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 B3F43C2B9F4 for ; Mon, 28 Jun 2021 15:29:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9453261492 for ; Mon, 28 Jun 2021 15:29:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237165AbhF1Pbb (ORCPT ); Mon, 28 Jun 2021 11:31:31 -0400 Received: from outbound-smtp29.blacknight.com ([81.17.249.32]:39215 "EHLO outbound-smtp29.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235256AbhF1PGR (ORCPT ); Mon, 28 Jun 2021 11:06:17 -0400 Received: from mail.blacknight.com (pemlinmail06.blacknight.ie [81.17.255.152]) by outbound-smtp29.blacknight.com (Postfix) with ESMTPS id 0CC88BEC93 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) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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