objtool/klp: Fix false module dependencies caused by dead relocs

When creating a klp reloc, klp-diff keeps the original relocation but
converts the referenced symbol to an UNDEF/WEAK placeholder tombstone
symbol, which gets fully disabled later by klp post-link.  The tombstone
symbol is only needed to avoid confusing objtool when it does the final
run on the patch module.

However, for references to exported symbols, modpost sees the reference
to the tombstone symbol as a real reference to an exported symbol,
resulting in a false module dependency getting created.

Further, for a reference to a tombstone symbol which is exported into a
module namespace, e.g. via EXPORT_SYMBOL_FOR_KVM_INTERNAL(), modpost
can't satisfy the dependency, resulting in a warning like the following:

  module ... uses symbol kvm_flush_remote_tlbs from namespace
  module:kvm-amd,kvm-intel, but does not import it.

Rename the placeholder tombstone symbols to ".klp.tombstone.<name>" so
modpost no longer recognizes them.

Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Reported-by: Ben Procknow <bprockno@redhat.com>
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: live-patching@vger.kernel.org
Link: https://lore.kernel.org/20260720145658.1103243-5-joe.lawrence@redhat.com
Link: https://patch.msgid.link/9548393f4d89ec3b498f4f69aa6ef6b9bb7150fe.1785727106.git.jpoimboe@kernel.org

0 files changed, 0 insertions, 0 deletions