From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A058C43334 for ; Tue, 12 Jul 2022 19:00:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235103AbiGLTAZ (ORCPT ); Tue, 12 Jul 2022 15:00:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235147AbiGLS7K (ORCPT ); Tue, 12 Jul 2022 14:59:10 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BBCEEEFF85; Tue, 12 Jul 2022 11:47:58 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1474DB81BBB; Tue, 12 Jul 2022 18:47:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6324AC3411C; Tue, 12 Jul 2022 18:47:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657651675; bh=kSgwTRsllFILj+qKMFsmLtIGbXkCDdd8/3UJkSJqtAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X5xmQIFykJ9jVkFNjBUoq2rrJZPSJlyRi6l63wy8PpCIOjXHtIilroBKG/gcwaXOx uqldTRHDq4HgN/1MeHR1xaI0rD4SmpFVrxAwSI3KXJppBB6aoYny7AOLn5hVJMHiIn 7EXlXIfZuJBvk8PQSQxXNtAKBFRpN1FggGXH4oLc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Peter Zijlstra (Intel)" , Josh Poimboeuf , Thadeu Lima de Souza Cascardo Subject: [PATCH 5.15 21/78] objtool: Default ignore INT3 for unreachable Date: Tue, 12 Jul 2022 20:38:51 +0200 Message-Id: <20220712183239.696980857@linuxfoundation.org> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220712183238.844813653@linuxfoundation.org> References: <20220712183238.844813653@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra commit 1ffbe4e935f9b7308615c75be990aec07464d1e7 upstream. Ignore all INT3 instructions for unreachable code warnings, similar to NOP. This allows using INT3 for various paddings instead of NOPs. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154317.343312938@infradead.org Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman --- tools/objtool/check.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2965,9 +2965,8 @@ static int validate_branch(struct objtoo switch (insn->type) { case INSN_RETURN: - if (next_insn && next_insn->type == INSN_TRAP) { - next_insn->ignore = true; - } else if (sls && !insn->retpoline_safe) { + if (sls && !insn->retpoline_safe && + next_insn && next_insn->type != INSN_TRAP) { WARN_FUNC("missing int3 after ret", insn->sec, insn->offset); } @@ -3014,9 +3013,8 @@ static int validate_branch(struct objtoo break; case INSN_JUMP_DYNAMIC: - if (next_insn && next_insn->type == INSN_TRAP) { - next_insn->ignore = true; - } else if (sls && !insn->retpoline_safe) { + if (sls && !insn->retpoline_safe && + next_insn && next_insn->type != INSN_TRAP) { WARN_FUNC("missing int3 after indirect jump", insn->sec, insn->offset); } @@ -3187,7 +3185,7 @@ static bool ignore_unreachable_insn(stru int i; struct instruction *prev_insn; - if (insn->ignore || insn->type == INSN_NOP) + if (insn->ignore || insn->type == INSN_NOP || insn->type == INSN_TRAP) return true; /*