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-rwxr-xr-xscripts/faddr2line292
1 files changed, 292 insertions, 0 deletions
diff --git a/scripts/faddr2line b/scripts/faddr2line
new file mode 100755
index 000000000..9e730b805
--- /dev/null
+++ b/scripts/faddr2line
@@ -0,0 +1,292 @@
+#!/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: $1" >&2
+ exit 1
+}
+
+READELF="${CROSS_COMPILE:-}readelf"
+ADDR2LINE="${CROSS_COMPILE:-}addr2line"
+AWK="awk"
+
+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 objfile=$1
+
+ local start_kernel_addr=$(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' |
+ ${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=$4
+
+ local sym_name=${func_addr%+*}
+ local func_offset=${func_addr#*+}
+ func_offset=${func_offset%/*}
+ local user_size=
+ local file_type
+ local is_vmlinux=0
+ [[ $func_addr =~ "/" ]] && user_size=${func_addr#*/}
+
+ if [[ -z $sym_name ]] || [[ -z $func_offset ]] || [[ $sym_name = $func_addr ]]; then
+ warn "bad func+offset $func_addr"
+ DONE=1
+ return
+ fi
+
+ # vmlinux uses absolute addresses in the section table rather than
+ # section offsets.
+ local file_type=$(${READELF} --file-header $objfile |
+ ${AWK} '$1 == "Type:" { print $2; exit }')
+ if [[ $file_type = "EXEC" ]] || [[ $file_type == "DYN" ]]; then
+ is_vmlinux=1
+ fi
+
+ # Go through each of the object's symbols which match the func name.
+ # In rare cases there might be duplicates, in which case we print all
+ # matches.
+ while read line; do
+ local fields=($line)
+ local sym_addr=0x${fields[1]}
+ local sym_elf_size=${fields[2]}
+ local sym_sec=${fields[6]}
+ local sec_size
+ local sec_name
+
+ # Get the section size:
+ sec_size=$(${READELF} --section-headers --wide $objfile |
+ sed 's/\[ /\[/' |
+ ${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')
+
+ if [[ -z $sec_size ]]; then
+ warn "bad section size: section: $sym_sec"
+ DONE=1
+ return
+ fi
+
+ # Get the section name:
+ sec_name=$(${READELF} --section-headers --wide $objfile |
+ 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]:-}
+
+ 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 $sym_elf_size ]] && continue;
+ found=2
+ break
+ fi
+ done < <(${READELF} --symbols --wide $objfile | 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:
+ local args="--functions --pretty-print --inlines --exe=$objfile"
+ [[ $is_vmlinux = 0 ]] && args="$args --section=$sec_name"
+ local output=$(${ADDR2LINE} $args $addr | 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)}' $f
+ done
+
+ DONE=1
+
+ done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$4 == "FUNC" && $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
+
+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