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 C393DC49361 for ; Mon, 28 Jun 2021 15:03:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6BC7261425 for ; Mon, 28 Jun 2021 15:03:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BC7261425 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 9FEC28D005E; Mon, 28 Jun 2021 11:03:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9D5F38D0016; Mon, 28 Jun 2021 11:03:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C6318D005E; Mon, 28 Jun 2021 11:03:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0198.hostedemail.com [216.40.44.198]) by kanga.kvack.org (Postfix) with ESMTP id 5CFF58D0016 for ; Mon, 28 Jun 2021 11:03:52 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 4002E82499A8 for ; Mon, 28 Jun 2021 15:03:52 +0000 (UTC) X-FDA: 78303452304.03.7647EA5 Received: from outbound-smtp61.blacknight.com (outbound-smtp61.blacknight.com [46.22.136.249]) by imf23.hostedemail.com (Postfix) with ESMTP id 815BCA0010C9 for ; Mon, 28 Jun 2021 15:03:51 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail06.blacknight.ie [81.17.255.152]) by outbound-smtp61.blacknight.com (Postfix) with ESMTPS id 0C7A7FA926 for ; Mon, 28 Jun 2021 16:03:50 +0100 (IST) Received: (qmail 3938 invoked from network); 28 Jun 2021 15:03:49 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[84.203.17.255]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 28 Jun 2021 15:03:49 -0000 Date: Mon, 28 Jun 2021 16:03:48 +0100 From: Mel Gorman To: Dave Jones Cc: Andrew Morton , Dan Carpenter , Jesper Dangaard Brouer , Vlastimil Babka , Linux-MM , LKML , Linus Torvalds Subject: Re: [PATCH] mm/page_alloc: do bulk array bounds check after checking populated elements Message-ID: <20210628150348.GD3840@techsingularity.net> References: <20210618125102.GU30378@techsingularity.net> <20210628042759.GA19686@codemonkey.org.uk> <20210628115322.GA3840@techsingularity.net> <20210628144805.GA3687@codemonkey.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20210628144805.GA3687@codemonkey.org.uk> User-Agent: Mutt/1.10.1 (2018-07-13) Authentication-Results: imf23.hostedemail.com; dkim=none; spf=pass (imf23.hostedemail.com: domain of mgorman@techsingularity.net designates 46.22.136.249 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net; dmarc=none X-Stat-Signature: bikii9rike7yz177gf3m6u5nzac4cogi X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 815BCA0010C9 X-HE-Tag: 1624892631-432032 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 Mon, Jun 28, 2021 at 10:48:05AM -0400, Dave Jones wrote: > On Mon, Jun 28, 2021 at 12:53:23PM +0100, Mel Gorman wrote: > > > > This made it into 5.13 final, and completely breaks NFSD for me (Serving tcp v3 mounts). > > > Existing mounts on clients hang, as do new mounts from new clients. > > > Rebooting the server back to rc7 everything recovers. Bisect lands on > > > this commit. > > > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index ef2265f86b91..04220581579c 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > > @@ -5058,7 +5058,7 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, > > > > /* Already populated array? */ > > if (unlikely(page_array && nr_pages - nr_populated == 0)) > > - return 0; > > + return nr_populated; > > Yep, this works. > Thanks Dave, it passed a dbench test over NFS locally as well so I sent a proper version of the patch. Hopefully it'll be picked up relatively quickly and appear in a 5.13.1 release. -- Mel Gorman SUSE Labs