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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 07DEBC47089 for ; Thu, 27 May 2021 09:19:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D367E6105A for ; Thu, 27 May 2021 09:19:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235710AbhE0JVP (ORCPT ); Thu, 27 May 2021 05:21:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235608AbhE0JVN (ORCPT ); Thu, 27 May 2021 05:21:13 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A1BEC061574; Thu, 27 May 2021 02:19:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=iRsknJTfFiEDd9n74h43kOIWLR9thmAzm1ZrB74a5Xk=; b=Mt+PC76TyiEwy+b6L48ycifDAR XKE8hldzILOrEh24nLs1DSsELIQas2IMv96tixj0ygC3f1Lv3VEvRBeKiKDdtAWb19AjM5LU/k5h/ x3XDVHdV417fF1H3Ioq5EQ/NwRnCfBr+Fc1RIrEBzMubdx7Ex60adikqLp3aVUdx7YpCkeCFVn2k6 gyVeE5GIlQjhhQX6EMJnfTUpNzx1SHu06QnzDFpnSeKq7kiP0aebbIVgqScJDxi7FexSCpNSXgBHN 1vL261F7MmvNoS69Ac4LUN+xB6UnMqaSfWnV3cPlTxon563qfBxvhw3p6iNh2RBqXL5IZxp9HvQB8 7v4DbJ5Q==; Received: from hch by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lmC9l-005NI5-1e; Thu, 27 May 2021 09:18:41 +0000 Date: Thu, 27 May 2021 10:18:21 +0100 From: Christoph Hellwig To: Mel Gorman Cc: Christoph Hellwig , Andrew Morton , Arnaldo Carvalho de Melo , Andrii Nakryiko , Michal Suchanek , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , open list , Jiri Olsa , Hritik Vijay , bpf , Linux-Net , Linux-MM Subject: Re: [PATCH] mm/page_alloc: Work around a pahole limitation with zero-sized struct pagesets Message-ID: References: <20210526080741.GW30378@techsingularity.net> <20210527090422.GA30378@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210527090422.GA30378@techsingularity.net> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 27, 2021 at 10:04:22AM +0100, Mel Gorman wrote: > What do you suggest as an alternative? > > I added Arnaldo to the cc as he tagged the last released version of > pahole (1.21) and may be able to tag a 1.22 with Andrii's fix for pahole > included. > > The most obvious alternative fix for this issue is to require pahole > 1.22 to set CONFIG_DEBUG_INFO_BTF but obviously a version 1.22 that works > needs to exist first and right now it does not. I'd be ok with this but > users of DEBUG_INFO_BTF may object given that it'll be impossible to set > the option until there is a release. Yes, disable BTF. Empty structs are a very useful feature that we use in various places in the kernel. We can't just keep piling hacks over hacks to make that work with a recent fringe feature.