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 CBF3BC433EF for ; Tue, 22 Mar 2022 13:51:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234134AbiCVNxH (ORCPT ); Tue, 22 Mar 2022 09:53:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235876AbiCVNwz (ORCPT ); Tue, 22 Mar 2022 09:52:55 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0EF9650B07; Tue, 22 Mar 2022 06:51:28 -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 sin.source.kernel.org (Postfix) with ESMTPS id 6D0CACE1E18; Tue, 22 Mar 2022 13:51:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 17D78C340EC; Tue, 22 Mar 2022 13:51:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647957084; bh=+PcSzqlfSr4quKABCcRJgSwsi7LZhav0meRk6eGzyQk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=FdatOK5EsCCKNSnd0SFBfhCB1ogmnUyN25HzjzgibJkE8MGgn40+e8L/IOlsBXcEJ HMrA0modxfnFK4pVridEsoQREyNK44MG/If1ZkUJh1d+8MYgKmupFlpE3rY//nXs0K ZvQ+DZfvR6W2vDeaCzZ9QCJqkTpRsj1ZqKBXFS8rxAu8MBIYQDsXEyGq7ssz3WENOU 8DSxM+7R10paiWeViNMFJbu5uU0Ulj0GswYgV+N4JJPnJBH+rf9AljCATLTAE9YUUX XiJMzjq03TNToclXEXlkhNm9G+E2juwvKLEPI0p4V6UnVnTPiCNz8d9K8EaVBRA6H4 SzRxDhwH0LBFQ== Date: Tue, 22 Mar 2022 22:51:18 +0900 From: Masami Hiramatsu To: Mark Rutland Cc: Peter Zijlstra , Stephen Rothwell , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Linux Kernel Mailing List , Linux Next Mailing List , rostedt@goodmis.org, ast@kernel.org, hjl.tools@gmail.com, rick.p.edgecombe@intel.com, rppt@kernel.org, linux-toolchains@vger.kernel.org, Andrew.Cooper3@citrix.com, ndesaulniers@google.com Subject: Re: linux-next: build warnings after merge of the tip tree Message-Id: <20220322225118.ec33bf93e19d40f27d73c8d1@kernel.org> In-Reply-To: References: <20220321140327.777f9554@canb.auug.org.au> <20220322143136.0e78366c3521b54b7b9385b8@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Tue, 22 Mar 2022 13:15:58 +0000 Mark Rutland wrote: > On Tue, Mar 22, 2022 at 02:31:36PM +0900, Masami Hiramatsu wrote: > > On Mon, 21 Mar 2022 17:48:54 +0100 > > Peter Zijlstra wrote: > > > > > On Mon, Mar 21, 2022 at 02:04:05PM +0100, Peter Zijlstra wrote: > > > > On Mon, Mar 21, 2022 at 01:55:49PM +0100, Peter Zijlstra wrote: > > > > > On Mon, Mar 21, 2022 at 02:03:27PM +1100, Stephen Rothwell wrote: > > > > > > Hi all, > > > > > > > > > > > > After merging the tip tree, today's linux-next build (x864 allmodconfig) > > > > > > produced these new warnings: > > > > > > > > > > > > vmlinux.o: warning: objtool: arch_rethook_prepare()+0x55: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: arch_rethook_trampoline_callback()+0x3e: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: unwind_next_frame()+0x93e: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: unwind_next_frame()+0x5f2: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: unwind_next_frame()+0x4a7: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: __rethook_find_ret_addr()+0x81: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: __rethook_find_ret_addr()+0x90: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: rethook_trampoline_handler()+0x8c: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > vmlinux.o: warning: objtool: rethook_trampoline_handler()+0x9b: relocation to !ENDBR: arch_rethook_trampoline+0x0 > > > > > > > > > > Hurmph, lemme go figure out where that code comes from, I've not seen > > > > > those. > > > > > > > > Ahh, something tracing. I'll go do some patches on top of it. > > > > > > The below gets rid of the objtool warnings. > > > > Yes, I confirmed that. > > > > > But I still think it's fairly terrible to get a (flawed) carbon copy of > > > the kretprobe code. > > > > Indeed. I would like to replace the trampoline code of kretprobe with > > rethook, eventually. There is no reason why we keep the clone. > > (But I need more arch maintainers help for that, there are too many > > archs implemented kretprobes) > > FWIW, I'm more than happy to help on the arm64 side if you could Cc me for > that; I'm aware of other things in this area I'd like to clean up for > backtracing, too. Thank you for your warm help. OK, let me update and submit the rethook for arm64 :-) Thanks. -- Masami Hiramatsu