objtool/klp: Test rejection of a file-local static branch key

2026-09-21T09:12:07+00:00

A static branch key owned by a module cannot be reached with a klp reloc: late module patching allows the livepatch module to load first, leaving the __jump_table entry unresolved for jump_label_add_module() to dereference. validate_special_section_klp_reloc() rejects it at build time. test-jump-label-module-key covers that for a global key. A file-local one takes a different route to the same check: the compiler references a static through its section symbol plus an addend, so the key has to be resolved from the section before it can be recognised as STT_OBJECT at all. Until commit f9fb44b0ecef ("objtool/klp: Fix detection of corrupt static branch/call entries") it was not, and the reference was silently emitted. Give the fixture a STATIC_KEY knob and cover it. The test checks that the input really does reference the key through its section, since without that it is only a second copy of the existing test. Verified by reverting commit f9fb44b0ecef ("objtool/klp: Fix detection of corrupt static branch/call entries"): klp diff accepts the input and the test fails, under both gcc and clang. Assisted-by: Claude:claude-opus-4 Based-on-test-by: Joe Lawrence Assisted-by: Claude:claude-opus-5 Signed-off-by: Song Liu Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20260916184351.2720310-44-song@kernel.org

linux-next.git/tools/objtool/tests/generic/test-jump-label-module-static-key.sh, branch master

objtool/klp: Test rejection of a file-local static branch key