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_CR_TRAILER,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 92D92C4708A for ; Wed, 26 May 2021 18:13:13 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2F2D2613F1 for ; Wed, 26 May 2021 18:13:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2F2D2613F1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=techsingularity.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 68CBC6B006C; Wed, 26 May 2021 14:13:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6625B6B006E; Wed, 26 May 2021 14:13:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5504E6B0070; Wed, 26 May 2021 14:13:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0027.hostedemail.com [216.40.44.27]) by kanga.kvack.org (Postfix) with ESMTP id 2374A6B006C for ; Wed, 26 May 2021 14:13:12 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B33414DB8 for ; Wed, 26 May 2021 18:13:11 +0000 (UTC) X-FDA: 78184178982.36.30002E4 Received: from outbound-smtp24.blacknight.com (outbound-smtp24.blacknight.com [81.17.249.192]) by imf18.hostedemail.com (Postfix) with ESMTP id 4753320007FD for ; Wed, 26 May 2021 18:13:04 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail06.blacknight.ie [81.17.255.152]) by outbound-smtp24.blacknight.com (Postfix) with ESMTPS id E659882017 for ; Wed, 26 May 2021 19:13:08 +0100 (IST) Received: (qmail 4224 invoked from network); 26 May 2021 18:13:08 -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 18:13:08 -0000 Date: Wed, 26 May 2021 19:13:07 +0100 From: Mel Gorman To: Andrii Nakryiko Cc: Andrew Morton , Michal Suchanek , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , open list , Arnaldo Carvalho de Melo , 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: <20210526181306.GZ30378@techsingularity.net> References: <20210526080741.GW30378@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) X-Rspamd-Queue-Id: 4753320007FD Authentication-Results: imf18.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf18.hostedemail.com: domain of mgorman@techsingularity.net designates 81.17.249.192 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net X-Rspamd-Server: rspam04 X-Stat-Signature: q5p1wo5zs3orxednii1bdn1p8gm6z1h4 X-HE-Tag: 1622052784-926356 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, May 26, 2021 at 09:57:31AM -0700, Andrii Nakryiko wrote: > > This patch checks for older versions of pahole and forces struct pagesets > > to be non-zero sized as a workaround when CONFIG_DEBUG_INFO_BTF is set. A > > warning is omitted so that distributions can update pahole when 1.22 > > s/omitted/emitted/ ? > Yes. > > is released. > > > > Reported-by: Michal Suchanek > > Reported-by: Hritik Vijay > > Debugged-by: Andrii Nakryiko > > Signed-off-by: Mel Gorman > > --- > > Looks good! I verified that this does fix the issue on the latest > linux-next tree, thanks! > Excellent > One question, should > > Fixes: 5716a627517d ("mm/page_alloc: convert per-cpu list protection > to local_lock") > > be added to facilitate backporting? > The git commit is not stable because the patch "mm/page_alloc: convert per-cpu list protection to local_lock" is in Andrew's mmotm tree which is quilt based. I decided not to treat the patch as a fix because the patch is not wrong as such, it's a limitation of an external tool. However, I would expect both the problematic patch and the BTF workaround to go in during the same merge window so backports to -stable should not be required. > Either way: > > Acked-by: Andrii Nakryiko > Tested-by: Andrii Nakryiko > Thanks! -- Mel Gorman SUSE Labs