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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 4066BC2B9F7 for ; Wed, 26 May 2021 08:15:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C0A861001 for ; Wed, 26 May 2021 08:15:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232026AbhEZIQv (ORCPT ); Wed, 26 May 2021 04:16:51 -0400 Received: from outbound-smtp08.blacknight.com ([46.22.139.13]:38375 "EHLO outbound-smtp08.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231410AbhEZIQt (ORCPT ); Wed, 26 May 2021 04:16:49 -0400 Received: from mail.blacknight.com (pemlinmail01.blacknight.ie [81.17.254.10]) by outbound-smtp08.blacknight.com (Postfix) with ESMTPS id 1C1961C3FEC for ; Wed, 26 May 2021 09:15:14 +0100 (IST) Received: (qmail 25045 invoked from network); 26 May 2021 08:15:13 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[84.203.23.168]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 26 May 2021 08:15:13 -0000 Date: Wed, 26 May 2021 09:15:11 +0100 From: Mel Gorman To: Andrii Nakryiko Cc: Michal Such?nek , bpf , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Networking , open list , Arnaldo Carvalho de Melo , Jiri Olsa , Hritik Vijay Subject: Re: BPF: failed module verification on linux-next Message-ID: <20210526081511.GX30378@techsingularity.net> References: <20210519141936.GV8544@kitsune.suse.cz> <20210525135101.GT30378@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org > On Tue, May 25, 2021 at 6:51 AM Mel Gorman wrote: > > > > On Mon, May 24, 2021 at 03:58:29PM -0700, Andrii Nakryiko wrote: > > > > It took me a while to reliably bisect this, but it clearly points to > > > > this commit: > > > > > > > > e481fac7d80b ("mm/page_alloc: convert per-cpu list protection to local_lock") > > > > > > > > > > Ok, so nothing weird about them. local_lock_t is designed to be > > > zero-sized unless CONFIG_DEBUG_LOCK_ALLOC is defined. > > > > > > But such zero-sized per-CPU variables are confusing pahole during BTF > > > generation, as now two different variables "occupy" the same address. > > > > > > Given this seems to be the first zero-sized per-CPU variable, I wonder > > > if it would be ok to make sure it's never zero-sized, while pahole > > > gets fixed and it's latest version gets widely packaged and > > > distributed. > > > > > > Mel, what do you think about something like below? Or maybe you can > > > advise some better solution? > > > > > > > Ouch, something like that may never go away. How about just this? > > Yeah, that would work just fine, thanks! Would you like me to send a > formal patch or you'd like to do it? > Thanks Andrii for bisecting and debugging this, I used your analysis in the changelog which I hope is ok. For future mailing list searches based on the same bug, I sent a formal patch https://lore.kernel.org/r/20210526080741.GW30378@techsingularity.net > > diff --git a/scripts/rust-version.sh b/scripts/rust-version.sh > > old mode 100644 > > new mode 100755 > > Probably didn't intend to include this? > That was an oversight when applying Andrew's mmotm tree which missed setting the permissions on rust-version.sh and broke build. -- Mel Gorman SUSE Labs