[linux.git] / scripts / faddr2line

#!/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

READELF="${CROSS_COMPILE:-}readelf"
ADDR2LINE="${CROSS_COMPILE:-}addr2line"
SIZE="${CROSS_COMPILE:-}size"
NM="${CROSS_COMPILE:-}nm"

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"
command -v ${SIZE} >/dev/null 2>&1 || die "size isn't installed"
command -v ${NM} >/dev/null 2>&1 || die "nm isn't installed"

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
}

# 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 objfile=$1

	local start_kernel_addr=$(${READELF} -sW $objfile | awk '$8 == "start_kernel" {printf "0x%s", $2}')
	[[ -z $start_kernel_addr ]] && return

	local file_line=$(${ADDR2LINE} -e $objfile $start_kernel_addr)
	[[ -z $file_line ]] && return

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

	DIR_PREFIX=$prefix
	return 0
}

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

	local func=${func_addr%+*}
	local offset=${func_addr#*+}
	offset=${offset%/*}
	local size=
	[[ $func_addr =~ "/" ]] && size=${func_addr#*/}

	if [[ -z $func ]] || [[ -z $offset ]] || [[ $func = $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.
	file_end=$(${SIZE} -Ax $objfile | awk '$1 == ".text" {print $2}')
	while read symbol; do
		local fields=($symbol)
		local sym_base=0x${fields[0]}
		local sym_type=${fields[1]}
		local sym_end=${fields[3]}

		# calculate the size
		local sym_size=$(($sym_end - $sym_base))
		if [[ -z $sym_size ]] || [[ $sym_size -le 0 ]]; then
			warn "bad symbol size: base: $sym_base end: $sym_end"
			DONE=1
			return
		fi
		sym_size=0x$(printf %x $sym_size)

		# calculate the address
		local addr=$(($sym_base + $offset))
		if [[ -z $addr ]] || [[ $addr = 0 ]]; then
			warn "bad address: $sym_base + $offset"
			DONE=1
			return
		fi
		addr=0x$(printf %x $addr)

		# weed out non-function symbols
		if [[ $sym_type != t ]] && [[ $sym_type != T ]]; then
			[[ $print_warnings = 1 ]] &&
				echo "skipping $func address at $addr due to non-function symbol of type '$sym_type'"
			continue
		fi

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

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

		# separate multiple entries with a blank line
		[[ $FIRST = 0 ]] && echo
		FIRST=0

		# pass real address to addr2line
		echo "$func+$offset/$sym_size:"
		local file_lines=$(${ADDR2LINE} -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;")
		[[ -z $file_lines ]] && return

		if [[ $LIST = 0 ]]; then
			echo "$file_lines" | while read -r line
			do
				echo $line
			done
			DONE=1;
			return
		fi

		# show each line with context
		echo "$file_lines" | 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 < <(${NM} -n $objfile | awk -v fn=$func -v end=$file_end '$3 == fn { found=1; line=$0; start=$1; next } found == 1 { found=0; print line, "0x"$1 } END {if (found == 1) print line, end; }')
}

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

objfile=$1

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

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

DIR_PREFIX=supercalifragilisticexpialidocious
find_dir_prefix $objfile

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
Commit	Line	Data
67326666	1	#!/bin/bash
b2441318	2	# SPDX-License-Identifier: GPL-2.0
67326666 JP	3	#
	4	# Translate stack dump function offsets.
	5	#
	6	# addr2line doesn't work with KASLR addresses. This works similarly to
	7	# addr2line, but instead takes the 'func+0x123' format as input:
	8	#
	9	# $ ./scripts/faddr2line ~/k/vmlinux meminfo_proc_show+0x5/0x568
	10	# meminfo_proc_show+0x5/0x568:
	11	# meminfo_proc_show at fs/proc/meminfo.c:27
	12	#
	13	# If the address is part of an inlined function, the full inline call chain is
	14	# printed:
	15	#
	16	# $ ./scripts/faddr2line ~/k/vmlinux native_write_msr+0x6/0x27
	17	# native_write_msr+0x6/0x27:
	18	# arch_static_branch at arch/x86/include/asm/msr.h:121
	19	# (inlined by) static_key_false at include/linux/jump_label.h:125
	20	# (inlined by) native_write_msr at arch/x86/include/asm/msr.h:125
	21	#
	22	# The function size after the '/' in the input is optional, but recommended.
	23	# It's used to help disambiguate any duplicate symbol names, which can occur
	24	# rarely. If the size is omitted for a duplicate symbol then it's possible for
	25	# multiple code sites to be printed:
	26	#
	27	# $ ./scripts/faddr2line ~/k/vmlinux raw_ioctl+0x5
	28	# raw_ioctl+0x5/0x20:
	29	# raw_ioctl at drivers/char/raw.c:122
	30	#
	31	# raw_ioctl+0x5/0xb1:
	32	# raw_ioctl at net/ipv4/raw.c:876
	33	#
	34	# Multiple addresses can be specified on a single command line:
	35	#
	36	# $ ./scripts/faddr2line ~/k/vmlinux type_show+0x10/45 free_reserved_area+0x90
	37	# type_show+0x10/0x2d:
	38	# type_show at drivers/video/backlight/backlight.c:213
	39	#
	40	# free_reserved_area+0x90/0x123:
	41	# free_reserved_area at mm/page_alloc.c:6429 (discriminator 2)
	42
	43
	44	set -o errexit
	45	set -o nounset
	46
4cc90b4c LC	47	READELF="${CROSS_COMPILE:-}readelf"
	48	ADDR2LINE="${CROSS_COMPILE:-}addr2line"
	49	SIZE="${CROSS_COMPILE:-}size"
	50	NM="${CROSS_COMPILE:-}nm"
95a87982	51
67326666	52	command -v awk >/dev/null 2>&1 \|\| die "awk isn't installed"
95a87982 LC	53	command -v ${READELF} >/dev/null 2>&1 \|\| die "readelf isn't installed"
	54	command -v ${ADDR2LINE} >/dev/null 2>&1 \|\| die "addr2line isn't installed"
	55	command -v ${SIZE} >/dev/null 2>&1 \|\| die "size isn't installed"
	56	command -v ${NM} >/dev/null 2>&1 \|\| die "nm isn't installed"
67326666 JP	57
67326666 JP	58	usage() {
689135f0	59	echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
67326666 JP	60	exit 1
	61	}
	62
	63	warn() {
	64	echo "$1" >&2
	65	}
	66
	67	die() {
	68	echo "ERROR: $1" >&2
	69	exit 1
	70	}
	71
	72	# Try to figure out the source directory prefix so we can remove it from the
	73	# addr2line output. HACK ALERT: This assumes that start_kernel() is in
f5f67cc0	74	# init/main.c! This only works for vmlinux. Otherwise it falls back to
67326666 JP	75	# printing the absolute path.
	76	find_dir_prefix() {
	77	local objfile=$1
	78
95a87982	79	local start_kernel_addr=$(${READELF} -sW $objfile \| awk '$8 == "start_kernel" {printf "0x%s", $2}')
67326666 JP	80	[[ -z $start_kernel_addr ]] && return
67326666 JP	81
95a87982	82	local file_line=$(${ADDR2LINE} -e $objfile $start_kernel_addr)
67326666 JP	83	[[ -z $file_line ]] && return
	84
	85	local prefix=${file_line%init/main.c:*}
	86	if [[ -z $prefix ]] \|\| [[ $prefix = $file_line ]]; then
	87	return
	88	fi
	89
	90	DIR_PREFIX=$prefix
	91	return 0
	92	}
	93
	94	__faddr2line() {
	95	local objfile=$1
	96	local func_addr=$2
	97	local dir_prefix=$3
	98	local print_warnings=$4
	99
	100	local func=${func_addr%+*}
	101	local offset=${func_addr#*+}
	102	offset=${offset%/*}
	103	local size=
	104	[[ $func_addr =~ "/" ]] && size=${func_addr#*/}
	105
	106	if [[ -z $func ]] \|\| [[ -z $offset ]] \|\| [[ $func = $func_addr ]]; then
	107	warn "bad func+offset $func_addr"
	108	DONE=1
	109	return
	110	fi
	111
	112	# Go through each of the object's symbols which match the func name.
	113	# In rare cases there might be duplicates.
95a87982	114	file_end=$(${SIZE} -Ax $objfile \| awk '$1 == ".text" {print $2}')
67326666 JP	115	while read symbol; do
67326666 JP	116	local fields=($symbol)
efdb4167 JP	117	local sym_base=0x${fields[0]}
efdb4167 JP	118	local sym_type=${fields[1]}
2aab9c3c	119	local sym_end=${fields[3]}
efdb4167 JP	120
	121	# calculate the size
	122	local sym_size=$(($sym_end - $sym_base))
	123	if [[ -z $sym_size ]] \|\| [[ $sym_size -le 0 ]]; then
	124	warn "bad symbol size: base: $sym_base end: $sym_end"
	125	DONE=1
	126	return
	127	fi
	128	sym_size=0x$(printf %x $sym_size)
67326666 JP	129
	130	# calculate the address
	131	local addr=$(($sym_base + $offset))
	132	if [[ -z $addr ]] \|\| [[ $addr = 0 ]]; then
	133	warn "bad address: $sym_base + $offset"
	134	DONE=1
	135	return
	136	fi
efdb4167	137	addr=0x$(printf %x $addr)
67326666 JP	138
67326666 JP	139	# weed out non-function symbols
efdb4167	140	if [[ $sym_type != t ]] && [[ $sym_type != T ]]; then
67326666	141	[[ $print_warnings = 1 ]] &&
efdb4167	142	echo "skipping $func address at $addr due to non-function symbol of type '$sym_type'"
67326666 JP	143	continue
	144	fi
	145
	146	# if the user provided a size, make sure it matches the symbol's size
	147	if [[ -n $size ]] && [[ $size -ne $sym_size ]]; then
	148	[[ $print_warnings = 1 ]] &&
efdb4167	149	echo "skipping $func address at $addr due to size mismatch ($size != $sym_size)"
67326666 JP	150	continue;
	151	fi
	152
	153	# make sure the provided offset is within the symbol's range
	154	if [[ $offset -gt $sym_size ]]; then
	155	[[ $print_warnings = 1 ]] &&
efdb4167	156	echo "skipping $func address at $addr due to size mismatch ($offset > $sym_size)"
67326666 JP	157	continue
	158	fi
	159
	160	# separate multiple entries with a blank line
	161	[[ $FIRST = 0 ]] && echo
	162	FIRST=0
	163
efdb4167 JP	164	# pass real address to addr2line
efdb4167 JP	165	echo "$func+$offset/$sym_size:"
6870c016 CD	166	local file_lines=$(${ADDR2LINE} -fpie $objfile $addr \| sed "s; $dir_prefix\(\./\)*; ;")
	167	[[ -z $file_lines ]] && return
	168
689135f0 PZI	169	if [[ $LIST = 0 ]]; then
	170	echo "$file_lines" \| while read -r line
	171	do
	172	echo $line
	173	done
	174	DONE=1;
	175	return
	176	fi
	177
6870c016 CD	178	# show each line with context
	179	echo "$file_lines" \| while read -r line
	180	do
689135f0	181	echo
6870c016	182	echo $line
78eb0c63 CD	183	n=$(echo $line \| sed 's/.:\([0-9]\+\)./\1/g')
	184	n1=$[$n-5]
	185	n2=$[$n+5]
	186	f=$(echo $line \| sed 's/.at \(.\+\):./\1/g')
689135f0	187	awk 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
6870c016 CD	188	done
6870c016 CD	189
67326666 JP	190	DONE=1
67326666 JP	191
95a87982	192	done < <(${NM} -n $objfile \| awk -v fn=$func -v end=$file_end '$3 == fn { found=1; line=$0; start=$1; next } found == 1 { found=0; print line, "0x"$1 } END {if (found == 1) print line, end; }')
67326666 JP	193	}
	194
	195	[[ $# -lt 2 ]] && usage
	196
	197	objfile=$1
689135f0 PZI	198
	199	LIST=0
	200	[[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1
	201
67326666 JP	202	[[ ! -f $objfile ]] && die "can't find objfile $objfile"
	203	shift
	204
	205	DIR_PREFIX=supercalifragilisticexpialidocious
	206	find_dir_prefix $objfile
	207
	208	FIRST=1
	209	while [[ $# -gt 0 ]]; do
	210	func_addr=$1
	211	shift
	212
	213	# print any matches found
	214	DONE=0
	215	__faddr2line $objfile $func_addr $DIR_PREFIX 0
	216
	217	# if no match was found, print warnings
	218	if [[ $DONE = 0 ]]; then
	219	__faddr2line $objfile $func_addr $DIR_PREFIX 1
	220	warn "no match for $func_addr"
	221	fi
	222	done