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 4E2D4C433EF for ; Thu, 14 Apr 2022 17:00:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242655AbiDNRDB (ORCPT ); Thu, 14 Apr 2022 13:03:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241739AbiDNRCO (ORCPT ); Thu, 14 Apr 2022 13:02:14 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79D1BF9546 for ; Thu, 14 Apr 2022 09:36:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=4X+Jq1i8p1Zvr7xXgePsT13L/w0211RpRgQvinilEoU=; b=ixL+7Ua9Xbp8XciRqWrCDg1iLL DUVWPGpnNP9uiPaABHJAOWuXQYanOJUEG4uMJ+Lcyk00lTlcVvQb1LYfkJFQMku2pCoiNVJItwatL hHdXbL96u/agQihpdkz/NDSbHTqKgu634M0Estw0JaYG+r/PZCuosn8h06/E8YN3GJBkYZwjSwPJI 0wJyOurYrF7rvtenvsLNV1wIGNnBTYRUlNmp+NVu6PGB2U0bqFZQ6c/A7VS3Im7txF/GnSa4yOYZL 2W1aj+KVdAPdQnTxoeholZ6TxMJm0HN9vWirmh09HtR91owJDRlhmGVInohuvBvdtOYkjy3CVntk/ F53M07sw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nf2Sj-00545G-Io; Thu, 14 Apr 2022 16:36:53 +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 4F5AD30031E; Thu, 14 Apr 2022 18:36:51 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 2943C32321547; Thu, 14 Apr 2022 18:36:51 +0200 (CEST) Date: Thu, 14 Apr 2022 18:36:51 +0200 From: Peter Zijlstra To: Josh Poimboeuf Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Miroslav Benes Subject: Re: [PATCH 02/18] objtool: Support data symbol printing Message-ID: References: <097057f88605aa67b0e3ec573fcf394ae7ac4d6f.1649891421.git.jpoimboe@redhat.com> <20220414152148.cwdefx744kymqcut@treble> <20220414153854.rqkt465xn4vzndr7@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220414153854.rqkt465xn4vzndr7@treble> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 14, 2022 at 08:38:54AM -0700, Josh Poimboeuf wrote: > > Yes, I'd not seen that yet, what's that for? The Changelog alludes to > > something, but I don't think it actually does get used later. > > Nick had asked for something like that, it's just a way to avoid doing > math every time we look at a warning, i.e. to convert func+offset to > sec+offset. > > But it's kind of ugly and I'm not 100% happy with it. > > Maybe it should be behind an option (--sec-offsets)? Can do I suppose... Myself, I have this script: $ cat objdump-func.sh #!/bin/bash OBJ=$1; shift FUNC=$1; shift objdump -wdr $@ $OBJ | awk "/^\$/ { P=0; } /$FUNC[^>]*>:\$/ { P=1; O=strtonum(\"0x\" \$1); } { if (P) { o=strtonum(\"0x\" \$1); printf(\"%04x \", o-O); print \$0; } }" That prints a symbol relative offset next to the section, something like: $ ./objdump-func.sh defconfig-build/vmlinux.o pick_next_task_idle 0000 00000000000a9eb0 : 0000 a9eb0: 41 54 push %r12 0002 a9eb2: 4c 8b a7 28 09 00 00 mov 0x928(%rdi),%r12 0009 a9eb9: 53 push %rbx 000a a9eba: 48 89 fb mov %rdi,%rbx 000d a9ebd: 66 90 xchg %ax,%ax 000f a9ebf: 66 90 xchg %ax,%ax 0011 a9ec1: 4c 89 e0 mov %r12,%rax 0014 a9ec4: 5b pop %rbx 0015 a9ec5: 41 5c pop %r12 0017 a9ec7: c3 ret 0018 a9ec8: e8 00 00 00 00 call a9ecd a9ec9: R_X86_64_PLT32 __update_idle_core-0x4 001d a9ecd: eb f0 jmp a9ebf 001f a9ecf: 4c 89 e0 mov %r12,%rax 0022 a9ed2: 83 83 b8 0b 00 00 01 addl $0x1,0xbb8(%rbx) 0029 a9ed9: 5b pop %rbx 002a a9eda: 41 5c pop %r12 002c a9edc: c3 ret 002d a9edd: 0f 1f 00 nopl (%rax)