From ba77fe55781a2464f68b6c13b4b31d05abd2abcf Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 10 Apr 2026 21:49:56 -0700 Subject: klp-build: Fix checksum comparison for changed offsets The klp-build -f/--show-first-changed feature uses diff to compare checksum log lines between original and patched objects. However, diff compares entire lines, including the offset field. When a function is at a different section offset, the offset field differs even though the instruction checksum is identical, causing the wrong instruction to be printed. Only compare the checksum field when looking for the first changed instruction. Also print both the original and patched offsets when they differ. Fixes: 78be9facfb5e ("livepatch/klp-build: Add --show-first-changed option to show function divergence") Acked-by: Song Liu Signed-off-by: Josh Poimboeuf --- scripts/livepatch/klp-build | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) (limited to 'scripts/livepatch') diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build index e19d93b78fcb..8f0ea56f2640 100755 --- a/scripts/livepatch/klp-build +++ b/scripts/livepatch/klp-build @@ -727,13 +727,29 @@ diff_checksums() { ) for func in ${funcs[$file]}; do - diff <( grep0 -E "^DEBUG: .*checksum: $func " "$orig_log" | sed "s|$ORIG_DIR/||") \ - <( grep0 -E "^DEBUG: .*checksum: $func " "$patched_log" | sed "s|$PATCHED_DIR/||") \ - | gawk '/^< DEBUG: / { - gsub(/:/, "") - printf "%s: %s: %s\n", $3, $5, $6 - exit - }' || true + local -a orig patched + paste <(grep0 -E "^DEBUG: .*checksum: $func " "$orig_log") \ + <(grep0 -E "^DEBUG: .*checksum: $func " "$patched_log") | + while IFS= read -r line; do + read -ra orig <<< "${line%%$'\t'*}" + read -ra patched <<< "${line#*$'\t'}" + + if [[ ${#patched[@]} -eq 0 ]]; then + printf "%s: %s: %s (removed)\n" "${orig[1]%:}" "${orig[3]}" "${orig[-2]}" + break + elif [[ ${#orig[@]} -eq 0 ]]; then + printf "%s: %s: %s (added)\n" "${patched[1]%:}" "${patched[3]}" "${patched[-2]}" + break + fi + + [[ "${orig[-1]}" == "${patched[-1]}" ]] && continue + + printf "%s: %s: %s" "${orig[1]%:}" "${orig[3]}" "${orig[-2]}" + [[ "${orig[-2]}" != "${patched[-2]}" ]] && \ + printf " (patched: %s)" "${patched[-2]}" + printf "\n" + break + done || true done done } -- cgit v1.2.3