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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 7A20AC0650E for ; Wed, 3 Jul 2019 19:46:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AF792085A for ; Wed, 3 Jul 2019 19:46:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726581AbfGCTqS (ORCPT ); Wed, 3 Jul 2019 15:46:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59982 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726490AbfGCTqS (ORCPT ); Wed, 3 Jul 2019 15:46:18 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 54FDF3086200; Wed, 3 Jul 2019 19:46:18 +0000 (UTC) Received: from treble (ovpn-112-31.rdu2.redhat.com [10.10.112.31]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5246E91F54; Wed, 3 Jul 2019 19:46:17 +0000 (UTC) Date: Wed, 3 Jul 2019 14:46:14 -0500 From: Josh Poimboeuf To: Randy Dunlap Cc: Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Peter Zijlstra Subject: Re: linux-next: Tree for Jul 2 (objtool) Message-ID: <20190703194614.6bsyfspnpcf4dhfj@treble> References: <20190702195158.79aa5517@canb.auug.org.au> <20190703164458.imjawnoczygb2vvd@treble> <20190703194528.7kk7v44whdp7ol5a@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190703194528.7kk7v44whdp7ol5a@treble> User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Wed, 03 Jul 2019 19:46:18 +0000 (UTC) Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Wed, Jul 03, 2019 at 02:45:28PM -0500, Josh Poimboeuf wrote: > On Wed, Jul 03, 2019 at 10:23:21AM -0700, Randy Dunlap wrote: > > On 7/3/19 9:44 AM, Josh Poimboeuf wrote: > > > On Tue, Jul 02, 2019 at 11:47:02AM -0700, Randy Dunlap wrote: > > >> On 7/2/19 2:51 AM, Stephen Rothwell wrote: > > >>> Hi all, > > >>> > > >>> Changes since 20190701: > > >>> > > >> > > >> on x86_64: > > >> > > >> kernel/bpf/core.o: warning: objtool: ___bpf_prog_run()+0x22: can't find switch jump table > > > > > > I don't see it on current linux-next/master. Can you share the config > > > and .o? > > > > > > > This warning happened in 6 of 10 builds for 20190702. > > > > Today (20190703) I don't see it at all, but I see this instead: > > kernel/bpf/core.o: warning: objtool: ___bpf_prog_run()+0xa3: sibling call from callable instruction with modified stack frame > > > > Kernel (rand)config file and .o file for 20190702 are attached. > > Thanks, I'm able to recreate the sibling call warning with a randconfig > on today's linux-next. > > GCC is doing some funky stuff. With my randconfig, ___bpf_prog_run() > has 166 indirect calls to its jump table. Seems (a bit!) excessive. s/calls/jumps/ obviously > > I'll need to look into it. > > -- > Josh -- Josh