2 # SPDX-License-Identifier: GPL-2.0
4 # Translate stack dump function offsets.
6 # addr2line doesn't work with KASLR addresses. This works similarly to
7 # addr2line, but instead takes the 'func+0x123' format as input:
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
13 # If the address is part of an inlined function, the full inline call chain is
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
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:
27 # $ ./scripts/faddr2line ~/k/vmlinux raw_ioctl+0x5
29 # raw_ioctl at drivers/char/raw.c:122
32 # raw_ioctl at net/ipv4/raw.c:876
34 # Multiple addresses can be specified on a single command line:
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
40 # free_reserved_area+0x90/0x123:
41 # free_reserved_area at mm/page_alloc.c:6429 (discriminator 2)
48 echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
61 READELF="${CROSS_COMPILE:-}readelf"
62 ADDR2LINE="${CROSS_COMPILE:-}addr2line"
65 command -v ${AWK} >/dev/null 2>&1 || die "${AWK} isn't installed"
66 command -v ${READELF} >/dev/null 2>&1 || die "${READELF} isn't installed"
67 command -v ${ADDR2LINE} >/dev/null 2>&1 || die "${ADDR2LINE} isn't installed"
69 # Try to figure out the source directory prefix so we can remove it from the
70 # addr2line output. HACK ALERT: This assumes that start_kernel() is in
71 # init/main.c! This only works for vmlinux. Otherwise it falls back to
72 # printing the absolute path.
76 local start_kernel_addr=$(${READELF} --symbols --wide $objfile | ${AWK} '$8 == "start_kernel" {printf "0x%s", $2}')
77 [[ -z $start_kernel_addr ]] && return
79 local file_line=$(${ADDR2LINE} -e $objfile $start_kernel_addr)
80 [[ -z $file_line ]] && return
82 local prefix=${file_line%init/main.c:*}
83 if [[ -z $prefix ]] || [[ $prefix = $file_line ]]; then
95 local print_warnings=$4
97 local sym_name=${func_addr%+*}
98 local offset=${func_addr#*+}
101 [[ $func_addr =~ "/" ]] && user_size=${func_addr#*/}
103 if [[ -z $sym_name ]] || [[ -z $offset ]] || [[ $sym_name = $func_addr ]]; then
104 warn "bad func+offset $func_addr"
109 # Go through each of the object's symbols which match the func name.
110 # In rare cases there might be duplicates, in which case we print all
114 local sym_addr=0x${fields[1]}
115 local sym_elf_size=${fields[2]}
116 local sym_sec=${fields[6]}
118 # Get the section size:
119 local sec_size=$(${READELF} --section-headers --wide $objfile |
121 ${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')
123 if [[ -z $sec_size ]]; then
124 warn "bad section size: section: $sym_sec"
129 # Calculate the symbol size.
131 # Unfortunately we can't use the ELF size, because kallsyms
132 # also includes the padding bytes in its size calculation. For
133 # kallsyms, the size calculation is the distance between the
134 # symbol and the next symbol in a sorted list.
140 cur_sym_addr=0x${fields[1]}
141 local cur_sym_elf_size=${fields[2]}
142 local cur_sym_name=${fields[7]:-}
144 if [[ $cur_sym_addr = $sym_addr ]] &&
145 [[ $cur_sym_elf_size = $sym_elf_size ]] &&
146 [[ $cur_sym_name = $sym_name ]]; then
151 if [[ $found = 1 ]]; then
152 sym_size=$(($cur_sym_addr - $sym_addr))
153 [[ $sym_size -lt $sym_elf_size ]] && continue;
157 done < <(${READELF} --symbols --wide $objfile | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)
159 if [[ $found = 0 ]]; then
160 warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size"
165 # If nothing was found after the symbol, assume it's the last
166 # symbol in the section.
167 [[ $found = 1 ]] && sym_size=$(($sec_size - $sym_addr))
169 if [[ -z $sym_size ]] || [[ $sym_size -le 0 ]]; then
170 warn "bad symbol size: sym_addr: $sym_addr cur_sym_addr: $cur_sym_addr"
175 sym_size=0x$(printf %x $sym_size)
177 # Calculate the section address from user-supplied offset:
178 local addr=$(($sym_addr + $offset))
179 if [[ -z $addr ]] || [[ $addr = 0 ]]; then
180 warn "bad address: $sym_addr + $offset"
184 addr=0x$(printf %x $addr)
186 # If the user provided a size, make sure it matches the symbol's size:
187 if [[ -n $user_size ]] && [[ $user_size -ne $sym_size ]]; then
188 [[ $print_warnings = 1 ]] &&
189 echo "skipping $sym_name address at $addr due to size mismatch ($user_size != $sym_size)"
193 # Make sure the provided offset is within the symbol's range:
194 if [[ $offset -gt $sym_size ]]; then
195 [[ $print_warnings = 1 ]] &&
196 echo "skipping $sym_name address at $addr due to size mismatch ($offset > $sym_size)"
200 # In case of duplicates or multiple addresses specified on the
201 # cmdline, separate multiple entries with a blank line:
202 [[ $FIRST = 0 ]] && echo
205 echo "$sym_name+$offset/$sym_size:"
207 # Pass section address to addr2line and strip absolute paths
209 local output=$(${ADDR2LINE} -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;")
210 [[ -z $output ]] && continue
212 # Default output (non --list):
213 if [[ $LIST = 0 ]]; then
214 echo "$output" | while read -r line
222 # For --list, show each line with its corresponding source code:
223 echo "$output" | while read -r line
227 n=$(echo $line | sed 's/.*:\([0-9]\+\).*/\1/g')
230 f=$(echo $line | sed 's/.*at \(.\+\):.*/\1/g')
231 ${AWK} 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
236 done < <(${READELF} --symbols --wide $objfile | ${AWK} -v fn=$sym_name '$4 == "FUNC" && $8 == fn')
239 [[ $# -lt 2 ]] && usage
244 [[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1
246 [[ ! -f $objfile ]] && die "can't find objfile $objfile"
249 DIR_PREFIX=supercalifragilisticexpialidocious
250 find_dir_prefix $objfile
253 while [[ $# -gt 0 ]]; do
257 # print any matches found
259 __faddr2line $objfile $func_addr $DIR_PREFIX 0
261 # if no match was found, print warnings
262 if [[ $DONE = 0 ]]; then
263 __faddr2line $objfile $func_addr $DIR_PREFIX 1
264 warn "no match for $func_addr"