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
...

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objtool/klp: Add test for tracepoint and pr_debug static branch keys

A module-owned static branch key is normally fatal, because late module
patching lets the livepatch load before the module it dep

objtool/klp: Add test for tracepoint and pr_debug static branch keys

A module-owned static branch key is normally fatal, because late module
patching lets the livepatch load before the module it depends on and
jump_label_add_module() then dereferences an unresolved entry.

Tracepoints and pr_debug() generate such keys everywhere, so refusing them
outright would make any function containing a trace_*() call or a
pr_debug() unpatchable. klp diff drops the entry, warns, and carries on:
the patched code works with that one tracepoint or debug print permanently
off.

Both halves matter, and the test asserts both. A build which fails is a
function nobody can patch; an entry left in place is the corruption the
rejection exists to prevent.

Give the fixture a KEY_NAME knob so the same static branch can be built
with either special name. Verified by removing each exemption in turn --
the test fails for both. That the entry is then dropped is asserted but
not isolated, and the test says so.

Assisted-by: Claude:claude-opus-4
Based-on-test-by: Joe Lawrence <joe.lawrence@redhat.com>
Assisted-by: Claude:claude-opus-5
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20260916184351.2720310-50-song@kernel.org

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