1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3# (c) 2014, Sasha Levin <[email protected]>
4#set -x
5
6if [[ $# < 1 ]]; then
7	echo "Usage:"
8	echo "	$0 <vmlinux> [base path] [modules path]"
9	exit 1
10fi
11
12vmlinux=$1
13basepath=${2-auto}
14modpath=$3
15declare -A cache
16declare -A modcache
17
18parse_symbol() {
19	# The structure of symbol at this point is:
20	#   ([name]+[offset]/[total length])
21	#
22	# For example:
23	#   do_basic_setup+0x9c/0xbf
24
25	if [[ $module == "" ]] ; then
26		local objfile=$vmlinux
27	elif [[ "${modcache[$module]+isset}" == "isset" ]]; then
28		local objfile=${modcache[$module]}
29	else
30		if [[ $modpath == "" ]]; then
31			echo "WARNING! Modules path isn't set, but is needed to parse this symbol" >&2
32			return
33		fi
34		local objfile=$(find "$modpath" -name "${module//_/[-_]}.ko*" -print -quit)
35		[[ $objfile == "" ]] && return
36		modcache[$module]=$objfile
37	fi
38
39	# Remove the englobing parenthesis
40	symbol=${symbol#\(}
41	symbol=${symbol%\)}
42
43	# Strip segment
44	local segment
45	if [[ $symbol == *:* ]] ; then
46		segment=${symbol%%:*}:
47		symbol=${symbol#*:}
48	fi
49
50	# Strip the symbol name so that we could look it up
51	local name=${symbol%+*}
52
53	# Use 'nm vmlinux' to figure out the base address of said symbol.
54	# It's actually faster to call it every time than to load it
55	# all into bash.
56	if [[ "${cache[$module,$name]+isset}" == "isset" ]]; then
57		local base_addr=${cache[$module,$name]}
58	else
59		local base_addr=$(nm "$objfile" | awk '$3 == "'$name'" && ($2 == "t" || $2 == "T") {print $1; exit}')
60		if [[ $base_addr == "" ]] ; then
61			# address not found
62			return
63		fi
64		cache[$module,$name]="$base_addr"
65	fi
66	# Let's start doing the math to get the exact address into the
67	# symbol. First, strip out the symbol total length.
68	local expr=${symbol%/*}
69
70	# Now, replace the symbol name with the base address we found
71	# before.
72	expr=${expr/$name/0x$base_addr}
73
74	# Evaluate it to find the actual address
75	expr=$((expr))
76	local address=$(printf "%x\n" "$expr")
77
78	# Pass it to addr2line to get filename and line number
79	# Could get more than one result
80	if [[ "${cache[$module,$address]+isset}" == "isset" ]]; then
81		local code=${cache[$module,$address]}
82	else
83		local code=$(${CROSS_COMPILE}addr2line -i -e "$objfile" "$address")
84		cache[$module,$address]=$code
85	fi
86
87	# addr2line doesn't return a proper error code if it fails, so
88	# we detect it using the value it prints so that we could preserve
89	# the offset/size into the function and bail out
90	if [[ $code == "??:0" ]]; then
91		return
92	fi
93
94	# Strip out the base of the path on each line
95	code=$(while read -r line; do echo "${line#$basepath/}"; done <<< "$code")
96
97	# In the case of inlines, move everything to same line
98	code=${code//$'\n'/' '}
99
100	# Replace old address with pretty line numbers
101	symbol="$segment$name ($code)"
102}
103
104decode_code() {
105	local scripts=`dirname "${BASH_SOURCE[0]}"`
106
107	echo "$1" | $scripts/decodecode
108}
109
110handle_line() {
111	local words
112
113	# Tokenize
114	read -a words <<<"$1"
115
116	# Remove hex numbers. Do it ourselves until it happens in the
117	# kernel
118
119	# We need to know the index of the last element before we
120	# remove elements because arrays are sparse
121	local last=$(( ${#words[@]} - 1 ))
122
123	for i in "${!words[@]}"; do
124		# Remove the address
125		if [[ ${words[$i]} =~ \[\<([^]]+)\>\] ]]; then
126			unset words[$i]
127		fi
128
129		# Format timestamps with tabs
130		if [[ ${words[$i]} == \[ && ${words[$i+1]} == *\] ]]; then
131			unset words[$i]
132			words[$i+1]=$(printf "[%13s\n" "${words[$i+1]}")
133		fi
134	done
135
136	if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then
137		module=${words[$last]}
138		module=${module#\[}
139		module=${module%\]}
140		symbol=${words[$last-1]}
141		unset words[$last-1]
142	else
143		# The symbol is the last element, process it
144		symbol=${words[$last]}
145		module=
146	fi
147
148	unset words[$last]
149	parse_symbol # modifies $symbol
150
151	# Add up the line number to the symbol
152	echo "${words[@]}" "$symbol $module"
153}
154
155if [[ $basepath == "auto" ]] ; then
156	module=""
157	symbol="kernel_init+0x0/0x0"
158	parse_symbol
159	basepath=${symbol#kernel_init (}
160	basepath=${basepath%/init/main.c:*)}
161fi
162
163while read line; do
164	# Let's see if we have an address in the line
165	if [[ $line =~ \[\<([^]]+)\>\] ]] ||
166	   [[ $line =~ [^+\ ]+\+0x[0-9a-f]+/0x[0-9a-f]+ ]]; then
167		# Translate address to line numbers
168		handle_line "$line"
169	# Is it a code line?
170	elif [[ $line == *Code:* ]]; then
171		decode_code "$line"
172	else
173		# Nothing special in this line, show it as is
174		echo "$line"
175	fi
176done
177