From nobody Sat Jun 20 16:30:59 2026 Received: from canpmsgout04.his.huawei.com (canpmsgout04.his.huawei.com [113.46.200.219]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4804B2D3A69 for ; Mon, 13 Apr 2026 11:57:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.219 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776081466; cv=none; b=iHQBW87kUfOAOustIYmrCWEo/vGg3qBZl+RxCBH25n1WhLZ9Q+FwlIQ07OPBaCjeLZTG8ICE4vsopporL/B+graB9McP8+K4aGt0x+QPwErZCf+4PzRaI9eAW6oZe2jTZ7BfZjRLc9rSXXvOXXPnvUL5SrRkrxY4iQde1NxzmY0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776081466; c=relaxed/simple; bh=X1xzqzDe3zJbbAs79epyWJClbd7dJ/a05nKQfsRm06c=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=A02+fLPyDq/xAcmPbxUGgbgD/zcXhn2R1ZRXE0c2asO176SK8ye166LHQ8kx0RrkyOTk8rS7v4rYKZKl/1tKr5wW/fbvs5v8qCAh0tJN+8JtMBJMmVMD2Rq/0SbVo8hZ1gyqYaSHZ8BJjTpYN0w2MRZI+u/tw6PP4LxZ+v+LL3s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=rrxT3npE; arc=none smtp.client-ip=113.46.200.219 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="rrxT3npE" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=N2hsu1XgGKKp0f7imiVwOnA9Wx7XWP12pLWakH4tpxE=; b=rrxT3npEG1rPDv9YwYxhNHGSCkp5W+BolP72RSDTvHNtHP8f1Lw4Ui6IaeXBbVrk/e73AbkyG T0YLingRqKo0FmPyy+uJeBYMDjImUoB0pwVGSypcLzQ1YG3hCZhIQv4pe3AusyMVaaCH//qxDFb Bp3ASnlcd8s3y6dvcYd9naY= Received: from mail.maildlp.com (unknown [172.19.163.0]) by canpmsgout04.his.huawei.com (SkyGuard) with ESMTPS id 4fvQjN5rpmz1prLd; Mon, 13 Apr 2026 19:51:20 +0800 (CST) Received: from dggpemf200002.china.huawei.com (unknown [7.185.36.244]) by mail.maildlp.com (Postfix) with ESMTPS id CC81E40574; Mon, 13 Apr 2026 19:57:40 +0800 (CST) Received: from huawei.com (10.50.87.109) by dggpemf200002.china.huawei.com (7.185.36.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 13 Apr 2026 19:57:40 +0800 From: Yang Yingliang To: , , , , , , , CC: , , , Subject: [PATCH -next] mm: make sure freeram is smaller than totalram Date: Mon, 13 Apr 2026 19:57:36 +0800 Message-ID: <20260413115736.1237680-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To dggpemf200002.china.huawei.com (7.185.36.244) Content-Type: text/plain; charset="utf-8" The memory stat is not done in real time, it have some gap with real value. In CPU-less NUMA node, the values of MemTotal and MemFree can be nearly equal, the gap may cause MemFree bigger than MemTotal, it leads MemUsed is negative which print as a large positive number. cat /sys/devices/system/node/node17/meminfo Node 17 MemTotal: 4194304 kB Node 17 MemFree: 4195552 kB Node 17 MemUsed: 18446744073709550368 kB Node 17 Active: 52 kB Node 17 Inactive: 320 kB Node 17 Active(anon): 0 kB Node 17 Inactive(anon): 0 kB Node 17 Active(file): 52 kB Node 17 Inactive(file): 320 kB Node 17 Unevictable: 0 kB Node 17 Mlocked: 0 kB Node 17 Dirty: 0 kB Node 17 Writeback: 0 kB Node 17 FilePages: 372 kB Node 17 Mapped: 320 kB Node 17 AnonPages: 0 kB Node 17 Shmem: 0 kB Node 17 KernelStack: 0 kB Node 17 PageTables: 0 kB Node 17 NFS_Unstable: 0 kB Node 17 Bounce: 0 kB Node 17 WritebackTmp: 0 kB Node 17 KReclaimable: 0 kB Node 17 Slab: 0 kB Node 17 SReclaimable: 0 kB Node 17 SUnreclaim: 0 kB Node 17 AnonHugePages: 79872 kB Node 17 ShmemHugePages: 0 kB Node 17 ShmemPmdMapped: 0 kB Node 17 FileHugePages: 0 kB Node 17 FilePmdMapped: 0 kB Node 17 HugePages_Total: 0 Node 17 HugePages_Free: 0 Node 17 HugePages_Surp: 0 To avoid this exception by refreshing vm_stat, when MemFree is bigger than MemTotal. Signed-off-by: Yang Yingliang --- include/linux/vmstat.h | 1 + mm/show_mem.c | 10 ++++++++++ mm/vmstat.c | 15 ++++++++++----- 3 files changed, 21 insertions(+), 5 deletions(-) diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index 3c9c266cf782..6a7d2f3757b0 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -259,6 +259,7 @@ extern unsigned long node_page_state(struct pglist_data= *pgdat, enum node_stat_item item); extern unsigned long node_page_state_pages(struct pglist_data *pgdat, enum node_stat_item item); +extern int refresh_node_page_state(void); extern void fold_vm_numa_events(void); #else #define sum_zone_node_page_state(node, item) global_zone_page_state(item) diff --git a/mm/show_mem.c b/mm/show_mem.c index 43aca5a2ac99..dc8d2b6056d3 100644 --- a/mm/show_mem.c +++ b/mm/show_mem.c @@ -106,6 +106,16 @@ void si_meminfo_node(struct sysinfo *val, int nid) val->totalram =3D managed_pages; val->sharedram =3D node_page_state(pgdat, NR_SHMEM); val->freeram =3D sum_zone_node_page_state(nid, NR_FREE_PAGES); + if (val->freeram > val->totalram) { + int err =3D refresh_node_page_state(); + if (err) + val->freeram =3D val->totalram; + else + val->freeram =3D sum_zone_node_page_state(nid, NR_FREE_PAGES); + + if (val->freeram > val->totalram) + val->freeram =3D val->totalram; + } val->totalhigh =3D managed_highpages; val->freehigh =3D free_highpages; val->mem_unit =3D PAGE_SIZE; diff --git a/mm/vmstat.c b/mm/vmstat.c index f534972f517d..96a2e03ec83e 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -881,6 +881,11 @@ static bool refresh_cpu_vm_stats(bool do_pagesets) return changed; } =20 +static void refresh_vm_stats(struct work_struct *work) +{ + refresh_cpu_vm_stats(true); +} + /* * Fold the data for an offline cpu into the global array. * There cannot be any access by the offline cpu and therefore @@ -1024,6 +1029,11 @@ unsigned long node_page_state(struct pglist_data *pg= dat, =20 return node_page_state_pages(pgdat, item); } + +int refresh_node_page_state(void) +{ + return schedule_on_each_cpu(refresh_vm_stats); +} #endif =20 /* @@ -1970,11 +1980,6 @@ static int sysctl_stat_interval __read_mostly =3D HZ; static int vmstat_late_init_done; =20 #ifdef CONFIG_PROC_FS -static void refresh_vm_stats(struct work_struct *work) -{ - refresh_cpu_vm_stats(true); -} - static int vmstat_refresh(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { --=20 2.25.1