From d322f6a24ee5964a58294f61bf96a1b6404c676d Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Mon, 8 Sep 2025 17:41:57 +0200 Subject: scripts/decode_stacktrace.sh: symbol: avoid trailing whitespaces A few patches slightly improving the output generated by decode_stacktrace.sh. This patch (of 3): Lines having a symbol to decode might not always have info after this symbol. It means ${info_str} might not be set, but it will always be printed after a space, causing trailing whitespaces. That's a detail, but when the output is opened with an editor marking these trailing whitespaces, that's a bit disturbing. It is easy to remove them by printing this variable with a space only if it is set. While at it, do the same with ${module} and print everything in one line. Link: https://lkml.kernel.org/r/20250908-decode_strace_indent-v1-0-28e5e4758080@kernel.org Link: https://lkml.kernel.org/r/20250908-decode_strace_indent-v1-1-28e5e4758080@kernel.org Signed-off-by: Matthieu Baerts (NGI0) Reviewed-by: Carlos Llamas Reviewed-by: Breno Leitao Reviewed-by: Luca Ceresoli Cc: Carlos Llamas Cc: Elliot Berman Cc: Stephen Boyd Signed-off-by: Andrew Morton --- scripts/decode_stacktrace.sh | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'scripts/decode_stacktrace.sh') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index 17abc4e7a985..c6b5c14412f0 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -323,12 +323,7 @@ handle_line() { parse_symbol # modifies $symbol # Add up the line number to the symbol - if [[ -z ${module} ]] - then - echo "${words[@]}" "$symbol ${info_str}" - else - echo "${words[@]}" "$symbol $module ${info_str}" - fi + echo "${words[@]}" "${symbol}${module:+ ${module}}${info_str:+ ${info_str}}" } while read line; do -- cgit From 4a2fc4897b5e0ca1e7a3cb4e32f44c7db3367dee Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Mon, 8 Sep 2025 17:41:58 +0200 Subject: scripts/decode_stacktrace.sh: symbol: preserve alignment With lines having a symbol to decode, the script was only trying to preserve the alignment for the timestamps, but not the rest, nor when the caller was set (CONFIG_PRINTK_CALLER=y). With this sample ... [ 52.080924] Call Trace: [ 52.080926] [ 52.080931] dump_stack_lvl+0x6f/0xb0 ... the script was producing the following output: [ 52.080924] Call Trace: [ 52.080926] [ 52.080931] dump_stack_lvl (arch/x86/include/asm/irqflags.h:19) (dump_stack_lvl is no longer aligned with : one missing space) With this other sample ... [ 52.080924][ T48] Call Trace: [ 52.080926][ T48] [ 52.080931][ T48] dump_stack_lvl+0x6f/0xb0 ... the script was producing the following output: [ 52.080924][ T48] Call Trace: [ 52.080926][ T48] [ 52.080931][ T48] dump_stack_lvl (arch/x86/include/asm/irqflags.h:19) (the misalignment is clearer here) That's because the script had a workaround for CONFIG_PRINTK_TIME=y only, see the previous comment called "Format timestamps with tabs". To always preserve spaces, they need to be recorded along the words. That is what is now done with the new 'spaces' array. Some notes: - 'extglob' is needed only for this operation, and that's why it is set in a dedicated subshell. - 'read' is used with '-r' not to treat a character in any special way, e.g. when followed by a space. - When a word is removed from the 'words' array, the corresponding space needs to be removed from the 'spaces' array as well. With the last sample, we now have: [ 52.080924][ T48] Call Trace: [ 52.080926][ T48] [ 52.080931][ T48] dump_stack_lvl (arch/x86/include/asm/irqflags.h:19) (the alignment is preserved) Link: https://lkml.kernel.org/r/20250908-decode_strace_indent-v1-2-28e5e4758080@kernel.org Signed-off-by: Matthieu Baerts (NGI0) Tested-by: Carlos Llamas Cc: Breno Leitao Cc: Elliot Berman Cc: Luca Ceresoli Cc: Stephen Boyd Signed-off-by: Andrew Morton --- scripts/decode_stacktrace.sh | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) (limited to 'scripts/decode_stacktrace.sh') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index c6b5c14412f0..0c92d6a7f777 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -255,10 +255,11 @@ handle_line() { basepath=${basepath%/init/main.c:*)} fi - local words + local words spaces - # Tokenize - read -a words <<<"$1" + # Tokenize: words and spaces to preserve the alignment + read -ra words <<<"$1" + IFS='#' read -ra spaces <<<"$(shopt -s extglob; echo "${1//+([^[:space:]])/#}")" # Remove hex numbers. Do it ourselves until it happens in the # kernel @@ -270,19 +271,13 @@ handle_line() { for i in "${!words[@]}"; do # Remove the address if [[ ${words[$i]} =~ \[\<([^]]+)\>\] ]]; then - unset words[$i] - fi - - # Format timestamps with tabs - if [[ ${words[$i]} == \[ && ${words[$i+1]} == *\] ]]; then - unset words[$i] - words[$i+1]=$(printf "[%13s\n" "${words[$i+1]}") + unset words[$i] spaces[$i] fi done if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then words[$last-1]="${words[$last-1]} ${words[$last]}" - unset words[$last] + unset words[$last] spaces[$last] last=$(( $last - 1 )) fi @@ -294,7 +289,7 @@ handle_line() { local info_str="" if [[ ${words[$last]} =~ \([A-Z]*\) ]]; then info_str=${words[$last]} - unset words[$last] + unset words[$last] spaces[$last] last=$(( $last - 1 )) fi @@ -311,7 +306,7 @@ handle_line() { modbuildid= fi symbol=${words[$last-1]} - unset words[$last-1] + unset words[$last-1] spaces[$last-1] else # The symbol is the last element, process it symbol=${words[$last]} @@ -323,7 +318,10 @@ handle_line() { parse_symbol # modifies $symbol # Add up the line number to the symbol - echo "${words[@]}" "${symbol}${module:+ ${module}}${info_str:+ ${info_str}}" + for i in "${!words[@]}"; do + echo -n "${spaces[i]}${words[i]}" + done + echo "${spaces[$last]}${symbol}${module:+ ${module}}${info_str:+ ${info_str}}" } while read line; do -- cgit From e1831e8dd1c839088692c09c97031ce467db1a2a Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Mon, 8 Sep 2025 17:41:59 +0200 Subject: scripts/decode_stacktrace.sh: code: preserve alignment With lines having a code to decode, the alignment was not preserved for the first line. With this sample ... [ 52.238089][ T55] RIP: 0010:__ip_queue_xmit+0x127c/0x1820 [ 52.238401][ T55] Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 (...) ... the script was producing the following output: [ 52.238089][ T55] RIP: 0010:__ip_queue_xmit (...) [ 52.238401][ T55] Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 (...) That's because scripts/decodecode doesn't preserve the alignment. No need to modify it, it is enough to give only the "Code: (...)" part to this script, and print the prefix without modifications. With the same sample, we now have: [ 52.238089][ T55] RIP: 0010:__ip_queue_xmit (...) [ 52.238401][ T55] Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 (...) Link: https://lkml.kernel.org/r/20250908-decode_strace_indent-v1-3-28e5e4758080@kernel.org Signed-off-by: Matthieu Baerts (NGI0) Tested-by: Carlos Llamas Cc: Breno Leitao Cc: Elliot Berman Cc: Luca Ceresoli Cc: Stephen Boyd Signed-off-by: Andrew Morton --- scripts/decode_stacktrace.sh | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'scripts/decode_stacktrace.sh') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index 0c92d6a7f777..c73cb802a0a3 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -242,8 +242,10 @@ debuginfod_get_vmlinux() { decode_code() { local scripts=`dirname "${BASH_SOURCE[0]}"` + local lim="Code: " - echo "$1" | $scripts/decodecode + echo -n "${1%%${lim}*}" + echo "${lim}${1##*${lim}}" | $scripts/decodecode } handle_line() { -- cgit From 7d9f7d390f6af3a29614e81e802e2b9c238eb7b2 Mon Sep 17 00:00:00 2001 From: Carlos Llamas Date: Thu, 30 Oct 2025 01:03:33 +0000 Subject: scripts/decode_stacktrace.sh: fix build ID and PC source parsing Support for parsing PC source info in stacktraces (e.g. '(P)') was added in commit 2bff77c665ed ("scripts/decode_stacktrace.sh: fix decoding of lines with an additional info"). However, this logic was placed after the build ID processing. This incorrect order fails to parse lines containing both elements, e.g.: drm_gem_mmap_obj+0x114/0x200 [drm 03d0564e0529947d67bb2008c3548be77279fd27] (P) This patch fixes the problem by extracting the PC source info first and then processing the module build ID. With this change, the line above is now properly parsed as such: drm_gem_mmap_obj (./include/linux/mmap_lock.h:212 ./include/linux/mm.h:811 drivers/gpu/drm/drm_gem.c:1177) drm (P) While here, also add a brief explanation the build ID section. Link: https://lkml.kernel.org/r/20251030010347.2731925-1-cmllamas@google.com Fixes: 2bff77c665ed ("scripts/decode_stacktrace.sh: fix decoding of lines with an additional info") Signed-off-by: Carlos Llamas Reviewed-by: Matthieu Baerts (NGI0) Reviewed-by: Luca Ceresoli Cc: Breno Leitao Cc: Catalin Marinas Cc: Marc Rutland Cc: Mark Brown Cc: Matthieu Baerts Cc: Miroslav Benes Cc: Puranjay Mohan Cc: Signed-off-by: Andrew Morton --- scripts/decode_stacktrace.sh | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'scripts/decode_stacktrace.sh') diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index c73cb802a0a3..8d01b741de62 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -277,12 +277,6 @@ handle_line() { fi done - if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then - words[$last-1]="${words[$last-1]} ${words[$last]}" - unset words[$last] spaces[$last] - last=$(( $last - 1 )) - fi - # Extract info after the symbol if present. E.g.: # func_name+0x54/0x80 (P) # ^^^ @@ -295,6 +289,14 @@ handle_line() { last=$(( $last - 1 )) fi + # Join module name with its build id if present, as these were + # split during tokenization (e.g. "[module" and "modbuildid]"). + if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then + words[$last-1]="${words[$last-1]} ${words[$last]}" + unset words[$last] spaces[$last] + last=$(( $last - 1 )) + fi + if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then module=${words[$last]} # some traces format is "(%pS)", which like "(foo+0x0/0x1 [bar])" -- cgit