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 B0396C433EF for ; Tue, 8 Mar 2022 15:56:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235049AbiCHP5I (ORCPT ); Tue, 8 Mar 2022 10:57:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348041AbiCHP4E (ORCPT ); Tue, 8 Mar 2022 10:56:04 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0D154F9CD for ; Tue, 8 Mar 2022 07:55:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=iwGCnfXB3kwKpXZ2OxhUFUJdGuoD7mQ0N21yE4UJlcY=; b=gdZplKgAVvGkpPjjoOpbLc3mD7 eijW3uIpZJ6506Uzm5URs176gq+RqCIqOYQG0Q59ZUgP68pnW3HaAN1WEzvgnpnr/CxyMIegWM1uo U7b5ZWSiDfFvv3mu3y12QeC/+uMKcjgCdkmYeiU+dbMT0NWu7Te0ZB4ilVJKm4sahCsP5vXU4axUf E7OX1AOxKBjwmaWD6TQDUBxMTlmqQ3sf771fefEYQex1SrUbmuAhXW+e104KmTKsdCA17Xs223fhP pCU1vwuPmQ1aR2a4++B28G5cIhy5l/SBWOguq1QJxrbJzH/EwbI6/Qo7+T6FqGuURG/LUsSpvMztz jimxGV5w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nRcAb-00GIup-Fz; Tue, 08 Mar 2022 15:54:41 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D7C423003BC; Tue, 8 Mar 2022 16:54:38 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id BA3A12B55FFB7; Tue, 8 Mar 2022 16:54:38 +0100 (CET) Message-ID: <20220308154317.282720146@infradead.org> User-Agent: quilt/0.66 Date: Tue, 08 Mar 2022 16:30:13 +0100 From: Peter Zijlstra To: x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com, jpoimboe@redhat.com, andrew.cooper3@citrix.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, ndesaulniers@google.com, keescook@chromium.org, samitolvanen@google.com, mark.rutland@arm.com, alyssa.milburn@intel.com, mbenes@suse.cz, rostedt@goodmis.org, mhiramat@kernel.org, alexei.starovoitov@gmail.com Subject: [PATCH v4 02/45] objtool: Add --dry-run References: <20220308153011.021123062@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a --dry-run argument to skip writing the modifications. This is convenient for debugging. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook Reviewed-by: Miroslav Benes --- tools/objtool/builtin-check.c | 3 ++- tools/objtool/elf.c | 3 +++ tools/objtool/include/objtool/builtin.h | 2 +- 3 files changed, 6 insertions(+), 2 deletions(-) --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -20,7 +20,7 @@ #include bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, - validate_dup, vmlinux, mcount, noinstr, backup, sls; + validate_dup, vmlinux, mcount, noinstr, backup, sls, dryrun; static const char * const check_usage[] = { "objtool check [] file.o", @@ -46,6 +46,7 @@ const struct option check_options[] = { OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"), OPT_BOOLEAN('S', "sls", &sls, "validate straight-line-speculation"), + OPT_BOOLEAN(0, "dry-run", &dryrun, "don't write the modifications"), OPT_END(), }; --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -1019,6 +1019,9 @@ int elf_write(struct elf *elf) struct section *sec; Elf_Scn *s; + if (dryrun) + return 0; + /* Update changed relocation sections and section headers: */ list_for_each_entry(sec, &elf->sections, list) { if (sec->changed) { --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -9,7 +9,7 @@ extern const struct option check_options[]; extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, - validate_dup, vmlinux, mcount, noinstr, backup, sls; + validate_dup, vmlinux, mcount, noinstr, backup, sls, dryrun; extern int cmd_parse_options(int argc, const char **argv, const char * const usage[]);