Merge tag 'objtool-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

- Add unit test suite for objtool klp functionality and
known

Merge tag 'objtool-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

- Add unit test suite for objtool klp functionality and
known failure modes (by Song Liu and Puranjay Mohan,
with fixes by Joe Lawrence)

* tag 'objtool-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
objtool/klp: Add test for ThinLTO symbols sharing a demangled name
objtool/klp: Add test for Clang switch jump tables
objtool/klp: Add test for UBSAN metadata in an unchanged function
objtool/klp: Add test for absolute and __ADDRESSABLE symbols
objtool/klp: Add test for a patch which strips a data annotation
objtool/klp: Add test for the alignment of cloned data sections
objtool/klp: Add test for alternative replacement code in checksums
objtool/klp: Add test for instruction operand checksums
objtool/klp: Add test for a static call introduced by the patch
objtool/klp: Add test for tracepoint and pr_debug static branch keys
objtool/klp: Add test for a static branch introduced by the patch
objtool/klp: Add test for symbols with no checksum entry of their own
objtool/klp: Add test for data object checksums
objtool/klp: Test text annotations on alternative replacements
objtool/klp: Test a hand-built livepatch module's static call keys
objtool/klp: Test rejection of a file-local static branch key
objtool/klp: Add test for symbols whose linkage the patch changes
objtool/klp: Add test for kCFI prefix symbols and traps
objtool/klp: Add test for __bug_table, __ex_table and __mcount_loc extraction
objtool/klp: Add test for static locals which must not be correlated
...

show more ...

objtool/klp: Add test for correlation across ThinLTO name mangling

ThinLTO promotes the file-local symbols an imported function touches,
renaming them name.llvm.<hash>. The hash is content derived,

objtool/klp: Add test for correlation across ThinLTO name mangling

ThinLTO promotes the file-local symbols an imported function touches,
renaming them name.llvm.<hash>. The hash is content derived, so it changes
whenever the module does:

original: counter.llvm.13663304415433785070
patched: counter.llvm.10543383937958011340

Correlating the two objects therefore requires demangling the suffix;
matching raw names would see two unrelated symbols and treat the variable
as new.

The resulting klp relocation also has to name the original symbol, since
that is the one in the running kernel's kallsyms. Naming the patched
build's symbol produces a relocation which can never be resolved.

ThinLTO is a clang feature, so the test declares itself clang-only. It
also needs an lld from the same LLVM release as $CC; a mismatched pair
fails with "Invalid summary version", which reads like a broken test rather
than a broken environment, so probe for a working lld and skip if there is
none.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Assisted-by: Claude:claude-opus-5
Link: https://patch.msgid.link/20260916184351.2720310-25-song@kernel.org

show more ...