[PATCH 23/48] klp-build: Fix patch cleanup on interrupt

Josh Poimboeuf
2026-04-23T04:04:35Z

If a build error occurs and the user hits Ctrl-C while a large patch is
being reverted during cleanup, the cleanup EXIT trap gets re-triggered
and tries to re-revert the already partially-reverted patch. That
causes 'patch -R' to repeatedly prompt

"Unreversed patch detected! Ignore -R? [n]"

for each already-reverted hunk, with no way to break out.

Fix it by adding '--force' to the patch revert command in
revert_patch(), which causes it to silently ignore already-reverted
hunks. And ignore errors, as the cleanup is always best-effort.

For similar reasons, add to APPLIED_PATCHES before (rather than after)
applying the patch in apply_patch() so an interrupted apply will also
get cleaned up.

Fixes: d36a7343f4ba ("livepatch/klp-build: switch to GNU patch and recountdiff")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
scripts/livepatch/klp-build | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build
index a7f571df7813..60231cf49e5c 100755
--- a/scripts/livepatch/klp-build
+++ b/scripts/livepatch/klp-build
@@ -384,15 +384,15 @@ apply_patch() {
warn "${patch} applied with fuzz"
fi

- patch -d "$SRC" -p1 --no-backup-if-mismatch -r /dev/null "${extra_args[@]}" --silent < "$patch"
APPLIED_PATCHES+=("$patch")
+ patch -d "$SRC" -p1 --no-backup-if-mismatch -r /dev/null "${extra_args[@]}" --silent < "$patch"
}

revert_patch() {
local patch="$1"
local tmp=()

- patch -d "$SRC" -p1 -R --silent --no-backup-if-mismatch -r /dev/null < "$patch"
+ patch -d "$SRC" -p1 -R --force --no-backup-if-mismatch -r /dev/null &> /dev/null < "$patch" || true

for p in "${APPLIED_PATCHES[@]}"; do
[[ "$p" == "$patch" ]] && continue
--
2.53.0