[PATCH 37/48] objtool/klp: Remove "objtool --checksum"

Josh Poimboeuf
2026-04-23T04:04:42Z

The checksum functionality has been moved to "objtool klp checksum"
which is now used by klp-build. Remove the now-dead --checksum and
--debug-checksum options from the default objtool command.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
scripts/livepatch/klp-build | 3 +++
tools/objtool/builtin-check.c | 17 +----------------
tools/objtool/check.c | 10 ----------
3 files changed, 4 insertions(+), 26 deletions(-)

diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build
index d29ef3022556..eda690b297cc 100755
--- a/scripts/livepatch/klp-build
+++ b/scripts/livepatch/klp-build
@@ -277,6 +277,9 @@ validate_config() {
[[ "$CONFIG_AS_VERSION" -lt 200000 ]] && \
die "Clang assembler version < 20 not supported"

+ "$SRC/tools/objtool/objtool" klp 2>&1 | command grep -q "not implemented" && \
+ die "objtool not built with KLP support; install xxhash-devel/libxxhash-dev (version >= 0.8) and recompile"
+
return 0
}

diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index b780df513715..ec7f10a5ef19 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -73,7 +73,6 @@ static int parse_hacks(const struct option *opt, const char *str, int unset)

static const struct option check_options[] = {
OPT_GROUP("Actions:"),
- OPT_BOOLEAN(0, "checksum", &opts.checksum, "generate per-function checksums"),
OPT_BOOLEAN(0, "cfi", &opts.cfi, "annotate kernel control flow integrity (kCFI) function preambles"),
OPT_STRING_OPTARG('d', "disas", &opts.disas, "function-pattern", "disassemble functions", "*"),
OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr,skylake", "patch toolchain bugs/limitations", parse_hacks),
@@ -95,7 +94,6 @@ static const struct option check_options[] = {
OPT_GROUP("Options:"),
OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"),
OPT_BOOLEAN(0, "backup", &opts.backup, "create backup (.orig) file on warning/error"),
- OPT_STRING(0, "debug-checksum", &opts.debug_checksum, "funcs", "enable checksum debug output"),
OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"),
OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"),
OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"),
@@ -165,20 +163,7 @@ static bool opts_valid(void)
return false;
}

-#ifndef BUILD_KLP
- if (opts.checksum) {
- ERROR("--checksum not supported; install xxhash-devel/libxxhash-dev (version >= 0.8) and recompile");
- return false;
- }
-#endif
-
- if (opts.debug_checksum && !opts.checksum) {
- ERROR("--debug-checksum requires --checksum");
- return false;
- }
-
- if (opts.checksum ||
- opts.disas ||
+ if (opts.disas ||
opts.hack_jump_label ||
opts.hack_noinstr ||
opts.ibt ||
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 3e5d335d0e29..ae047be919c5 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -18,7 +18,6 @@
#include <objtool/special.h>
#include <objtool/trace.h>
#include <objtool/warn.h>
-#include <objtool/checksum.h>
#include <objtool/util.h>

#include <linux/objtool_types.h>
@@ -4946,15 +4945,6 @@ int check(struct objtool_file *file)
if (opts.noabs)
warnings += check_abs_references(file);

- if (opts.checksum) {
- ret = calculate_checksums(file);
- if (ret)
- goto out;
- ret = create_sym_checksum_section(file);
- if (ret)
- goto out;
- }
-
if (opts.orc && nr_insns) {
ret = orc_create(file);
if (ret)
--
2.53.0