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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 4E12CC433B4 for ; Wed, 5 May 2021 01:37:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3594C611AB for ; Wed, 5 May 2021 01:37:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231680AbhEEBit (ORCPT ); Tue, 4 May 2021 21:38:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:41750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231124AbhEEBis (ORCPT ); Tue, 4 May 2021 21:38:48 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DDF2D61182; Wed, 5 May 2021 01:37:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620178672; bh=8YIVxARpDwdJ824qQd5KRYSfeQowbwustDIsLRszFBA=; h=Date:From:To:Subject:In-Reply-To:From; b=Qb9m3EJBRgKhNTLO1ULF5qj+tRQbG1l8UYcGy5DiQ4RjwpqmV3HrhB6wovPr1kB6m qRvvdf199K+x0tcOpIcQBiZzC1lmO6hCnrNnZxyAwC0LEB8mE8SHuSLZoODcI8z/CN WSA1APaqe78m6ap/HVdadx8r7JHDm9F7GnDKIfv0= Date: Tue, 04 May 2021 18:37:51 -0700 From: Andrew Morton To: akpm@linux-foundation.org, guro@fb.com, hannes@cmpxchg.org, hughd@google.com, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 096/143] mm: restore node stat checking in /proc/sys/vm/stat_refresh Message-ID: <20210505013751.BS8Z6yw4k%akpm@linux-foundation.org> In-Reply-To: <20210504183219.a3cc46aee4013d77402276c5@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Hugh Dickins Subject: mm: restore node stat checking in /proc/sys/vm/stat_refresh v4.7 52b6f46bc163 ("mm: /proc/sys/vm/stat_refresh to force vmstat update") introduced vmstat_refresh(), with its vmstat underflow checking; then v4.8 75ef71840539 ("mm, vmstat: add infrastructure for per-node vmstats") split NR_VM_NODE_STAT_ITEMS out of NR_VM_ZONE_STAT_ITEMS without updating vmstat_refresh(): so it has been missing out much of the vmstat underflow checking ever since. Reinstate it. Thanks to Roman Gushchin for tangentially pointing this out. Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2102251502240.13363@eggly.anvils Signed-off-by: Hugh Dickins Cc: Roman Gushchin Cc: Johannes Weiner Cc: Michal Hocko Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- mm/vmstat.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/mm/vmstat.c~mm-restore-node-stat-checking-in-proc-sys-vm-stat_refresh +++ a/mm/vmstat.c @@ -1875,6 +1875,14 @@ int vmstat_refresh(struct ctl_table *tab } } #endif + for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { + val = atomic_long_read(&vm_node_stat[i]); + if (val < 0) { + pr_warn("%s: %s %ld\n", + __func__, node_stat_name(i), val); + err = -EINVAL; + } + } if (err) return err; if (write) _