errors (seed:0x%x)\n",
+		prog,
+		(errors) ? "failure" : "success",
+		insns,
+		(input_file) ? "given" : "random",
+		errors,
+		seed);
+
+	return errors ? 1 : 0;
+}
diff --git a/arch/x86/tools/objdump_reformat.awk b/arch/x86/tools/objdump_reformat.awk
new file mode 100644
index 000000000..20b08a6c4
--- /dev/null
+++ b/arch/x86/tools/objdump_reformat.awk
@@ -0,0 +1,48 @@
+#!/bin/awk -f
+# SPDX-License-Identifier: GPL-2.0
+# Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test
+# Reformats 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\\)|<unknown>|^rex|^.byte|^rep(z|nz)$|^lock$|^es$|^cs$|^ss$|^ds$|^fs$|^gs$|^data(16|32)$|^addr(16|32|64))"
+	fwait_expr = "^9b[ \t]*fwait"
+	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
+}
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
new file mode 100644
index 000000000..5ea9bc7ee
--- /dev/null
+++ b/arch/x86/tools/relocs.c
@@ -0,0 +1,1079 @@
+// SPDX-License-Identifier: GPL-2.0
+/* This is included from relocs_32/64.c */
+
+#define ElfW(type)		_ElfW(ELF_BITS, type)
+#define _ElfW(bits, type)	__ElfW(bits, type)
+#define __ElfW(bits, type)	Elf##bits##_##type
+
+#define Elf_Addr		ElfW(Addr)
+#define Elf_Ehdr		ElfW(Ehdr)
+#define Elf_Phdr		ElfW(Phdr)
+#define Elf_Shdr		ElfW(Shdr)
+#define Elf_Sym			ElfW(Sym)
+
+static Elf_Ehdr			ehdr;
+static unsigned long		shnum;
+static unsigned int		shstrndx;
+static unsigned int		shsymtabndx;
+static unsigned int		shxsymtabndx;
+
+static int sym_index(Elf_Sym *sym);
+
+struct relocs {
+				uint32_t	*offset;
+				unsigned long	count;
+				unsigned long	size;
+};
+
+static struct relocs		relocs16;
+static struct relocs		relocs32;
+
+#if ELF_BITS == 64
+static struct relocs		relocs64;
+# define FMT PRIu64
+
+#ifndef R_X86_64_REX_GOTPCRELX
+# define R_X86_64_REX_GOTPCRELX 42
+#endif
+
+#else
+# define FMT PRIu32
+#endif
+
+struct section {
+				Elf_Shdr       shdr;
+				struct section *link;
+				Elf_Sym        *symtab;
+				Elf32_Word     *xsymtab;
+				Elf_Rel        *reltab;
+				char           *strtab;
+};
+static struct section		*secs;
+
+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$|"
+	"xen_elfnote_.+_offset$|"
+	"VDSO|"
+	"__kcfi_typeid_|"
+	"__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)|"
+	"__alt_instructions(_end)?|"
+	"(__iommu_table|__apicdrivers)(_end)?|"
+	"__(start|end)_pci_.*|"
+#if CONFIG_FW_LOADER
+	"__(start|end)_builtin_fw|"
+#endif
+	"__(start|stop)___ksymtab(_gpl)?|"
+	"__(start|stop)___kcrctab(_gpl)?|"
+	"__(start|stop)___param|"
+	"__(start|stop)___modver|"
+	"__(start|stop)___bug_table|"
+	"__tracedata_(start|end)|"
+	"__(start|stop)_notes|"
+	"__end_rodata|"
+	"__end_rodata_aligned|"
+	"__initramfs_start|"
+	"(jiffies|jiffies_64)|"
+#if ELF_BITS == 64
+	"__end_rodata_hpage_align|"
+#endif
+	"_end)$"
+};
+
+
+static const char * const sym_regex_realmode[S_NSYMTYPES] = {
+/*
+ * These symbols are known to be relative, even if the linker marks them
+ * as absolute (typically defined outside any section in the linker script.)
+ */
+	[S_REL] =
+	"^pa_",
+
+/*
+ * These are 16-bit segment symbols when compiling 16-bit code.
+ */
+	[S_SEG] =
+	"^real_mode_seg$",
+
+/*
+ * 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 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
+#if ELF_BITS == 64
+		REL_TYPE(R_X86_64_NONE),
+		REL_TYPE(R_X86_64_64),
+		REL_TYPE(R_X86_64_PC64),
+		REL_TYPE(R_X86_64_PC32),
+		REL_TYPE(R_X86_64_GOT32),
+		REL_TYPE(R_X86_64_PLT32),
+		REL_TYPE(R_X86_64_COPY),
+		REL_TYPE(R_X86_64_GLOB_DAT),
+		REL_TYPE(R_X86_64_JUMP_SLOT),
+		REL_TYPE(R_X86_64_RELATIVE),
+		REL_TYPE(R_X86_64_GOTPCREL),
+		REL_TYPE(R_X86_64_32),
+		REL_TYPE(R_X86_64_32S),
+		REL_TYPE(R_X86_64_16),
+		REL_TYPE(R_X86_64_PC16),
+		REL_TYPE(R_X86_64_8),
+		REL_TYPE(R_X86_64_PC8),
+		REL_TYPE(R_X86_64_REX_GOTPCRELX),
+#else
+		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),
+#endif
+#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[shstrndx].strtab;
+	name = "<noname>";
+
+	if (shndx < 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, Elf_Sym *sym)
+{
+	const char *name;
+	name = "<noname>";
+
+	if (sym->st_name)
+		name = sym_strtab + sym->st_name;
+	else
+		name = sec_name(sym_index(sym));
+
+	return name;
+}
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+# define le16_to_cpu(val)	(val)
+# define le32_to_cpu(val)	(val)
+# define le64_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)
+# define le64_to_cpu(val)	bswap_64(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);
+}
+
+#define elf_half_to_cpu(x)	elf16_to_cpu(x)
+#define elf_word_to_cpu(x)	elf32_to_cpu(x)
+
+#if ELF_BITS == 64
+static uint64_t elf64_to_cpu(uint64_t val)
+{
+        return le64_to_cpu(val);
+}
+# define elf_addr_to_cpu(x)	elf64_to_cpu(x)
+# define elf_off_to_cpu(x)	elf64_to_cpu(x)
+# define elf_xword_to_cpu(x)	elf64_to_cpu(x)
+#else
+# define elf_addr_to_cpu(x)	elf32_to_cpu(x)
+# define elf_off_to_cpu(x)	elf32_to_cpu(x)
+# define elf_xword_to_cpu(x)	elf32_to_cpu(x)
+#endif
+
+static int sym_index(Elf_Sym *sym)
+{
+	Elf_Sym *symtab = secs[shsymtabndx].symtab;
+	Elf32_Word *xsymtab = secs[shxsymtabndx].xsymtab;
+	unsigned long offset;
+	int index;
+
+	if (sym->st_shndx != SHN_XINDEX)
+		return sym->st_shndx;
+
+	/* calculate offset of sym from head of table. */
+	offset = (unsigned long)sym - (unsigned long)symtab;
+	index = offset / sizeof(*sym);
+
+	return elf32_to_cpu(xsymtab[index]);
+}
+
+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] != ELF_CLASS)
+		die("Not a %d bit executable\n", ELF_BITS);
+	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      = elf_half_to_cpu(ehdr.e_type);
+	ehdr.e_machine   = elf_half_to_cpu(ehdr.e_machine);
+	ehdr.e_version   = elf_word_to_cpu(ehdr.e_version);
+	ehdr.e_entry     = elf_addr_to_cpu(ehdr.e_entry);
+	ehdr.e_phoff     = elf_off_to_cpu(ehdr.e_phoff);
+	ehdr.e_shoff     = elf_off_to_cpu(ehdr.e_shoff);
+	ehdr.e_flags     = elf_word_to_cpu(ehdr.e_flags);
+	ehdr.e_ehsize    = elf_half_to_cpu(ehdr.e_ehsize);
+	ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize);
+	ehdr.e_phnum     = elf_half_to_cpu(ehdr.e_phnum);
+	ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize);
+	ehdr.e_shnum     = elf_half_to_cpu(ehdr.e_shnum);
+	ehdr.e_shstrndx  = elf_half_to_cpu(ehdr.e_shstrndx);
+
+	shnum = ehdr.e_shnum;
+	shstrndx = ehdr.e_shstrndx;
+
+	if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN))
+		die("Unsupported ELF header type\n");
+	if (ehdr.e_machine != ELF_MACHINE)
+		die("Not for %s\n", ELF_MACHINE_NAME);
+	if (ehdr.e_version != EV_CURRENT)
+		die("Unknown ELF version\n");
+	if (ehdr.e_ehsize != sizeof(Elf_Ehdr))
+		die("Bad ELF header size\n");
+	if (ehdr.e_phentsize != sizeof(Elf_Phdr))
+		die("Bad program header entry\n");
+	if (ehdr.e_shentsize != sizeof(Elf_Shdr))
+		die("Bad section header entry\n");
+
+
+	if (shnum == SHN_UNDEF || shstrndx == SHN_XINDEX) {
+		Elf_Shdr shdr;
+
+		if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0)
+			die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno));
+
+		if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
+			die("Cannot read initial ELF section header: %s\n", strerror(errno));
+
+		if (shnum == SHN_UNDEF)
+			shnum = elf_xword_to_cpu(shdr.sh_size);
+
+		if (shstrndx == SHN_XINDEX)
+			shstrndx = elf_word_to_cpu(shdr.sh_link);
+	}
+
+	if (shstrndx >= shnum)
+		die("String table index out of bounds\n");
+}
+
+static void read_shdrs(FILE *fp)
+{
+	int i;
+	Elf_Shdr shdr;
+
+	secs = calloc(shnum, sizeof(struct section));
+	if (!secs)
+		die("Unable to allocate %ld section headers\n", shnum);
+
+	if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0)
+		die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno));
+
+	for (i = 0; i < shnum; i++) {
+		struct section *sec = &secs[i];
+
+		if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
+			die("Cannot read ELF section headers %d/%ld: %s\n", i, shnum, strerror(errno));
+
+		sec->shdr.sh_name      = elf_word_to_cpu(shdr.sh_name);
+		sec->shdr.sh_type      = elf_word_to_cpu(shdr.sh_type);
+		sec->shdr.sh_flags     = elf_xword_to_cpu(shdr.sh_flags);
+		sec->shdr.sh_addr      = elf_addr_to_cpu(shdr.sh_addr);
+		sec->shdr.sh_offset    = elf_off_to_cpu(shdr.sh_offset);
+		sec->shdr.sh_size      = elf_xword_to_cpu(shdr.sh_size);
+		sec->shdr.sh_link      = elf_word_to_cpu(shdr.sh_link);
+		sec->shdr.sh_info      = elf_word_to_cpu(shdr.sh_info);
+		sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign);
+		sec->shdr.sh_entsize   = elf_xword_to_cpu(shdr.sh_entsize);
+		if (sec->shdr.sh_link < shnum)
+			sec->link = &secs[sec->shdr.sh_link];
+	}
+
+}
+
+static void read_strtabs(FILE *fp)
+{
+	int i;
+
+	for (i = 0; i < 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 %" FMT " bytes for strtab failed\n", sec->shdr.sh_size);
+
+		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
+			die("Seek to %" FMT " 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 < shnum; i++) {
+		struct section *sec = &secs[i];
+		int num_syms;
+
+		switch (sec->shdr.sh_type) {
+		case SHT_SYMTAB_SHNDX:
+			sec->xsymtab = malloc(sec->shdr.sh_size);
+			if (!sec->xsymtab)
+				die("malloc of %" FMT " bytes for xsymtab failed\n", sec->shdr.sh_size);
+
+			if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
+				die("Seek to %" FMT " failed: %s\n", sec->shdr.sh_offset, strerror(errno));
+
+			if (fread(sec->xsymtab, 1, sec->shdr.sh_size, fp) != sec->shdr.sh_size)
+				die("Cannot read extended symbol table: %s\n", strerror(errno));
+
+			shxsymtabndx = i;
+			continue;
+
+		case SHT_SYMTAB:
+			num_syms = sec->shdr.sh_size / sizeof(Elf_Sym);
+
+			sec->symtab = malloc(sec->shdr.sh_size);
+			if (!sec->symtab)
+				die("malloc of %" FMT " bytes for symtab failed\n", sec->shdr.sh_size);
+
+			if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
+				die("Seek to %" FMT " 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 < num_syms; j++) {
+				Elf_Sym *sym = &sec->symtab[j];
+
+				sym->st_name  = elf_word_to_cpu(sym->st_name);
+				sym->st_value = elf_addr_to_cpu(sym->st_value);
+				sym->st_size  = elf_xword_to_cpu(sym->st_size);
+				sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
+			}
+			shsymtabndx = i;
+			continue;
+
+		default:
+			continue;
+		}
+	}
+}
+
+
+static void read_relocs(FILE *fp)
+{
+	int i, j;
+
+	for (i = 0; i < shnum; i++) {
+		struct section *sec = &secs[i];
+
+		if (sec->shdr.sh_type != SHT_REL_TYPE)
+			continue;
+
+		sec->reltab = malloc(sec->shdr.sh_size);
+		if (!sec->reltab)
+			die("malloc of %" FMT " bytes for relocs failed\n", sec->shdr.sh_size);
+
+		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
+			die("Seek to %" FMT " 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(Elf_Rel); j++) {
+			Elf_Rel *rel = &sec->reltab[j];
+
+			rel->r_offset = elf_addr_to_cpu(rel->r_offset);
+			rel->r_info   = elf_xword_to_cpu(rel->r_info);
+#if (SHT_REL_TYPE == SHT_RELA)
+			rel->r_addend = elf_xword_to_cpu(rel->r_addend);
+#endif
+		}
+	}
+}
+
+
+static void print_absolute_symbols(void)
+{
+	int i;
+	const char *format;
+
+	if (ELF_BITS == 64)
+		format = "%5d %016"PRIx64" %5"PRId64" %10s %10s %12s %s\n";
+	else
+		format = "%5d %08"PRIx32"  %5"PRId32" %10s %10s %12s %s\n";
+
+	printf("Absolute symbols\n");
+	printf(" Num:    Value Size  Type       Bind        Visibility  Name\n");
+
+	for (i = 0; i < 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(Elf_Sym); j++) {
+			Elf_Sym *sym;
+			const char *name;
+
+			sym = &sec->symtab[j];
+			name = sym_name(sym_strtab, sym);
+
+			if (sym->st_shndx != SHN_ABS)
+				continue;
+
+			printf(format,
+				j, sym->st_value, sym->st_size,
+				sym_type(ELF_ST_TYPE(sym->st_info)),
+				sym_bind(ELF_ST_BIND(sym->st_info)),
+				sym_visibility(ELF_ST_VISIBILITY(sym->st_other)),
+				name);
+		}
+	}
+	printf("\n");
+}
+
+static void print_absolute_relocs(void)
+{
+	int i, printed = 0;
+	const char *format;
+
+	if (ELF_BITS == 64)
+		format = "%016"PRIx64" %016"PRIx64" %10s %016"PRIx64"  %s\n";
+	else
+		format = "%08"PRIx32" %08"PRIx32" %10s %08"PRIx32"  %s\n";
+
+	for (i = 0; i < shnum; i++) {
+		struct section *sec = &secs[i];
+		struct section *sec_applies, *sec_symtab;
+		char *sym_strtab;
+		Elf_Sym *sh_symtab;
+		int j;
+
+		if (sec->shdr.sh_type != SHT_REL_TYPE)
+			continue;
+
+		sec_symtab  = sec->link;
+		sec_applies = &secs[sec->shdr.sh_info];
+		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC))
+			continue;
+
+		/*
+		 * Do not perform relocations in .notes section; any
+		 * values there are meant for pre-boot consumption (e.g.
+		 * startup_xen).
+		 */
+		if (sec_applies->shdr.sh_type == SHT_NOTE)
+			continue;
+
+		sh_symtab  = sec_symtab->symtab;
+		sym_strtab = sec_symtab->link->strtab;
+
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
+			Elf_Rel *rel;
+			Elf_Sym *sym;
+			const char *name;
+
+			rel = &sec->reltab[j];
+			sym = &sh_symtab[ELF_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(format,
+				rel->r_offset,
+				rel->r_info,
+				rel_type(ELF_R_TYPE(rel->r_info)),
+				sym->st_value,
+				name);
+		}
+	}
+
+	if (printed)
+		printf("\n");
+}
+
+static void add_reloc(struct relocs *r, uint32_t offset)
+{
+	if (r->count == r->size) {
+		unsigned long newsize = r->size + 50000;
+		void *mem = realloc(r->offset, newsize * sizeof(r->offset[0]));
+
+		if (!mem)
+			die("realloc of %ld entries for relocs failed\n", newsize);
+
+		r->offset = mem;
+		r->size = newsize;
+	}
+	r->offset[r->count++] = offset;
+}
+
+static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
+			Elf_Sym *sym, const char *symname))
+{
+	int i;
+
+	/* Walk through the relocations */
+	for (i = 0; i < shnum; i++) {
+		char *sym_strtab;
+		Elf_Sym *sh_symtab;
+		struct section *sec_applies, *sec_symtab;
+		int j;
+		struct section *sec = &secs[i];
+
+		if (sec->shdr.sh_type != SHT_REL_TYPE)
+			continue;
+
+		sec_symtab  = sec->link;
+		sec_applies = &secs[sec->shdr.sh_info];
+		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC))
+			continue;
+
+		/*
+		 * Do not perform relocations in .notes sections; any
+		 * values there are meant for pre-boot consumption (e.g.
+		 * startup_xen).
+		 */
+		if (sec_applies->shdr.sh_type == SHT_NOTE)
+			continue;
+
+		sh_symtab = sec_symtab->symtab;
+		sym_strtab = sec_symtab->link->strtab;
+
+		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
+			Elf_Rel *rel = &sec->reltab[j];
+			Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
+			const char *symname = sym_name(sym_strtab, sym);
+
+			process(sec, rel, sym, symname);
+		}
+	}
+}
+
+#if ELF_BITS == 64
+
+static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
+		      const char *symname)
+{
+	unsigned r_type = ELF64_R_TYPE(rel->r_info);
+	ElfW(Addr) offset = rel->r_offset;
+	int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+	if (sym->st_shndx == SHN_UNDEF)
+		return 0;
+
+	switch (r_type) {
+	case R_X86_64_NONE:
+		/* NONE can be ignored. */
+		break;
+
+	case R_X86_64_PC32:
+	case R_X86_64_PLT32:
+	case R_X86_64_REX_GOTPCRELX:
+		/*
+		 * PC relative relocations don't need to be adjusted.
+		 *
+		 * NB: R_X86_64_PLT32 can be treated as R_X86_64_PC32.
+		 */
+		break;
+
+	case R_X86_64_PC64:
+		/*
+		 * Only used by jump labels
+		 */
+		break;
+
+	case R_X86_64_32:
+	case R_X86_64_32S:
+	case R_X86_64_64:
+		if (shn_abs) {
+			/*
+			 * Whitelisted absolute symbols do not require
+			 * relocation.
+			 */
+			if (is_reloc(S_ABS, symname))
+				break;
+
+			die("Invalid absolute %s relocation: %s\n", rel_type(r_type), symname);
+			break;
+		}
+
+		/*
+		 * Relocation offsets for 64 bit kernels are output
+		 * as 32 bits and sign extended back to 64 bits when
+		 * the relocations are processed.
+		 * Make sure that the offset will fit.
+		 */
+		if ((int32_t)offset != (int64_t)offset)
+			die("Relocation offset doesn't fit in 32 bits\n");
+
+		if (r_type == R_X86_64_64)
+			add_reloc(&relocs64, offset);
+		else
+			add_reloc(&relocs32, offset);
+		break;
+
+	default:
+		die("Unsupported relocation type: %s (%d)\n", rel_type(r_type), r_type);
+		break;
+	}
+
+	return 0;
+}
+
+#else
+
+static int do_reloc32(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
+		      const char *symname)
+{
+	unsigned r_type = ELF32_R_TYPE(rel->r_info);
+	int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+	switch (r_type) {
+	case R_386_NONE:
+	case R_386_PC32:
+	case R_386_PC16:
+	case R_386_PC8:
+	case R_386_PLT32:
+		/*
+		 * NONE can be ignored and PC relative relocations don't need
+		 * to be adjusted. Because sym must be defined, R_386_PLT32 can
+		 * be treated the same way as R_386_PC32.
+		 */
+		break;
+
+	case R_386_32:
+		if (shn_abs) {
+			/*
+			 * Whitelisted absolute symbols do not require
+			 * relocation.
+			 */
+			if (is_reloc(S_ABS, symname))
+				break;
+
+			die("Invalid absolute %s relocation: %s\n", rel_type(r_type), symname);
+			break;
+		}
+
+		add_reloc(&relocs32, rel->r_offset);
+		break;
+
+	default:
+		die("Unsupported relocation type: %s (%d)\n", rel_type(r_type), r_type);
+		break;
+	}
+
+	return 0;
+}
+
+static int do_reloc_real(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, const char *symname)
+{
+	unsigned r_type = ELF32_R_TYPE(rel->r_info);
+	int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+	switch (r_type) {
+	case R_386_NONE:
+	case R_386_PC32:
+	case R_386_PC16:
+	case R_386_PC8:
+	case R_386_PLT32:
+		/*
+		 * NONE can be ignored and PC relative relocations don't need
+		 * to be adjusted. Because sym must be defined, R_386_PLT32 can
+		 * be treated the same way as R_386_PC32.
+		 */
+		break;
+
+	case R_386_16:
+		if (shn_abs) {
+			/*
+			 * Whitelisted absolute symbols do not require
+			 * relocation.
+			 */
+			if (is_reloc(S_ABS, symname))
+				break;
+
+			if (is_reloc(S_SEG, symname)) {
+				add_reloc(&relocs16, rel->r_offset);
+				break;
+			}
+		} else {
+			if (!is_reloc(S_LIN, symname))
+				break;
+		}
+		die("Invalid %s %s relocation: %s\n", shn_abs ? "absolute" : "relative", rel_type(r_type), symname);
+		break;
+
+	case R_386_32:
+		if (shn_abs) {
+			/*
+			 * Whitelisted absolute symbols do not require
+			 * relocation.
+			 */
+			if (is_reloc(S_ABS, symname))
+				break;
+
+			if (is_reloc(S_REL, symname)) {
+				add_reloc(&relocs32, rel->r_offset);
+				break;
+			}
+		} else {
+			if (is_reloc(S_LIN, symname))
+				add_reloc(&relocs32, rel->r_offset);
+			break;
+		}
+		die("Invalid %s %s relocation: %s\n", shn_abs ? "absolute" : "relative", rel_type(r_type), symname);
+		break;
+
+	default:
+		die("Unsupported relocation type: %s (%d)\n", rel_type(r_type), r_type);
+		break;
+	}
+
+	return 0;
+}
+
+#endif
+
+static int cmp_relocs(const void *va, const void *vb)
+{
+	const uint32_t *a, *b;
+
+	a = va;
+	b = vb;
+
+	return (*a == *b)? 0 : (*a > *b)? 1 : -1;
+}
+
+static void sort_relocs(struct relocs *r)
+{
+	if (r->count)
+		qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs);
+}
+
+static int write32(uint32_t v, FILE *f)
+{
+	unsigned char buf[4];
+
+	put_unaligned_le32(v, buf);
+
+	return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
+}
+
+static int write32_as_text(uint32_t v, FILE *f)
+{
+	return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1;
+}
+
+static void emit_relocs(int as_text, int use_real_mode)
+{
+	int i;
+	int (*write_reloc)(uint32_t, FILE *) = write32;
+	int (*do_reloc)(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, const char *symname);
+
+#if ELF_BITS == 64
+	if (!use_real_mode)
+		do_reloc = do_reloc64;
+	else
+		die("--realmode not valid for a 64-bit ELF file");
+#else
+	if (!use_real_mode)
+		do_reloc = do_reloc32;
+	else
+		do_reloc = do_reloc_real;
+#endif
+
+	/* Collect up the relocations */
+	walk_relocs(do_reloc);
+
+	if (relocs16.count && !use_real_mode)
+		die("Segment relocations found but --realmode not specified\n");
+
+	/* Order the relocations for more efficient processing */
+	sort_relocs(&relocs32);
+#if ELF_BITS == 64
+	sort_relocs(&relocs64);
+#else
+	sort_relocs(&relocs16);
+#endif
+
+	/* 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");
+		write_reloc = write32_as_text;
+	}
+
+	if (use_real_mode) {
+		write_reloc(relocs16.count, stdout);
+		for (i = 0; i < relocs16.count; i++)
+			write_reloc(relocs16.offset[i], stdout);
+
+		write_reloc(relocs32.count, stdout);
+		for (i = 0; i < relocs32.count; i++)
+			write_reloc(relocs32.offset[i], stdout);
+	} else {
+#if ELF_BITS == 64
+		/* Print a stop */
+		write_reloc(0, stdout);
+
+		/* Now print each relocation */
+		for (i = 0; i < relocs64.count; i++)
+			write_reloc(relocs64.offset[i], stdout);
+#endif
+
+		/* Print a stop */
+		write_reloc(0, stdout);
+
+		/* Now print each relocation */
+		for (i = 0; i < relocs32.count; i++)
+			write_reloc(relocs32.offset[i], stdout);
+	}
+}
+
+/*
+ * As an aid to debugging problems with different linkers
+ * print summary information about the relocs.
+ * Since different linkers tend to emit the sections in
+ * different orders we use the section names in the output.
+ */
+static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
+				const char *symname)
+{
+	printf("%s\t%s\t%s\t%s\n",
+		sec_name(sec->shdr.sh_info),
+		rel_type(ELF_R_TYPE(rel->r_info)),
+		symname,
+		sec_name(sym_index(sym)));
+
+	return 0;
+}
+
+static void print_reloc_info(void)
+{
+	printf("reloc section\treloc type\tsymbol\tsymbol section\n");
+	walk_relocs(do_reloc_info);
+}
+
+#if ELF_BITS == 64
+# define process process_64
+#else
+# define process process_32
+#endif
+
+void process(FILE *fp, int use_real_mode, int as_text,
+	     int show_absolute_syms, int show_absolute_relocs,
+	     int show_reloc_info)
+{
+	regex_init(use_real_mode);
+	read_ehdr(fp);
+	read_shdrs(fp);
+	read_strtabs(fp);
+	read_symtabs(fp);
+	read_relocs(fp);
+
+	if (show_absolute_syms) {
+		print_absolute_symbols();
+		return;
+	}
+
+	if (show_absolute_relocs) {
+		print_absolute_relocs();
+		return;
+	}
+
+	if (show_reloc_info) {
+		print_reloc_info();
+		return;
+	}
+
+	emit_relocs(as_text, use_real_mode);
+}
diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h
new file mode 100644
index 000000000..4c49c8244
--- /dev/null
+++ b/arch/x86/tools/relocs.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef RELOCS_H
+#define RELOCS_H
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <inttypes.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>
+
+__attribute__((__format__(printf, 1, 2)))
+void die(char *fmt, ...) __attribute__((noreturn));
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+enum symtype {
+	S_ABS,
+	S_REL,
+	S_SEG,
+	S_LIN,
+	S_NSYMTYPES
+};
+
+void process_32(FILE *fp, int use_real_mode, int as_text,
+		int show_absolute_syms, int show_absolute_relocs,
+		int show_reloc_info);
+void process_64(FILE *fp, int use_real_mode, int as_text,
+		int show_absolute_syms, int show_absolute_relocs,
+		int show_reloc_info);
+#endif /* RELOCS_H */
diff --git a/arch/x86/tools/relocs_32.c b/arch/x86/tools/relocs_32.c
new file mode 100644
index 000000000..9442ff78b
--- /dev/null
+++ b/arch/x86/tools/relocs_32.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "relocs.h"
+
+#define ELF_BITS 32
+
+#define ELF_MACHINE		EM_386
+#define ELF_MACHINE_NAME	"i386"
+#define SHT_REL_TYPE		SHT_REL
+#define Elf_Rel			ElfW(Rel)
+
+#define ELF_CLASS		ELFCLASS32
+#define ELF_R_SYM(val)		ELF32_R_SYM(val)
+#define ELF_R_TYPE(val)		ELF32_R_TYPE(val)
+#define ELF_ST_TYPE(o)		ELF32_ST_TYPE(o)
+#define ELF_ST_BIND(o)		ELF32_ST_BIND(o)
+#define ELF_ST_VISIBILITY(o)	ELF32_ST_VISIBILITY(o)
+
+#include "relocs.c"
diff --git a/arch/x86/tools/relocs_64.c b/arch/x86/tools/relocs_64.c
new file mode 100644
index 000000000..9029cb619
--- /dev/null
+++ b/arch/x86/tools/relocs_64.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "relocs.h"
+
+#define ELF_BITS 64
+
+#define ELF_MACHINE             EM_X86_64
+#define ELF_MACHINE_NAME        "x86_64"
+#define SHT_REL_TYPE            SHT_RELA
+#define Elf_Rel                 Elf64_Rela
+
+#define ELF_CLASS               ELFCLASS64
+#define ELF_R_SYM(val)          ELF64_R_SYM(val)
+#define ELF_R_TYPE(val)         ELF64_R_TYPE(val)
+#define ELF_ST_TYPE(o)          ELF64_ST_TYPE(o)
+#define ELF_ST_BIND(o)          ELF64_ST_BIND(o)
+#define ELF_ST_VISIBILITY(o)    ELF64_ST_VISIBILITY(o)
+
+#include "relocs.c"
diff --git a/arch/x86/tools/relocs_common.c b/arch/x86/tools/relocs_common.c
new file mode 100644
index 000000000..6634352a2
--- /dev/null
+++ b/arch/x86/tools/relocs_common.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "relocs.h"
+
+void die(char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	exit(1);
+}
+
+static void usage(void)
+{
+	die("relocs [--abs-syms|--abs-relocs|--reloc-info|--text|--realmode]" \
+	    " vmlinux\n");
+}
+
+int main(int argc, char **argv)
+{
+	int show_absolute_syms, show_absolute_relocs, show_reloc_info;
+	int as_text, use_real_mode;
+	const char *fname;
+	FILE *fp;
+	int i;
+	unsigned char e_ident[EI_NIDENT];
+
+	show_absolute_syms = 0;
+	show_absolute_relocs = 0;
+	show_reloc_info = 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, "--reloc-info") == 0) {
+				show_reloc_info = 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();
+	}
+	fp = fopen(fname, "r");
+	if (!fp) {
+		die("Cannot open %s: %s\n", fname, strerror(errno));
+	}
+	if (fread(&e_ident, 1, EI_NIDENT, fp) != EI_NIDENT) {
+		die("Cannot read %s: %s", fname, strerror(errno));
+	}
+	rewind(fp);
+	if (e_ident[EI_CLASS] == ELFCLASS64)
+		process_64(fp, use_real_mode, as_text,
+			   show_absolute_syms, show_absolute_relocs,
+			   show_reloc_info);
+	else
+		process_32(fp, use_real_mode, as_text,
+			   show_absolute_syms, show_absolute_relocs,
+			   show_reloc_info);
+	fclose(fp);
+	return 0;
+}
diff --git a/arch/x86/tools/vdso2c.c b/arch/x86/tools/vdso2c.c
new file mode 100644
index 000000000..64a636b9f
--- /dev/null
+++ b/arch/x86/tools/vdso2c.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vdso2c - A vdso image preparation tool
+ * Copyright (c) 2014 Andy Lutomirski and others
+ *
+ * vdso2c requires stripped and unstripped input.  It would be trivial
+ * to fully strip the input in here, but, for reasons described below,
+ * we need to write a section table.  Doing this is more or less
+ * equivalent to dropping all non-allocatable sections, but it's
+ * easier to let objcopy handle that instead of doing it ourselves.
+ * If we ever need to do something fancier than what objcopy provides,
+ * it would be straightforward to add here.
+ *
+ * We're keep a section table for a few reasons:
+ *
+ * The Go runtime had a couple of bugs: it would read the section
+ * table to try to figure out how many dynamic symbols there were (it
+ * shouldn't have looked at the section table at all) and, if there
+ * were no SHT_SYNDYM section table entry, it would use an
+ * uninitialized value for the number of symbols.  An empty DYNSYM
+ * table would work, but I see no reason not to write a valid one (and
+ * keep full performance for old Go programs).  This hack is only
+ * needed on x86_64.
+ *
+ * The bug was introduced on 2012-08-31 by:
+ * https://code.google.com/p/go/source/detail?r=56ea40aac72b
+ * and was fixed on 2014-06-13 by:
+ * https://code.google.com/p/go/source/detail?r=fc1cd5e12595
+ *
+ * Binutils has issues debugging the vDSO: it reads the section table to
+ * find SHT_NOTE; it won't look at PT_NOTE for the in-memory vDSO, which
+ * would break build-id if we removed the section table.  Binutils
+ * also requires that shstrndx != 0.  See:
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=17064
+ *
+ * elfutils might not look for PT_NOTE if there is a section table at
+ * all.  I don't know whether this matters for any practical purpose.
+ *
+ * For simplicity, rather than hacking up a partial section table, we
+ * just write a mostly complete one.  We omit non-dynamic symbols,
+ * though, since they're rather large.
+ *
+ * Once binutils gets fixed, we might be able to drop this for all but
+ * the 64-bit vdso, since build-id only works in kernel RPMs, and
+ * systems that update to new enough kernel RPMs will likely update
+ * binutils in sync.  build-id has never worked for home-built kernel
+ * RPMs without manual symlinking, and I suspect that no one ever does
+ * that.
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <err.h>
+
+#include <sys/mman.h>
+#include <sys/types.h>
+
+#include <tools/le_byteshift.h>
+
+#include <linux/elf.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+
+const char *outfilename;
+
+struct vdso_sym {
+	const char *name;
+	bool export;
+};
+
+struct vdso_sym required_syms[] = {
+	{"__kernel_vsyscall",				true},
+	{"__kernel_sigreturn",				true},
+	{"__kernel_rt_sigreturn",			true},
+	{"int80_landing_pad",				true},
+	{"vdso32_rt_sigreturn_landing_pad",		true},
+	{"vdso32_sigreturn_landing_pad",		true},
+	{"__futex_list64_try_unlock_cs_start",		true},
+	{"__futex_list64_try_unlock_cs_end",		true},
+	{"__futex_list32_try_unlock_cs_start",		true},
+	{"__futex_list32_try_unlock_cs_end",		true},
+};
+
+__attribute__((format(printf, 1, 2))) __attribute__((noreturn))
+static void fail(const char *format, ...)
+{
+	va_list ap;
+	va_start(ap, format);
+	fprintf(stderr, "Error: ");
+	vfprintf(stderr, format, ap);
+	if (outfilename)
+		unlink(outfilename);
+	exit(1);
+	va_end(ap);
+}
+
+/*
+ * Evil macros for little-endian reads and writes
+ */
+#define GLE(x, bits, ifnot)						\
+	__builtin_choose_expr(						\
+		(sizeof(*(x)) == bits/8),				\
+		(__typeof__(*(x)))get_unaligned_le##bits(x), ifnot)
+
+extern void bad_get_le(void);
+#define LAST_GLE(x)							\
+	__builtin_choose_expr(sizeof(*(x)) == 1, *(x), bad_get_le())
+
+#define GET_LE(x)							\
+	GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_GLE(x))))
+
+#define PLE(x, val, bits, ifnot)					\
+	__builtin_choose_expr(						\
+		(sizeof(*(x)) == bits/8),				\
+		put_unaligned_le##bits((val), (x)), ifnot)
+
+extern void bad_put_le(void);
+#define LAST_PLE(x, val)						\
+	__builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), bad_put_le())
+
+#define PUT_LE(x, val)					\
+	PLE(x, val, 64, PLE(x, val, 32, PLE(x, val, 16, LAST_PLE(x, val))))
+
+
+#define NSYMS ARRAY_SIZE(required_syms)
+
+#define BITSFUNC3(name, bits, suffix) name##bits##suffix
+#define BITSFUNC2(name, bits, suffix) BITSFUNC3(name, bits, suffix)
+#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS, )
+
+#define INT_BITS BITSFUNC2(int, ELF_BITS, _t)
+
+#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
+#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
+#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
+
+#define ELF_BITS 64
+#include "vdso2c.h"
+#undef ELF_BITS
+
+#define ELF_BITS 32
+#include "vdso2c.h"
+#undef ELF_BITS
+
+static void go(void *raw_addr, size_t raw_len,
+	       void *stripped_addr, size_t stripped_len,
+	       FILE *outfile, const char *name)
+{
+	Elf64_Ehdr *hdr = (Elf64_Ehdr *)raw_addr;
+
+	if (hdr->e_ident[EI_CLASS] == ELFCLASS64) {
+		go64(raw_addr, raw_len, stripped_addr, stripped_len,
+		     outfile, name);
+	} else if (hdr->e_ident[EI_CLASS] == ELFCLASS32) {
+		go32(raw_addr, raw_len, stripped_addr, stripped_len,
+		     outfile, name);
+	} else {
+		fail("unknown ELF class\n");
+	}
+}
+
+static void map_input(const char *name, void **addr, size_t *len, int prot)
+{
+	off_t tmp_len;
+
+	int fd = open(name, O_RDONLY);
+	if (fd == -1)
+		err(1, "open(%s)", name);
+
+	tmp_len = lseek(fd, 0, SEEK_END);
+	if (tmp_len == (off_t)-1)
+		err(1, "lseek");
+	*len = (size_t)tmp_len;
+
+	*addr = mmap(NULL, tmp_len, prot, MAP_PRIVATE, fd, 0);
+	if (*addr == MAP_FAILED)
+		err(1, "mmap");
+
+	close(fd);
+}
+
+int main(int argc, char **argv)
+{
+	size_t raw_len, stripped_len;
+	void *raw_addr, *stripped_addr;
+	FILE *outfile;
+	char *name, *tmp;
+	int namelen;
+
+	if (argc != 4) {
+		printf("Usage: vdso2c RAW_INPUT STRIPPED_INPUT OUTPUT\n");
+		return 1;
+	}
+
+	/*
+	 * Figure out the struct name.  If we're writing to a .so file,
+	 * generate raw output instead.
+	 */
+	name = strdup(argv[3]);
+	namelen = strlen(name);
+	if (namelen >= 3 && !strcmp(name + namelen - 3, ".so")) {
+		name = NULL;
+	} else {
+		tmp = strrchr(name, '/');
+		if (tmp)
+			name = tmp + 1;
+		tmp = strchr(name, '.');
+		if (tmp)
+			*tmp = '\0';
+		for (tmp = name; *tmp; tmp++)
+			if (*tmp == '-')
+				*tmp = '_';
+	}
+
+	map_input(argv[1], &raw_addr, &raw_len, PROT_READ);
+	map_input(argv[2], &stripped_addr, &stripped_len, PROT_READ);
+
+	outfilename = argv[3];
+	outfile = fopen(outfilename, "w");
+	if (!outfile)
+		err(1, "fopen(%s)", outfilename);
+
+	go(raw_addr, raw_len, stripped_addr, stripped_len, outfile, name);
+
+	munmap(raw_addr, raw_len);
+	munmap(stripped_addr, stripped_len);
+	fclose(outfile);
+
+	return 0;
+}
diff --git a/arch/x86/tools/vdso2c.h b/arch/x86/tools/vdso2c.h
new file mode 100644
index 000000000..78ed1c1f2
--- /dev/null
+++ b/arch/x86/tools/vdso2c.h
@@ -0,0 +1,208 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This file is included twice from vdso2c.c.  It generates code for 32-bit
+ * and 64-bit vDSOs.  We need both for 64-bit builds, since 32-bit vDSOs
+ * are built for 32-bit userspace.
+ */
+
+static void BITSFUNC(copy)(FILE *outfile, const unsigned char *data, size_t len)
+{
+	size_t i;
+
+	for (i = 0; i < len; i++) {
+		if (i % 10 == 0)
+			fprintf(outfile, "\n\t");
+		fprintf(outfile, "0x%02X, ", (int)(data)[i]);
+	}
+}
+
+
+/*
+ * Extract a section from the input data into a standalone blob.  Used to
+ * capture kernel-only data that needs to persist indefinitely, e.g. the
+ * exception fixup tables, but only in the kernel, i.e. the section can
+ * be stripped from the final vDSO image.
+ */
+static void BITSFUNC(extract)(const unsigned char *data, size_t data_len,
+			      FILE *outfile, ELF(Shdr) *sec, const char *name)
+{
+	unsigned long offset;
+	size_t len;
+
+	offset = (unsigned long)GET_LE(&sec->sh_offset);
+	len = (size_t)GET_LE(&sec->sh_size);
+
+	if (offset + len > data_len)
+		fail("section to extract overruns input data");
+
+	fprintf(outfile, "static const unsigned char %s[%zu] = {", name, len);
+	BITSFUNC(copy)(outfile, data + offset, len);
+	fprintf(outfile, "\n};\n\n");
+}
+
+static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
+			 void *stripped_addr, size_t stripped_len,
+			 FILE *outfile, const char *image_name)
+{
+	int found_load = 0;
+	unsigned long load_size = -1;  /* Work around bogus warning */
+	unsigned long mapping_size;
+	ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
+	unsigned long i, syms_nr;
+	ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
+		*alt_sec = NULL, *extable_sec = NULL;
+	ELF(Dyn) *dyn = 0, *dyn_end = 0;
+	const char *secstrings;
+	INT_BITS syms[NSYMS] = {};
+
+	ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_LE(&hdr->e_phoff));
+
+	if (GET_LE(&hdr->e_type) != ET_DYN)
+		fail("input is not a shared object\n");
+
+	/* Walk the segment table. */
+	for (i = 0; i < GET_LE(&hdr->e_phnum); i++) {
+		if (GET_LE(&pt[i].p_type) == PT_LOAD) {
+			if (found_load)
+				fail("multiple PT_LOAD segs\n");
+
+			if (GET_LE(&pt[i].p_offset) != 0 ||
+			    GET_LE(&pt[i].p_vaddr) != 0)
+				fail("PT_LOAD in wrong place\n");
+
+			if (GET_LE(&pt[i].p_memsz) != GET_LE(&pt[i].p_filesz))
+				fail("cannot handle memsz != filesz\n");
+
+			load_size = GET_LE(&pt[i].p_memsz);
+			found_load = 1;
+		} else if (GET_LE(&pt[i].p_type) == PT_DYNAMIC) {
+			dyn = raw_addr + GET_LE(&pt[i].p_offset);
+			dyn_end = raw_addr + GET_LE(&pt[i].p_offset) +
+				GET_LE(&pt[i].p_memsz);
+		}
+	}
+	if (!found_load)
+		fail("no PT_LOAD seg\n");
+
+	if (stripped_len < load_size)
+		fail("stripped input is too short\n");
+
+	if (!dyn)
+		fail("input has no PT_DYNAMIC section -- your toolchain is buggy\n");
+
+	/* Walk the dynamic table */
+	for (i = 0; dyn + i < dyn_end &&
+		     GET_LE(&dyn[i].d_tag) != DT_NULL; i++) {
+		typeof(dyn[i].d_tag) tag = GET_LE(&dyn[i].d_tag);
+		if (tag == DT_REL || tag == DT_RELSZ || tag == DT_RELA ||
+		    tag == DT_RELENT || tag == DT_TEXTREL)
+			fail("vdso image contains dynamic relocations\n");
+	}
+
+	/* Walk the section table */
+	secstrings_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
+		GET_LE(&hdr->e_shentsize)*GET_LE(&hdr->e_shstrndx);
+	secstrings = raw_addr + GET_LE(&secstrings_hdr->sh_offset);
+	for (i = 0; i < GET_LE(&hdr->e_shnum); i++) {
+		ELF(Shdr) *sh = raw_addr + GET_LE(&hdr->e_shoff) +
+			GET_LE(&hdr->e_shentsize) * i;
+		if (GET_LE(&sh->sh_type) == SHT_SYMTAB)
+			symtab_hdr = sh;
+
+		if (!strcmp(secstrings + GET_LE(&sh->sh_name),
+			    ".altinstructions"))
+			alt_sec = sh;
+		if (!strcmp(secstrings + GET_LE(&sh->sh_name), "__ex_table"))
+			extable_sec = sh;
+	}
+
+	if (!symtab_hdr)
+		fail("no symbol table\n");
+
+	strtab_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
+		GET_LE(&hdr->e_shentsize) * GET_LE(&symtab_hdr->sh_link);
+
+	syms_nr = GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
+	/* Walk the symbol table */
+	for (i = 0; i < syms_nr; i++) {
+		unsigned int k;
+		ELF(Sym) *sym = raw_addr + GET_LE(&symtab_hdr->sh_offset) +
+			GET_LE(&symtab_hdr->sh_entsize) * i;
+		const char *sym_name = raw_addr +
+				       GET_LE(&strtab_hdr->sh_offset) +
+				       GET_LE(&sym->st_name);
+
+		for (k = 0; k < NSYMS; k++) {
+			if (!strcmp(sym_name, required_syms[k].name)) {
+				if (syms[k]) {
+					fail("duplicate symbol %s\n",
+					     required_syms[k].name);
+				}
+
+				/*
+				 * Careful: we use negative addresses, but
+				 * st_value is unsigned, so we rely
+				 * on syms[k] being a signed type of the
+				 * correct width.
+				 */
+				syms[k] = GET_LE(&sym->st_value);
+			}
+		}
+	}
+
+	if (!image_name) {
+		fwrite(stripped_addr, stripped_len, 1, outfile);
+		return;
+	}
+
+	mapping_size = (stripped_len + 4095) / 4096 * 4096;
+
+	fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n");
+	fprintf(outfile, "#include <linux/linkage.h>\n");
+	fprintf(outfile, "#include <linux/init.h>\n");
+	fprintf(outfile, "#include <asm/page_types.h>\n");
+	fprintf(outfile, "#include <asm/vdso.h>\n");
+	fprintf(outfile, "\n");
+	fprintf(outfile,
+		"static unsigned char raw_data[%lu] __ro_after_init __aligned(PAGE_SIZE) = {",
+		mapping_size);
+	for (i = 0; i < stripped_len; i++) {
+		if (i % 10 == 0)
+			fprintf(outfile, "\n\t");
+		fprintf(outfile, "0x%02X, ",
+			(int)((unsigned char *)stripped_addr)[i]);
+	}
+	fprintf(outfile, "\n};\n\n");
+	if (extable_sec)
+		BITSFUNC(extract)(raw_addr, raw_len, outfile,
+				  extable_sec, "extable");
+
+	fprintf(outfile, "const struct vdso_image %s = {\n", image_name);
+	fprintf(outfile, "\t.data = raw_data,\n");
+	fprintf(outfile, "\t.size = %lu,\n", mapping_size);
+	if (alt_sec) {
+		fprintf(outfile, "\t.alt = %lu,\n",
+			(unsigned long)GET_LE(&alt_sec->sh_offset));
+		fprintf(outfile, "\t.alt_len = %lu,\n",
+			(unsigned long)GET_LE(&alt_sec->sh_size));
+	}
+	if (extable_sec) {
+		fprintf(outfile, "\t.extable_base = %lu,\n",
+			(unsigned long)GET_LE(&extable_sec->sh_offset));
+		fprintf(outfile, "\t.extable_len = %lu,\n",
+			(unsigned long)GET_LE(&extable_sec->sh_size));
+		fprintf(outfile, "\t.extable = extable,\n");
+	}
+
+	for (i = 0; i < NSYMS; i++) {
+		if (required_syms[i].export && syms[i])
+			fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
+				required_syms[i].name, (int64_t)syms[i]);
+	}
+	fprintf(outfile, "};\n\n");
+	fprintf(outfile, "static __init int init_%s(void) {\n", image_name);
+	fprintf(outfile, "\treturn init_vdso_image(&%s);\n", image_name);
+	fprintf(outfile, "};\n");
+	fprintf(outfile, "subsys_initcall(init_%s);\n", image_name);
+
+}