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 C9776C77B72 for ; Wed, 12 Apr 2023 20:26:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230028AbjDLU0e (ORCPT ); Wed, 12 Apr 2023 16:26:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229762AbjDLU0Y (ORCPT ); Wed, 12 Apr 2023 16:26:24 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89FE410DC for ; Wed, 12 Apr 2023 13:26:23 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 1EC2F631DF for ; Wed, 12 Apr 2023 20:26:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C79FC433A4; Wed, 12 Apr 2023 20:26:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681331182; bh=zo0BxAzMtQYruLjF5XaJiSkqwASG0OADnk73jUKYYMU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pGh8C+WjFDMkawFcUIWtEsUhPrhmYCi0exlZBJVzag/j57IfTMGMCHT/uSH6nBnO/ qY69xO3WOk/r1W/nY7ZPEMpmuOI6hdpqLNYRfGc4Gj51zroYfmHeyncccCPbuV3bTM 0ceZjyKGyOgzw1dXPXsNfavYYygL09hqrvNouTDMbuQ0q9pKNSiMRr9n9jo2Z1xdvb vsUql2XbzlSbef8FR2Oigx6di1bi7E53UAcfZ+7YnudmAoB5FijOwKYUnwaRJksD0w 8zAkeBSFe9ptgTiK7hq96ZWzV93WtNPGAB0vfBVLs1xXjziMbouEqxrvD9IssoC4VO 3HpR7NIvLXa8A== From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Miroslav Benes Subject: [PATCH 3/3] objtool: Generate ORC data for __pfx code Date: Wed, 12 Apr 2023 13:26:15 -0700 Message-Id: X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Allow unwinding from prefix code by copying the CFI from the starting instruction of the corresponding function. Even when the NOPs are replaced, they're still stack-invariant instructions so the same ORC entry can be reused everywhere. Signed-off-by: Josh Poimboeuf --- tools/objtool/check.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 2f3136145b2e..3f27a0278bf8 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -4123,6 +4123,7 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio static int add_prefix_symbol(struct objtool_file *file, struct symbol *func) { struct instruction *insn, *prev; + struct cfi_state *cfi; insn = find_insn(file, func->sec, func->offset); if (!insn) @@ -4151,6 +4152,19 @@ static int add_prefix_symbol(struct objtool_file *file, struct symbol *func) if (!prev) return -1; + if (!insn->cfi) { + /* + * This can happen if stack validation isn't enabled or the + * function is annotated with STACK_FRAME_NON_STANDARD. + */ + return 0; + } + + /* Propagate insn->cfi to the prefix code */ + cfi = cfi_hash_find_or_add(insn->cfi); + for (; prev != insn; prev = next_insn_same_sec(file, prev)) + prev->cfi = cfi; + return 0; } @@ -4158,7 +4172,7 @@ static int add_prefix_symbols(struct objtool_file *file) { struct section *sec; struct symbol *func; - int ret, warnings = 0; + int warnings = 0; for_each_sec(file, sec) { if (!(sec->sh.sh_flags & SHF_EXECINSTR)) -- 2.39.2