scripts/faddr2line - linux - Git at Google

 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 #
 # Translate stack dump function offsets.
 #
 # addr2line doesn't work with KASLR addresses.  This works similarly to
 # addr2line, but instead takes the 'func+0x123' format as input:
 #
 #   $ ./scripts/faddr2line ~/k/vmlinux meminfo_proc_show+0x5/0x568
 #   meminfo_proc_show+0x5/0x568:
 #   meminfo_proc_show at fs/proc/meminfo.c:27
 #
 # If the address is part of an inlined function, the full inline call chain is
 # printed:
 #
 #   $ ./scripts/faddr2line ~/k/vmlinux native_write_msr+0x6/0x27
 #   native_write_msr+0x6/0x27:
 #   arch_static_branch at arch/x86/include/asm/msr.h:121
 #    (inlined by) static_key_false at include/linux/jump_label.h:125
 #    (inlined by) native_write_msr at arch/x86/include/asm/msr.h:125
 #
 # The function size after the '/' in the input is optional, but recommended.
 # It's used to help disambiguate any duplicate symbol names, which can occur
 # rarely.  If the size is omitted for a duplicate symbol then it's possible for
 # multiple code sites to be printed:
 #
 #   $ ./scripts/faddr2line ~/k/vmlinux raw_ioctl+0x5
 #   raw_ioctl+0x5/0x20:
 #   raw_ioctl at drivers/char/raw.c:122
 #
 #   raw_ioctl+0x5/0xb1:
 #   raw_ioctl at net/ipv4/raw.c:876
 #
 # Multiple addresses can be specified on a single command line:
 #
 #   $ ./scripts/faddr2line ~/k/vmlinux type_show+0x10/45 free_reserved_area+0x90
 #   type_show+0x10/0x2d:
 #   type_show at drivers/video/backlight/backlight.c:213
 #
 #   free_reserved_area+0x90/0x123:
 #   free_reserved_area at mm/page_alloc.c:6429 (discriminator 2)


 set -o errexit
 set -o nounset

 usage() {
 	echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
 	exit 1
 }

 warn() {
 	echo "$1" >&2
 }

 die() {
 	echo "ERROR: $1" >&2
 	exit 1
 }

 UTIL_SUFFIX=""
 if [[ "${LLVM:-}" == "" ]]; then
 	UTIL_PREFIX=${CROSS_COMPILE:-}
 else
 	UTIL_PREFIX=llvm-

 	if [[ "${LLVM}" == *"/" ]]; then
 		UTIL_PREFIX=${LLVM}${UTIL_PREFIX}
 	elif [[ "${LLVM}" == "-"* ]]; then
 		UTIL_SUFFIX=${LLVM}
 	fi
 fi

 READELF="${UTIL_PREFIX}readelf${UTIL_SUFFIX}"
 ADDR2LINE="${UTIL_PREFIX}addr2line${UTIL_SUFFIX}"
 AWK="awk"
 GREP="grep"

 command -v ${AWK} >/dev/null 2>&1 || die "${AWK} isn't installed"
 command -v ${READELF} >/dev/null 2>&1 || die "${READELF} isn't installed"
 command -v ${ADDR2LINE} >/dev/null 2>&1 || die "${ADDR2LINE} isn't installed"

 # Try to figure out the source directory prefix so we can remove it from the
 # addr2line output.  HACK ALERT: This assumes that start_kernel() is in
 # init/main.c!  This only works for vmlinux.  Otherwise it falls back to
 # printing the absolute path.
 find_dir_prefix() {
 	local start_kernel_addr=$(echo "${ELF_SYMS}" | sed 's/\[.*\]//' |
 		${AWK} '$8 == "start_kernel" {printf "0x%s", $2}')
 	[[ -z $start_kernel_addr ]] && return

 	run_addr2line ${start_kernel_addr} ""
 	[[ -z $ADDR2LINE_OUT ]] && return

 	local file_line=${ADDR2LINE_OUT#* at }
 	if [[ -z $file_line ]] || [[ $file_line = $ADDR2LINE_OUT ]]; then
 		return
 	fi
 	local prefix=${file_line%init/main.c:*}
 	if [[ -z $prefix ]] || [[ $prefix = $file_line ]]; then
 		return
 	fi

 	DIR_PREFIX=$prefix
 	return 0
 }

 run_readelf() {
 	local objfile=$1
 	local out=$(${READELF} --file-header --section-headers --symbols --wide $objfile)

 	# This assumes that readelf first prints the file header, then the section headers, then the symbols.
 	# Note: It seems that GNU readelf does not prefix section headers with the "There are X section headers"
 	# line when multiple options are given, so let's also match with the "Section Headers:" line.
 	ELF_FILEHEADER=$(echo "${out}" | sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/q;p')
 	ELF_SECHEADERS=$(echo "${out}" | sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/,$p' | sed -n '/Symbol table .* contains [0-9]* entries:/q;p')
 	ELF_SYMS=$(echo "${out}" | sed -n '/Symbol table .* contains [0-9]* entries:/,$p')
 }

 check_vmlinux() {
 	# vmlinux uses absolute addresses in the section table rather than
 	# section offsets.
 	IS_VMLINUX=0
 	local file_type=$(echo "${ELF_FILEHEADER}" |
 		${AWK} '$1 == "Type:" { print $2; exit }')
 	if [[ $file_type = "EXEC" ]] || [[ $file_type == "DYN" ]]; then
 		IS_VMLINUX=1
 	fi
 }

 init_addr2line() {
 	local objfile=$1

 	check_vmlinux

 	ADDR2LINE_ARGS="--functions --pretty-print --inlines --addresses --exe=$objfile"
 	if [[ $IS_VMLINUX = 1 ]]; then
 		# If the executable file is vmlinux, we don't pass section names to
 		# addr2line, so we can launch it now as a single long-running process.
 		coproc ADDR2LINE_PROC (${ADDR2LINE} ${ADDR2LINE_ARGS})
 	fi
 }

 run_addr2line() {
 	local addr=$1
 	local sec_name=$2

 	if [[ $IS_VMLINUX = 1 ]]; then
 		# We send to the addr2line process: (1) the address, then (2) a sentinel
 		# value, i.e., something that can't be interpreted as a valid address
 		# (i.e., ","). This causes addr2line to write out: (1) the answer for
 		# our address, then (2) either "?? ??:0" or "0x0...0: ..." (if
 		# using binutils' addr2line), or "," (if using LLVM's addr2line).
 		echo ${addr} >& "${ADDR2LINE_PROC[1]}"
 		echo "," >& "${ADDR2LINE_PROC[1]}"
 		local first_line
 		read -r first_line <& "${ADDR2LINE_PROC[0]}"
 		ADDR2LINE_OUT=$(echo "${first_line}" | sed 's/^0x[0-9a-fA-F]*: //')
 		while read -r line <& "${ADDR2LINE_PROC[0]}"; do
 			if [[ "$line" == "?? ??:0" ]] || [[ "$line" == "," ]] || [[ $(echo "$line" | ${GREP} "^0x00*: ") ]]; then
 				break
 			fi
 			ADDR2LINE_OUT+=$'\n'$(echo "$line" | sed 's/^0x[0-9a-fA-F]*: //')
 		done
 	else
 		# Run addr2line as a single invocation.
 		local sec_arg
 		[[ -z $sec_name ]] && sec_arg="" || sec_arg="--section=${sec_name}"
 		ADDR2LINE_OUT=$(${ADDR2LINE} ${ADDR2LINE_ARGS} ${sec_arg} ${addr} | sed 's/^0x[0-9a-fA-F]*: //')
 	fi
 }

 __faddr2line() {
 	local objfile=$1
 	local func_addr=$2
 	local dir_prefix=$3
 	local print_warnings=$4

 	local sym_name=${func_addr%+*}
 	local func_offset=${func_addr#*+}
 	func_offset=${func_offset%/*}
 	local user_size=
 	[[ $func_addr =~ "/" ]] && user_size=${func_addr#*/}

 	if [[ -z $sym_name ]] || [[ -z $func_offset ]] || [[ $sym_name = $func_addr ]]; then
 		warn "bad func+offset $func_addr"
 		DONE=1
 		return
 	fi

 	# Go through each of the object's symbols which match the func name.
 	# In rare cases there might be duplicates, in which case we print all
 	# matches.
 	while read line; do
 		local fields=($line)
 		local sym_addr=0x${fields[1]}
 		local sym_elf_size=${fields[2]}
 		local sym_sec=${fields[6]}
 		local sec_size
 		local sec_name

 		# Get the section size:
 		sec_size=$(echo "${ELF_SECHEADERS}" | sed 's/\[ /\[/' |
 			${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')

 		if [[ -z $sec_size ]]; then
 			warn "bad section size: section: $sym_sec"
 			DONE=1
 			return
 		fi

 		# Get the section name:
 		sec_name=$(echo "${ELF_SECHEADERS}" | sed 's/\[ /\[/' |
 			${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print $2; exit }')

 		if [[ -z $sec_name ]]; then
 			warn "bad section name: section: $sym_sec"
 			DONE=1
 			return
 		fi

 		# Calculate the symbol size.
 		#
 		# Unfortunately we can't use the ELF size, because kallsyms
 		# also includes the padding bytes in its size calculation.  For
 		# kallsyms, the size calculation is the distance between the
 		# symbol and the next symbol in a sorted list.
 		local sym_size
 		local cur_sym_addr
 		local found=0
 		while read line; do
 			local fields=($line)
 			cur_sym_addr=0x${fields[1]}
 			local cur_sym_elf_size=${fields[2]}
 			local cur_sym_name=${fields[7]:-}

 			# is_mapping_symbol(cur_sym_name)
 			if [[ ${cur_sym_name} =~ ^(\.L|L0|\$) ]]; then
 				continue
 			fi

 			if [[ $cur_sym_addr = $sym_addr ]] &&
 			   [[ $cur_sym_elf_size = $sym_elf_size ]] &&
 			   [[ $cur_sym_name = $sym_name ]]; then
 				found=1
 				continue
 			fi

 			if [[ $found = 1 ]]; then
 				sym_size=$(($cur_sym_addr - $sym_addr))
 				[[ $sym_size -lt $sym_elf_size ]] && continue;
 				found=2
 				break
 			fi
 		done < <(echo "${ELF_SYMS}" | sed 's/\[.*\]//' | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)

 		if [[ $found = 0 ]]; then
 			warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size"
 			DONE=1
 			return
 		fi

 		# If nothing was found after the symbol, assume it's the last
 		# symbol in the section.
 		[[ $found = 1 ]] && sym_size=$(($sec_size - $sym_addr))

 		if [[ -z $sym_size ]] || [[ $sym_size -le 0 ]]; then
 			warn "bad symbol size: sym_addr: $sym_addr cur_sym_addr: $cur_sym_addr"
 			DONE=1
 			return
 		fi

 		sym_size=0x$(printf %x $sym_size)

 		# Calculate the address from user-supplied offset:
 		local addr=$(($sym_addr + $func_offset))
 		if [[ -z $addr ]] || [[ $addr = 0 ]]; then
 			warn "bad address: $sym_addr + $func_offset"
 			DONE=1
 			return
 		fi
 		addr=0x$(printf %x $addr)

 		# If the user provided a size, make sure it matches the symbol's size:
 		if [[ -n $user_size ]] && [[ $user_size -ne $sym_size ]]; then
 			[[ $print_warnings = 1 ]] &&
 				echo "skipping $sym_name address at $addr due to size mismatch ($user_size != $sym_size)"
 			continue;
 		fi

 		# Make sure the provided offset is within the symbol's range:
 		if [[ $func_offset -gt $sym_size ]]; then
 			[[ $print_warnings = 1 ]] &&
 				echo "skipping $sym_name address at $addr due to size mismatch ($func_offset > $sym_size)"
 			continue
 		fi

 		# In case of duplicates or multiple addresses specified on the
 		# cmdline, separate multiple entries with a blank line:
 		[[ $FIRST = 0 ]] && echo
 		FIRST=0

 		echo "$sym_name+$func_offset/$sym_size:"

 		# Pass section address to addr2line and strip absolute paths
 		# from the output:
 		run_addr2line $addr $sec_name
 		local output=$(echo "${ADDR2LINE_OUT}" | sed "s; $dir_prefix\(\./\)*; ;")
 		[[ -z $output ]] && continue

 		# Default output (non --list):
 		if [[ $LIST = 0 ]]; then
 			echo "$output" | while read -r line
 			do
 				echo $line
 			done
 			DONE=1;
 			continue
 		fi

 		# For --list, show each line with its corresponding source code:
 		echo "$output" | while read -r line
 		do
 			echo
 			echo $line
 			n=$(echo $line | sed 's/.*:\([0-9]\+\).*/\1/g')
 			n1=$[$n-5]
 			n2=$[$n+5]
 			f=$(echo $line | sed 's/.*at \(.\+\):.*/\1/g')
 			${AWK} 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
 		done

 		DONE=1

 	done < <(echo "${ELF_SYMS}" | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$8 == fn')
 }

 [[ $# -lt 2 ]] && usage

 objfile=$1

 LIST=0
 [[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1

 [[ ! -f $objfile ]] && die "can't find objfile $objfile"
 shift

 run_readelf $objfile

 echo "${ELF_SECHEADERS}" | ${GREP} -q '\.debug_info' || die "CONFIG_DEBUG_INFO not enabled"

 init_addr2line $objfile

 DIR_PREFIX=supercalifragilisticexpialidocious
 find_dir_prefix

 FIRST=1
 while [[ $# -gt 0 ]]; do
 	func_addr=$1
 	shift

 	# print any matches found
 	DONE=0
 	__faddr2line $objfile $func_addr $DIR_PREFIX 0

 	# if no match was found, print warnings
 	if [[ $DONE = 0 ]]; then
 		__faddr2line $objfile $func_addr $DIR_PREFIX 1
 		warn "no match for $func_addr"
 	fi
 done
	#!/bin/bash
	# SPDX-License-Identifier: GPL-2.0
	#
	# Translate stack dump function offsets.
	#
	# addr2line doesn't work with KASLR addresses. This works similarly to
	# addr2line, but instead takes the 'func+0x123' format as input:
	#
	# $ ./scripts/faddr2line ~/k/vmlinux meminfo_proc_show+0x5/0x568
	# meminfo_proc_show+0x5/0x568:
	# meminfo_proc_show at fs/proc/meminfo.c:27
	#
	# If the address is part of an inlined function, the full inline call chain is
	# printed:
	#
	# $ ./scripts/faddr2line ~/k/vmlinux native_write_msr+0x6/0x27
	# native_write_msr+0x6/0x27:
	# arch_static_branch at arch/x86/include/asm/msr.h:121
	# (inlined by) static_key_false at include/linux/jump_label.h:125
	# (inlined by) native_write_msr at arch/x86/include/asm/msr.h:125
	#
	# The function size after the '/' in the input is optional, but recommended.
	# It's used to help disambiguate any duplicate symbol names, which can occur
	# rarely. If the size is omitted for a duplicate symbol then it's possible for
	# multiple code sites to be printed:
	#
	# $ ./scripts/faddr2line ~/k/vmlinux raw_ioctl+0x5
	# raw_ioctl+0x5/0x20:
	# raw_ioctl at drivers/char/raw.c:122
	#
	# raw_ioctl+0x5/0xb1:
	# raw_ioctl at net/ipv4/raw.c:876
	#
	# Multiple addresses can be specified on a single command line:
	#
	# $ ./scripts/faddr2line ~/k/vmlinux type_show+0x10/45 free_reserved_area+0x90
	# type_show+0x10/0x2d:
	# type_show at drivers/video/backlight/backlight.c:213
	#
	# free_reserved_area+0x90/0x123:
	# free_reserved_area at mm/page_alloc.c:6429 (discriminator 2)


	set -o errexit
	set -o nounset

	usage() {
	echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
	exit 1
	}

	warn() {
	echo "$1" >&2
	}

	die() {
	echo "ERROR: $1" >&2
	exit 1
	}

	UTIL_SUFFIX=""
	if [[ "${LLVM:-}" == "" ]]; then
	UTIL_PREFIX=${CROSS_COMPILE:-}
	else
	UTIL_PREFIX=llvm-

	if [[ "${LLVM}" == *"/" ]]; then
	UTIL_PREFIX=${LLVM}${UTIL_PREFIX}
	elif [[ "${LLVM}" == "-"* ]]; then
	UTIL_SUFFIX=${LLVM}
	fi
	fi

	READELF="${UTIL_PREFIX}readelf${UTIL_SUFFIX}"
	ADDR2LINE="${UTIL_PREFIX}addr2line${UTIL_SUFFIX}"
	AWK="awk"
	GREP="grep"

	command -v ${AWK} >/dev/null 2>&1 \|\| die "${AWK} isn't installed"
	command -v ${READELF} >/dev/null 2>&1 \|\| die "${READELF} isn't installed"
	command -v ${ADDR2LINE} >/dev/null 2>&1 \|\| die "${ADDR2LINE} isn't installed"

	# Try to figure out the source directory prefix so we can remove it from the
	# addr2line output. HACK ALERT: This assumes that start_kernel() is in
	# init/main.c! This only works for vmlinux. Otherwise it falls back to
	# printing the absolute path.
	find_dir_prefix() {
	local start_kernel_addr=$(echo "${ELF_SYMS}" \| sed 's/\[.*\]//' \|
	${AWK} '$8 == "start_kernel" {printf "0x%s", $2}')
	[[ -z $start_kernel_addr ]] && return

	run_addr2line ${start_kernel_addr} ""
	[[ -z $ADDR2LINE_OUT ]] && return

	local file_line=${ADDR2LINE_OUT#* at }
	if [[ -z $file_line ]] \|\| [[ $file_line = $ADDR2LINE_OUT ]]; then
	return
	fi
	local prefix=${file_line%init/main.c:*}
	if [[ -z $prefix ]] \|\| [[ $prefix = $file_line ]]; then
	return
	fi

	DIR_PREFIX=$prefix
	return 0
	}

	run_readelf() {
	local objfile=$1
	local out=$(${READELF} --file-header --section-headers --symbols --wide $objfile)

	# This assumes that readelf first prints the file header, then the section headers, then the symbols.
	# Note: It seems that GNU readelf does not prefix section headers with the "There are X section headers"
	# line when multiple options are given, so let's also match with the "Section Headers:" line.
	ELF_FILEHEADER=$(echo "${out}" \| sed -n '/There are [0-9]* section headers, starting at offset\\|Section Headers:/q;p')
	ELF_SECHEADERS=$(echo "${out}" \| sed -n '/There are [0-9]* section headers, starting at offset\\|Section Headers:/,$p' \| sed -n '/Symbol table .* contains [0-9]* entries:/q;p')
	ELF_SYMS=$(echo "${out}" \| sed -n '/Symbol table .* contains [0-9]* entries:/,$p')
	}

	check_vmlinux() {
	# vmlinux uses absolute addresses in the section table rather than
	# section offsets.
	IS_VMLINUX=0
	local file_type=$(echo "${ELF_FILEHEADER}" \|
	${AWK} '$1 == "Type:" { print $2; exit }')
	if [[ $file_type = "EXEC" ]] \|\| [[ $file_type == "DYN" ]]; then
	IS_VMLINUX=1
	fi
	}

	init_addr2line() {
	local objfile=$1

	check_vmlinux

	ADDR2LINE_ARGS="--functions --pretty-print --inlines --addresses --exe=$objfile"
	if [[ $IS_VMLINUX = 1 ]]; then
	# If the executable file is vmlinux, we don't pass section names to
	# addr2line, so we can launch it now as a single long-running process.
	coproc ADDR2LINE_PROC (${ADDR2LINE} ${ADDR2LINE_ARGS})
	fi
	}

	run_addr2line() {
	local addr=$1
	local sec_name=$2

	if [[ $IS_VMLINUX = 1 ]]; then
	# We send to the addr2line process: (1) the address, then (2) a sentinel
	# value, i.e., something that can't be interpreted as a valid address
	# (i.e., ","). This causes addr2line to write out: (1) the answer for
	# our address, then (2) either "?? ??:0" or "0x0...0: ..." (if
	# using binutils' addr2line), or "," (if using LLVM's addr2line).
	echo ${addr} >& "${ADDR2LINE_PROC[1]}"
	echo "," >& "${ADDR2LINE_PROC[1]}"
	local first_line
	read -r first_line <& "${ADDR2LINE_PROC[0]}"
	ADDR2LINE_OUT=$(echo "${first_line}" \| sed 's/^0x[0-9a-fA-F]*: //')
	while read -r line <& "${ADDR2LINE_PROC[0]}"; do
	if [[ "$line" == "?? ??:0" ]] \|\| [[ "$line" == "," ]] \|\| [[ $(echo "$line" \| ${GREP} "^0x00*: ") ]]; then
	break
	fi
	ADDR2LINE_OUT+=$'\n'$(echo "$line" \| sed 's/^0x[0-9a-fA-F]*: //')
	done
	else
	# Run addr2line as a single invocation.
	local sec_arg
	[[ -z $sec_name ]] && sec_arg="" \|\| sec_arg="--section=${sec_name}"
	ADDR2LINE_OUT=$(${ADDR2LINE} ${ADDR2LINE_ARGS} ${sec_arg} ${addr} \| sed 's/^0x[0-9a-fA-F]*: //')
	fi
	}

	__faddr2line() {
	local objfile=$1
	local func_addr=$2
	local dir_prefix=$3
	local print_warnings=$4

	local sym_name=${func_addr%+*}
	local func_offset=${func_addr#*+}
	func_offset=${func_offset%/*}
	local user_size=
	[[ $func_addr =~ "/" ]] && user_size=${func_addr#*/}

	if [[ -z $sym_name ]] \|\| [[ -z $func_offset ]] \|\| [[ $sym_name = $func_addr ]]; then
	warn "bad func+offset $func_addr"
	DONE=1
	return
	fi

	# Go through each of the object's symbols which match the func name.
	# In rare cases there might be duplicates, in which case we print all
	# matches.
	while read line; do
	local fields=($line)
	local sym_addr=0x${fields[1]}
	local sym_elf_size=${fields[2]}
	local sym_sec=${fields[6]}
	local sec_size
	local sec_name

	# Get the section size:
	sec_size=$(echo "${ELF_SECHEADERS}" \| sed 's/\[ /\[/' \|
	${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')

	if [[ -z $sec_size ]]; then
	warn "bad section size: section: $sym_sec"
	DONE=1
	return
	fi

	# Get the section name:
	sec_name=$(echo "${ELF_SECHEADERS}" \| sed 's/\[ /\[/' \|
	${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print $2; exit }')

	if [[ -z $sec_name ]]; then
	warn "bad section name: section: $sym_sec"
	DONE=1
	return
	fi

	# Calculate the symbol size.
	#
	# Unfortunately we can't use the ELF size, because kallsyms
	# also includes the padding bytes in its size calculation. For
	# kallsyms, the size calculation is the distance between the
	# symbol and the next symbol in a sorted list.
	local sym_size
	local cur_sym_addr
	local found=0
	while read line; do
	local fields=($line)
	cur_sym_addr=0x${fields[1]}
	local cur_sym_elf_size=${fields[2]}
	local cur_sym_name=${fields[7]:-}

	# is_mapping_symbol(cur_sym_name)
	if [[ ${cur_sym_name} =~ ^(\.L\|L0\|\$) ]]; then
	continue
	fi

	if [[ $cur_sym_addr = $sym_addr ]] &&
	[[ $cur_sym_elf_size = $sym_elf_size ]] &&
	[[ $cur_sym_name = $sym_name ]]; then
	found=1
	continue
	fi

	if [[ $found = 1 ]]; then
	sym_size=$(($cur_sym_addr - $sym_addr))
	[[ $sym_size -lt $sym_elf_size ]] && continue;
	found=2
	break
	fi
	done < <(echo "${ELF_SYMS}" \| sed 's/\[.*\]//' \| ${AWK} -v sec=$sym_sec '$7 == sec' \| sort --key=2)

	if [[ $found = 0 ]]; then
	warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size"
	DONE=1
	return
	fi

	# If nothing was found after the symbol, assume it's the last
	# symbol in the section.
	[[ $found = 1 ]] && sym_size=$(($sec_size - $sym_addr))

	if [[ -z $sym_size ]] \|\| [[ $sym_size -le 0 ]]; then
	warn "bad symbol size: sym_addr: $sym_addr cur_sym_addr: $cur_sym_addr"
	DONE=1
	return
	fi

	sym_size=0x$(printf %x $sym_size)

	# Calculate the address from user-supplied offset:
	local addr=$(($sym_addr + $func_offset))
	if [[ -z $addr ]] \|\| [[ $addr = 0 ]]; then
	warn "bad address: $sym_addr + $func_offset"
	DONE=1
	return
	fi
	addr=0x$(printf %x $addr)

	# If the user provided a size, make sure it matches the symbol's size:
	if [[ -n $user_size ]] && [[ $user_size -ne $sym_size ]]; then
	[[ $print_warnings = 1 ]] &&
	echo "skipping $sym_name address at $addr due to size mismatch ($user_size != $sym_size)"
	continue;
	fi

	# Make sure the provided offset is within the symbol's range:
	if [[ $func_offset -gt $sym_size ]]; then
	[[ $print_warnings = 1 ]] &&
	echo "skipping $sym_name address at $addr due to size mismatch ($func_offset > $sym_size)"
	continue
	fi

	# In case of duplicates or multiple addresses specified on the
	# cmdline, separate multiple entries with a blank line:
	[[ $FIRST = 0 ]] && echo
	FIRST=0

	echo "$sym_name+$func_offset/$sym_size:"

	# Pass section address to addr2line and strip absolute paths
	# from the output:
	run_addr2line $addr $sec_name
	local output=$(echo "${ADDR2LINE_OUT}" \| sed "s; $dir_prefix\(\./\)*; ;")
	[[ -z $output ]] && continue

	# Default output (non --list):
	if [[ $LIST = 0 ]]; then
	echo "$output" \| while read -r line
	do
	echo $line
	done
	DONE=1;
	continue
	fi

	# For --list, show each line with its corresponding source code:
	echo "$output" \| while read -r line
	do
	echo
	echo $line
	n=$(echo $line \| sed 's/.:\([0-9]\+\)./\1/g')
	n1=$[$n-5]
	n2=$[$n+5]
	f=$(echo $line \| sed 's/.at \(.\+\):./\1/g')
	${AWK} 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
	done

	DONE=1

	done < <(echo "${ELF_SYMS}" \| sed 's/\[.*\]//' \| ${AWK} -v fn=$sym_name '$8 == fn')
	}

	[[ $# -lt 2 ]] && usage

	objfile=$1

	LIST=0
	[[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1

	[[ ! -f $objfile ]] && die "can't find objfile $objfile"
	shift

	run_readelf $objfile

	echo "${ELF_SECHEADERS}" \| ${GREP} -q '\.debug_info' \|\| die "CONFIG_DEBUG_INFO not enabled"

	init_addr2line $objfile

	DIR_PREFIX=supercalifragilisticexpialidocious
	find_dir_prefix

	FIRST=1
	while [[ $# -gt 0 ]]; do
	func_addr=$1
	shift

	# print any matches found
	DONE=0
	__faddr2line $objfile $func_addr $DIR_PREFIX 0

	# if no match was found, print warnings
	if [[ $DONE = 0 ]]; then
	__faddr2line $objfile $func_addr $DIR_PREFIX 1
	warn "no match for $func_addr"
	fi
	done