klp-build fixes the input patches before building the patched kernel: it combines them into a single patch against the original source and adds #line directives, so that unchanged functions further down a patched file keep their __LINE__ values. This only happens after the original kernel has been built, so seeing the result, or testing this step, takes a full kernel build and --keep-tmp.
Add a --patch-only option which validates and fixes the patches, prints the fixed patch to stdout, and exits without building. It skips the .config checks and the kernel version setup, which only matter for building, so the tree it runs in doesn't need to be configured. It uses a private tmp dir rather than klp-tmp, which may hold a previous build that a later --short-circuit run wants to reuse. Assisted-by: Claude:claude-opus-5 Signed-off-by: Song Liu <[email protected]> --- scripts/livepatch/klp-build | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build index 6cdc36e97c21..295fad62d7b8 100755 --- a/scripts/livepatch/klp-build +++ b/scripts/livepatch/klp-build @@ -19,7 +19,7 @@ set -o nounset # This helps keep execution in pipes so pipefail+ERR trap can catch errors. shopt -s lastpipe -unset DEBUG_CLONE DIFF_CHECKSUM SKIP_CLEANUP VERBOSE XTRACE +unset DEBUG_CLONE DIFF_CHECKSUM PATCH_ONLY SKIP_CLEANUP VERBOSE XTRACE REPLACE=1 SHORT_CIRCUIT=0 @@ -137,6 +137,7 @@ Options: Advanced Options: -d, --debug Show symbol/reloc cloning decisions + --patch-only Print the fixed patch(es) and exit without building -S, --short-circuit=STEP Start at build step (requires prior --keep-tmp) 1|orig Build original kernel (default) 2|patched Build patched kernel @@ -160,7 +161,7 @@ process_args() { local patch short="hfj:o:vdS:T" - long="help,show-first-changed,jobs:,output:,no-replace,verbose,debug,short-circuit:,keep-tmp" + long="help,show-first-changed,jobs:,output:,no-replace,verbose,debug,patch-only,short-circuit:,keep-tmp" args=$(getopt --options "$short" --longoptions "$long" -- "$@") || { echo; usage; exit @@ -202,6 +203,10 @@ process_args() { keep_tmp=1 shift ;; + --patch-only) + PATCH_ONLY=1 + shift + ;; -S | --short-circuit) [[ ! -d "$TMP_DIR" ]] && die "--short-circuit requires preserved klp-tmp dir" keep_tmp=1 @@ -238,6 +243,15 @@ process_args() { KEEP_TMP="$keep_tmp" PATCHES=("$@") + if [[ -v PATCH_ONLY ]]; then + (( SHORT_CIRCUIT > 0 )) && die "--patch-only can't be used with --short-circuit" + + # Leave klp-tmp alone, it may hold a previous build + TMP_DIR="$(mktemp -d)" + PATCH_TMP_DIR="$TMP_DIR/tmp" + KEEP_TMP=0 + fi + for patch in "${PATCHES[@]}"; do [[ -f "$patch" ]] || die "$patch doesn't exist" done @@ -462,6 +476,9 @@ do_init() { [[ -x "$FIX_PATCH_LINES" ]] || die "can't find fix-patch-lines" command -v recountdiff &>/dev/null || die "recountdiff not found (install patchutils)" + # The rest is only needed for building + [[ -v PATCH_ONLY ]] && return 0 + validate_config set_module_name set_kernelversion @@ -910,6 +927,13 @@ build_patch_module() { process_args "$@" do_init +if [[ -v PATCH_ONLY ]]; then + validate_patches + fix_patches + cat "${PATCHES[@]}" + exit 0 +fi + if (( SHORT_CIRCUIT <= 2 )); then status "Validating patch(es)" validate_patches -- 2.53.0-Meta
