scripts/faddr2line: Use LLVM addr2line and readelf if LLVM=1
[linux-2.6-block.git] / scripts / faddr2line
CommitLineData
67326666 1#!/bin/bash
b2441318 2# SPDX-License-Identifier: GPL-2.0
67326666
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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
44set -o errexit
45set -o nounset
46
67326666 47usage() {
689135f0 48 echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
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49 exit 1
50}
51
52warn() {
53 echo "$1" >&2
54}
55
56die() {
57 echo "ERROR: $1" >&2
58 exit 1
59}
60
86bf86e1
WD
61UTIL_SUFFIX=""
62if [[ "${LLVM:-}" == "" ]]; then
63 UTIL_PREFIX=${CROSS_COMPILE:-}
64else
65 UTIL_PREFIX=llvm-
66
67 if [[ "${LLVM}" == *"/" ]]; then
68 UTIL_PREFIX=${LLVM}${UTIL_PREFIX}
69 elif [[ "${LLVM}" == "-"* ]]; then
70 UTIL_SUFFIX=${LLVM}
71 fi
72fi
73
74READELF="${UTIL_PREFIX}readelf${UTIL_SUFFIX}"
75ADDR2LINE="${UTIL_PREFIX}addr2line${UTIL_SUFFIX}"
1d1a0e7c 76AWK="awk"
a41a2e2e 77GREP="grep"
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78
79command -v ${AWK} >/dev/null 2>&1 || die "${AWK} isn't installed"
80command -v ${READELF} >/dev/null 2>&1 || die "${READELF} isn't installed"
81command -v ${ADDR2LINE} >/dev/null 2>&1 || die "${ADDR2LINE} isn't installed"
82
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83# Try to figure out the source directory prefix so we can remove it from the
84# addr2line output. HACK ALERT: This assumes that start_kernel() is in
f5f67cc0 85# init/main.c! This only works for vmlinux. Otherwise it falls back to
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86# printing the absolute path.
87find_dir_prefix() {
88 local objfile=$1
89
2d77de15
SD
90 local start_kernel_addr=$(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' |
91 ${AWK} '$8 == "start_kernel" {printf "0x%s", $2}')
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92 [[ -z $start_kernel_addr ]] && return
93
95a87982 94 local file_line=$(${ADDR2LINE} -e $objfile $start_kernel_addr)
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95 [[ -z $file_line ]] && return
96
97 local prefix=${file_line%init/main.c:*}
98 if [[ -z $prefix ]] || [[ $prefix = $file_line ]]; then
99 return
100 fi
101
102 DIR_PREFIX=$prefix
103 return 0
104}
105
106__faddr2line() {
107 local objfile=$1
108 local func_addr=$2
109 local dir_prefix=$3
110 local print_warnings=$4
111
1d1a0e7c 112 local sym_name=${func_addr%+*}
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113 local func_offset=${func_addr#*+}
114 func_offset=${func_offset%/*}
1d1a0e7c 115 local user_size=
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116 local file_type
117 local is_vmlinux=0
1d1a0e7c 118 [[ $func_addr =~ "/" ]] && user_size=${func_addr#*/}
67326666 119
dcea997b 120 if [[ -z $sym_name ]] || [[ -z $func_offset ]] || [[ $sym_name = $func_addr ]]; then
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121 warn "bad func+offset $func_addr"
122 DONE=1
123 return
124 fi
125
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126 # vmlinux uses absolute addresses in the section table rather than
127 # section offsets.
128 local file_type=$(${READELF} --file-header $objfile |
129 ${AWK} '$1 == "Type:" { print $2; exit }')
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130 if [[ $file_type = "EXEC" ]] || [[ $file_type == "DYN" ]]; then
131 is_vmlinux=1
132 fi
dcea997b 133
67326666 134 # Go through each of the object's symbols which match the func name.
1d1a0e7c
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135 # In rare cases there might be duplicates, in which case we print all
136 # matches.
137 while read line; do
138 local fields=($line)
139 local sym_addr=0x${fields[1]}
140 local sym_elf_size=${fields[2]}
141 local sym_sec=${fields[6]}
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142 local sec_size
143 local sec_name
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144
145 # Get the section size:
dcea997b 146 sec_size=$(${READELF} --section-headers --wide $objfile |
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147 sed 's/\[ /\[/' |
148 ${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')
149
150 if [[ -z $sec_size ]]; then
151 warn "bad section size: section: $sym_sec"
152 DONE=1
153 return
154 fi
155
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156 # Get the section name:
157 sec_name=$(${READELF} --section-headers --wide $objfile |
158 sed 's/\[ /\[/' |
159 ${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print $2; exit }')
160
161 if [[ -z $sec_name ]]; then
162 warn "bad section name: section: $sym_sec"
163 DONE=1
164 return
165 fi
166
1d1a0e7c
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167 # Calculate the symbol size.
168 #
169 # Unfortunately we can't use the ELF size, because kallsyms
170 # also includes the padding bytes in its size calculation. For
171 # kallsyms, the size calculation is the distance between the
172 # symbol and the next symbol in a sorted list.
173 local sym_size
174 local cur_sym_addr
175 local found=0
176 while read line; do
177 local fields=($line)
178 cur_sym_addr=0x${fields[1]}
179 local cur_sym_elf_size=${fields[2]}
180 local cur_sym_name=${fields[7]:-}
181
182 if [[ $cur_sym_addr = $sym_addr ]] &&
183 [[ $cur_sym_elf_size = $sym_elf_size ]] &&
184 [[ $cur_sym_name = $sym_name ]]; then
185 found=1
186 continue
187 fi
188
189 if [[ $found = 1 ]]; then
190 sym_size=$(($cur_sym_addr - $sym_addr))
191 [[ $sym_size -lt $sym_elf_size ]] && continue;
192 found=2
193 break
194 fi
2d77de15 195 done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)
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196
197 if [[ $found = 0 ]]; then
198 warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size"
199 DONE=1
200 return
201 fi
202
203 # If nothing was found after the symbol, assume it's the last
204 # symbol in the section.
205 [[ $found = 1 ]] && sym_size=$(($sec_size - $sym_addr))
206
efdb4167 207 if [[ -z $sym_size ]] || [[ $sym_size -le 0 ]]; then
1d1a0e7c 208 warn "bad symbol size: sym_addr: $sym_addr cur_sym_addr: $cur_sym_addr"
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209 DONE=1
210 return
211 fi
1d1a0e7c 212
efdb4167 213 sym_size=0x$(printf %x $sym_size)
67326666 214
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215 # Calculate the address from user-supplied offset:
216 local addr=$(($sym_addr + $func_offset))
67326666 217 if [[ -z $addr ]] || [[ $addr = 0 ]]; then
dcea997b 218 warn "bad address: $sym_addr + $func_offset"
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219 DONE=1
220 return
221 fi
efdb4167 222 addr=0x$(printf %x $addr)
67326666 223
1d1a0e7c
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224 # If the user provided a size, make sure it matches the symbol's size:
225 if [[ -n $user_size ]] && [[ $user_size -ne $sym_size ]]; then
67326666 226 [[ $print_warnings = 1 ]] &&
1d1a0e7c 227 echo "skipping $sym_name address at $addr due to size mismatch ($user_size != $sym_size)"
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228 continue;
229 fi
230
1d1a0e7c 231 # Make sure the provided offset is within the symbol's range:
dcea997b 232 if [[ $func_offset -gt $sym_size ]]; then
67326666 233 [[ $print_warnings = 1 ]] &&
dcea997b 234 echo "skipping $sym_name address at $addr due to size mismatch ($func_offset > $sym_size)"
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235 continue
236 fi
237
1d1a0e7c
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238 # In case of duplicates or multiple addresses specified on the
239 # cmdline, separate multiple entries with a blank line:
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240 [[ $FIRST = 0 ]] && echo
241 FIRST=0
242
dcea997b 243 echo "$sym_name+$func_offset/$sym_size:"
6870c016 244
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245 # Pass section address to addr2line and strip absolute paths
246 # from the output:
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247 local args="--functions --pretty-print --inlines --exe=$objfile"
248 [[ $is_vmlinux = 0 ]] && args="$args --section=$sec_name"
249 local output=$(${ADDR2LINE} $args $addr | sed "s; $dir_prefix\(\./\)*; ;")
1d1a0e7c
JP
250 [[ -z $output ]] && continue
251
252 # Default output (non --list):
689135f0 253 if [[ $LIST = 0 ]]; then
1d1a0e7c 254 echo "$output" | while read -r line
689135f0
PZI
255 do
256 echo $line
257 done
258 DONE=1;
1d1a0e7c 259 continue
689135f0
PZI
260 fi
261
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262 # For --list, show each line with its corresponding source code:
263 echo "$output" | while read -r line
6870c016 264 do
689135f0 265 echo
6870c016 266 echo $line
78eb0c63
CD
267 n=$(echo $line | sed 's/.*:\([0-9]\+\).*/\1/g')
268 n1=$[$n-5]
269 n2=$[$n+5]
270 f=$(echo $line | sed 's/.*at \(.\+\):.*/\1/g')
1d1a0e7c 271 ${AWK} 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
6870c016
CD
272 done
273
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274 DONE=1
275
180af1a5 276 done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$8 == fn')
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277}
278
279[[ $# -lt 2 ]] && usage
280
281objfile=$1
689135f0
PZI
282
283LIST=0
284[[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1
285
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286[[ ! -f $objfile ]] && die "can't find objfile $objfile"
287shift
288
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289${READELF} --section-headers --wide $objfile | ${GREP} -q '\.debug_info' || die "CONFIG_DEBUG_INFO not enabled"
290
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291DIR_PREFIX=supercalifragilisticexpialidocious
292find_dir_prefix $objfile
293
294FIRST=1
295while [[ $# -gt 0 ]]; do
296 func_addr=$1
297 shift
298
299 # print any matches found
300 DONE=0
301 __faddr2line $objfile $func_addr $DIR_PREFIX 0
302
303 # if no match was found, print warnings
304 if [[ $DONE = 0 ]]; then
305 __faddr2line $objfile $func_addr $DIR_PREFIX 1
306 warn "no match for $func_addr"
307 fi
308done