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 X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 582FCC31E44 for ; Fri, 14 Jun 2019 08:11:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CDAF2080A for ; Fri, 14 Jun 2019 08:11:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="F751dU49" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726494AbfFNILa (ORCPT ); Fri, 14 Jun 2019 04:11:30 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:60474 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726083AbfFNILa (ORCPT ); Fri, 14 Jun 2019 04:11:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=USG8NWPdVBgY5Ej2X/EDSC1YVY6FY+uYmg/tOOLTTFo=; b=F751dU49JkcOCni8fL2Qt0e2R 526jP56gRAGvqGQopmBVt6ByAtqWtTPuVRjmAQFCMc85IhMtr9ojAqwZyKTL7iA6waWtkxWITHOoM f8/MVsucKiaQz/8neYKfB6i7z78g64oPDzJNOqZdb+gRvysCzZrs1dOBUgy7lsVSaw/8ncAORS4d+ QEZXCl6TlW53imd7FYTVEMyF7lHl9bQpZ+JYkIV3vFtbfPRLeStaAM7JLFjp/WHsQi6EAi0QhsBDO ZUbBHyY2kvgnsxG+2DA5/RgYbH6JyY1UakyxxTxhjgFqtFxyjSQulKXZdt1OWF3B39o7xiu96x6kK LosCUCu+Q==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hbhIs-0003ta-Ag; Fri, 14 Jun 2019 08:11:18 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id C40FB20A15636; Fri, 14 Jun 2019 10:11:16 +0200 (CEST) Date: Fri, 14 Jun 2019 10:11:16 +0200 From: Peter Zijlstra To: Alexei Starovoitov Cc: Josh Poimboeuf , x86@kernel.org, linux-kernel@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Kairui Song Subject: Re: [PATCH 2/9] objtool: Fix ORC unwinding in non-JIT BPF generated code Message-ID: <20190614081116.GU3436@hirez.programming.kicks-ass.net> References: <99c22bbd79e72855f4bc9049981602d537a54e70.1560431531.git.jpoimboe@redhat.com> <20190613205710.et5fywop4gfalsa6@ast-mbp.dhcp.thefacebook.com> <20190614012030.b6eujm7b4psu62kj@treble> <20190614070852.GQ3436@hirez.programming.kicks-ass.net> <20190614073536.d3xkhwhq3fuivwt5@ast-mbp.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190614073536.d3xkhwhq3fuivwt5@ast-mbp.dhcp.thefacebook.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 14, 2019 at 12:35:38AM -0700, Alexei Starovoitov wrote: > On Fri, Jun 14, 2019 at 09:08:52AM +0200, Peter Zijlstra wrote: > > On Thu, Jun 13, 2019 at 08:20:30PM -0500, Josh Poimboeuf wrote: > > > On Thu, Jun 13, 2019 at 01:57:11PM -0700, Alexei Starovoitov wrote: > > > > > > and to patches 8 and 9. > > > > > > Well, it's your code, but ... can I ask why? AT&T syntax is the > > > standard for Linux, which is in fact the OS we are developing for. > > > > I agree, all assembly in Linux is AT&T, adding Intel notation only > > serves to cause confusion. > > It's not assembly. It's C code that generates binary and here > we're talking about comments. And comments are useless if they don't clarify. Intel syntax confuses. > I'm sure you're not proposing to do: > /* mov src, dst */ > #define EMIT_mov(DST, SRC) \ > right? Which is why Josh reversed both of them. The current Intel order is just terribly confusing. And I don't see any of the other JITs having confusing comments like this. > bpf_jit_comp.c stays as-is. Enough of it. I think you're forgetting this is also arch/x86 code, and no, it needs changes because its broken wrt unwinding.