Commit 2bff77c6 authored by Luca Ceresoli's avatar Luca Ceresoli Committed by Andrew Morton
Browse files

scripts/decode_stacktrace.sh: fix decoding of lines with an additional info 

Since commit bdf8eafb ("arm64: stacktrace: report source of unwind
data") a stack trace line can contain an additional info field that was not
present before, in the form of one or more letters in parentheses. E.g.:

  [  504.517915]  led_sysfs_enable+0x54/0x80 (P)
                                             ^^^

When this is present, decode_stacktrace decodes the line incorrectly:

  [  504.517915] led_sysfs_enable+0x54/0x80 P

Extend parsing to decode it correctly:

  [  504.517915] led_sysfs_enable (drivers/leds/led-core.c:455 (discriminator 7)) (P)

The regex to match such lines assumes the info can be extended in the
future to other uppercase characters, and will need to be extended in case
other characters will be used. Using a much more generic regex might incur
in false positives, so this looked like a good tradeoff.

Link: https://lkml.kernel.org/r/20241230-decode_stacktrace-fix-info-v1-1-984910659173@bootlin.com


Fixes: bdf8eafb ("arm64: stacktrace: report source of unwind data")
Signed-off-by: default avatarLuca Ceresoli <luca.ceresoli@bootlin.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Puranjay Mohan <puranjay@kernel.org>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 76d5d4c5

scripts/decode_stacktrace.sh

+14 −2
Original line number Diff line number Diff line
@@ -286,6 +286,18 @@ handle_line() { 
		last=$(( $last - 1 ))

	fi



	# Extract info after the symbol if present. E.g.:

	# func_name+0x54/0x80 (P)

	#                     ^^^

	# The regex assumes only uppercase letters will be used. To be

	# extended if needed.

	local info_str=""

	if [[ ${words[$last]} =~ \([A-Z]*\) ]]; then

		info_str=${words[$last]}

		unset words[$last]

		last=$(( $last - 1 ))

	fi



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

		module=${words[$last]}

		# some traces format is "(%pS)", which like "(foo+0x0/0x1 [bar])"
@@ -313,9 +325,9 @@ handle_line() { 
	# Add up the line number to the symbol

	if [[ -z ${module} ]]

	then

		echo "${words[@]}" "$symbol"

		echo "${words[@]}" "$symbol ${info_str}"

	else

		echo "${words[@]}" "$symbol $module"

		echo "${words[@]}" "$symbol $module ${info_str}"

	fi

}