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    Subject[PATCH 5.15 31/89] objtool: skip non-text sections when adding return-thunk sites
    Date
    From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

    The .discard.text section is added in order to reserve BRK, with a
    temporary function just so it can give it a size. This adds a relocation to
    the return thunk, which objtool will add to the .return_sites section.
    Linking will then fail as there are references to the .discard.text
    section.

    Do not add instructions from non-text sections to the list of return thunk
    calls, avoiding the reference to .discard.text.

    Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
    Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    tools/objtool/check.c | 4 +++-
    1 file changed, 3 insertions(+), 1 deletion(-)

    --- a/tools/objtool/check.c
    +++ b/tools/objtool/check.c
    @@ -1153,7 +1153,9 @@ static void add_return_call(struct objto
    insn->type = INSN_RETURN;
    insn->retpoline_safe = true;

    - list_add_tail(&insn->call_node, &file->return_thunk_list);
    + /* Skip the non-text sections, specially .discard ones */
    + if (insn->sec->text)
    + list_add_tail(&insn->call_node, &file->return_thunk_list);
    }

    /*

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