Commit 26681eb3 authored by Stephen Boyd's avatar Stephen Boyd Committed by Linus Torvalds
Browse files

scripts/decode_stacktrace.sh: support debuginfod 

Now that stacktraces contain the build ID information we can update this
script to use debuginfod-find to locate the debuginfo for the vmlinux and
modules automatically.  This can replace the existing code that requires
specifying a path to vmlinux or tries to find the vmlinux and modules
automatically by using the release number.  Work it into the script as a
fallback option if the vmlinux isn't specified on the commandline.

Link: https://lkml.kernel.org/r/20210511003845.2429846-9-swboyd@chromium.org


Signed-off-by: default avatarStephen Boyd <swboyd@chromium.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 9ef8af2a

scripts/decode_stacktrace.sh

+70 −11
Original line number Diff line number Diff line
@@ -3,11 +3,10 @@ 
# (c) 2014, Sasha Levin <sasha.levin@oracle.com>

#set -x



if [[ $# < 1 ]]; then

usage() {

	echo "Usage:"

	echo "	$0 -r <release> | <vmlinux> [base path] [modules path]"

	exit 1

fi

}



if [[ $1 == "-r" ]] ; then

	vmlinux=""
@@ -24,6 +23,7 @@ if [[ $1 == "-r" ]] ; then 


	if [[ $vmlinux == "" ]] ; then

		echo "ERROR! vmlinux image for release $release is not found" >&2

		usage

		exit 2

	fi

else
@@ -31,12 +31,35 @@ else 
	basepath=${2-auto}

	modpath=$3

	release=""

	debuginfod=



	# Can we use debuginfod-find?

	if type debuginfod-find >/dev/null 2>&1 ; then

		debuginfod=${1-only}

	fi



	if [[ $vmlinux == "" && -z $debuginfod ]] ; then

		echo "ERROR! vmlinux image must be specified" >&2

		usage

		exit 1

	fi

fi



declare -A cache

declare -A modcache



find_module() {

	if [[ -n $debuginfod ]] ; then

		if [[ -n $modbuildid ]] ; then

			debuginfod-find debuginfo $modbuildid && return

		fi



		# Only using debuginfod so don't try to find vmlinux module path

		if [[ $debuginfod == "only" ]] ; then

			return

		fi

	fi



	if [[ "$modpath" != "" ]] ; then

		for fn in $(find "$modpath" -name "${module//_/[-_]}.ko*") ; do

			if readelf -WS "$fn" | grep -qwF .debug_line ; then
@@ -150,6 +173,27 @@ parse_symbol() { 
	symbol="$segment$name ($code)"

}



debuginfod_get_vmlinux() {

	local vmlinux_buildid=${1##* }



	if [[ $vmlinux != "" ]]; then

		return

	fi



	if [[ $vmlinux_buildid =~ ^[0-9a-f]+ ]]; then

		vmlinux=$(debuginfod-find debuginfo $vmlinux_buildid)

		if [[ $? -ne 0 ]] ; then

			echo "ERROR! vmlinux image not found via debuginfod-find" >&2

			usage

			exit 2

		fi

		return

	fi

	echo "ERROR! Build ID for vmlinux not found. Try passing -r or specifying vmlinux" >&2

	usage

	exit 2

}



decode_code() {

	local scripts=`dirname "${BASH_SOURCE[0]}"`
@@ -157,6 +201,14 @@ decode_code() { 
}



handle_line() {

	if [[ $basepath == "auto" && $vmlinux != "" ]] ; then

		module=""

		symbol="kernel_init+0x0/0x0"

		parse_symbol

		basepath=${symbol#kernel_init (}

		basepath=${basepath%/init/main.c:*)}

	fi



	local words



	# Tokenize
@@ -182,16 +234,28 @@ handle_line() { 
		fi

	done



	if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then

		words[$last-1]="${words[$last-1]} ${words[$last]}"

		unset words[$last]

		last=$(( $last - 1 ))

	fi



	if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then

		module=${words[$last]}

		module=${module#\[}

		module=${module%\]}

		modbuildid=${module#* }

		module=${module% *}

		if [[ $modbuildid == $module ]]; then

			modbuildid=

		fi

		symbol=${words[$last-1]}

		unset words[$last-1]

	else

		# The symbol is the last element, process it

		symbol=${words[$last]}

		module=

		modbuildid=

	fi



	unset words[$last]
@@ -201,14 +265,6 @@ handle_line() { 
	echo "${words[@]}" "$symbol $module"

}



if [[ $basepath == "auto" ]] ; then

	module=""

	symbol="kernel_init+0x0/0x0"

	parse_symbol

	basepath=${symbol#kernel_init (}

	basepath=${basepath%/init/main.c:*)}

fi



while read line; do

	# Let's see if we have an address in the line

	if [[ $line =~ \[\<([^]]+)\>\] ]] ||
@@ -218,6 +274,9 @@ while read line; do 
	# Is it a code line?

	elif [[ $line == *Code:* ]]; then

		decode_code "$line"

	# Is it a version line?

	elif [[ -n $debuginfod && $line =~ PID:\ [0-9]+\ Comm: ]]; then

		debuginfod_get_vmlinux "$line"

	else

		# Nothing special in this line, show it as is

		echo "$line"