The following commit has been merged into the objtool/urgent branch of tip:
Commit-ID: a8ff29f0ca1d63a215ef445102662850a912d127
Gitweb: https://git.kernel.org/tip/a8ff29f0ca1d63a215ef445102662850a912d127
Author: Josh Poimboeuf <jpoimboe@kernel.org>
AuthorDate: Tue, 27 Jan 2026 17:12:05 -08:00
Committer: Josh Poimboeuf <jpoimboe@kernel.org>
CommitterDate: Thu, 29 Jan 2026 10:09:26 -08:00
livepatch/klp-build: Require Clang assembler >= 20
Some special sections specify their ELF section entsize, for example:
.pushsection section, "M", @progbits, 8
The entsize (8 in this example) is needed by objtool klp-diff for
extracting individual entries.
Clang assembler versions older than 20 silently ignore the above
construct and set entsize to 0, resulting in the following error:
.discard.annotate_data: missing special section entsize or annotations
Add a klp-build check to prevent the use of Clang assembler versions
prior to 20.
Fixes: 24ebfcd65a87 ("livepatch/klp-build: Introduce klp-build script for generating livepatch modules")
Reported-by: Song Liu <song@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/957fd52e375d0e2cfa3ac729160da995084a7f5e.1769562556.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
scripts/livepatch/klp-build | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build
index a73515a..809e198 100755
--- a/scripts/livepatch/klp-build
+++ b/scripts/livepatch/klp-build
@@ -249,6 +249,10 @@ validate_config() {
[[ -v CONFIG_GCC_PLUGIN_RANDSTRUCT ]] && \
die "kernel option 'CONFIG_GCC_PLUGIN_RANDSTRUCT' not supported"
+ [[ -v CONFIG_AS_IS_LLVM ]] && \
+ [[ "$CONFIG_AS_VERSION" -lt 200000 ]] && \
+ die "Clang assembler version < 20 not supported"
+
return 0
}