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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4ECC2C433F5 for ; Tue, 19 Apr 2022 08:54:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C60FA6B00CC; Tue, 19 Apr 2022 04:54:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C110B6B00CF; Tue, 19 Apr 2022 04:54:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B006A6B00D3; Tue, 19 Apr 2022 04:54:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id A059F6B00CC for ; Tue, 19 Apr 2022 04:54:08 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 51B6B8249980 for ; Tue, 19 Apr 2022 08:54:08 +0000 (UTC) X-FDA: 79373016576.28.4B05DF8 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf23.hostedemail.com (Postfix) with ESMTP id 4A873140012 for ; Tue, 19 Apr 2022 08:54:06 +0000 (UTC) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KjHbT6Y5vzFqSY; Tue, 19 Apr 2022 16:51:33 +0800 (CST) Received: from dggpemm500001.china.huawei.com (7.185.36.107) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 19 Apr 2022 16:54:03 +0800 Received: from [10.174.177.243] (10.174.177.243) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 19 Apr 2022 16:54:03 +0800 Message-ID: <477dcc83-4298-b7e4-3a6a-c8fa23b27d01@huawei.com> Date: Tue, 19 Apr 2022 16:54:02 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: [PATCH v3 1/4] hugetlb: Fix wrong use of nr_online_nodes Content-Language: en-US To: Andrew Morton CC: Peng Liu , , , , , , , , References: <20220413032915.251254-1-liupeng256@huawei.com> <20220413032915.251254-2-liupeng256@huawei.com> <20220415020927.x7ylevbd5uaevfyt@offworld> <08896d0c-8821-000e-4cc2-9e64beda167f@huawei.com> <1407c3bb-89c4-ae11-7b09-d42115ab693e@huawei.com> <20220418214040.419a2e17254eb33f68f94b59@linux-foundation.org> From: Kefeng Wang In-Reply-To: <20220418214040.419a2e17254eb33f68f94b59@linux-foundation.org> Content-Type: text/plain; charset="UTF-8"; format=flowed X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 4A873140012 X-Stat-Signature: 39i7eytk79qwfnabroxpadjnaixd8rhs Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf23.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com X-Rspam-User: X-HE-Tag: 1650358446-362995 Content-Transfer-Encoding: quoted-printable 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 2022/4/19 12:40, Andrew Morton wrote: > On Sat, 16 Apr 2022 09:21:45 +0800 Kefeng Wang wrote: > >> On 2022/4/15 13:41, Kefeng Wang wrote: >>> On 2022/4/15 10:09, Davidlohr Bueso wrote: >>>> On Wed, 13 Apr 2022, Peng Liu wrote: >>>> >>>>> Certain systems are designed to have sparse/discontiguous nodes. In >>>>> this case, nr_online_nodes can not be used to walk through numa nod= e. >>>>> Also, a valid node may be greater than nr_online_nodes. >>>>> >>>>> However, in hugetlb, it is assumed that nodes are contiguous. Reche= ck >>>>> all the places that use nr_online_nodes, and repair them one by one= . >>>>> >>>>> Suggested-by: David Hildenbrand >>>>> Fixes: 4178158ef8ca ("hugetlbfs: fix issue of preallocation of >>>>> gigantic pages can't work") >>>>> Fixes: b5389086ad7b ("hugetlbfs: extend the definition of hugepages >>>>> parameter to support node allocation") >>>>> Fixes: e79ce9832316 ("hugetlbfs: fix a truncation issue in hugepage= s >>>>> parameter") >>>>> Fixes: f9317f77a6e0 ("hugetlb: clean up potential spectre issue >>>>> warnings") >>>>> Signed-off-by: Peng Liu >>>>> Reviewed-by: Baolin Wang >>>>> Reviewed-by: Mike Kravetz >>>> Reviewed-by: Davidlohr Bueso >>>> >>>> ... but >>>> >>>>> --- >>>>> mm/hugetlb.c | 12 ++++++------ >>>>> 1 file changed, 6 insertions(+), 6 deletions(-) >>>>> >>>>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c >>>>> index b34f50156f7e..5b5a2a5a742f 100644 >>>>> --- a/mm/hugetlb.c >>>>> +++ b/mm/hugetlb.c >>>>> @@ -2979,7 +2979,7 @@ int __alloc_bootmem_huge_page(struct hstate >>>>> *h, int nid) >>>>> =C2=A0=C2=A0=C2=A0=C2=A0struct huge_bootmem_page *m =3D NULL; /* i= nitialize for clang */ >>>>> =C2=A0=C2=A0=C2=A0=C2=A0int nr_nodes, node; >>>>> >>>>> -=C2=A0=C2=A0=C2=A0 if (nid !=3D NUMA_NO_NODE && nid >=3D nr_online= _nodes) >>>>> +=C2=A0=C2=A0=C2=A0 if (nid !=3D NUMA_NO_NODE && !node_online(nid)) >>>> afaict null_blk could also use this, actually the whole thing wants = a >>>> helper - node_valid()? >>>> >>> This one should be unnecessary, and this patch looks has a bug, >>> >>> if a very nid passed to node_online(), it may crash,=C2=A0 could you >>> re-check it, >>> >>> see my changes below, >>> >>> 1) add tmp check against MAX_NUMNODES before node_online() check, >>> >>> =C2=A0=C2=A0=C2=A0 and move it after=C2=A0get tmp in hugepages_setup= () , this could cover >>> both per-node alloc and normal alloc >> sorry=EF=BC=8Cfor normal alloc, tmp is the number of huge pages, we do= n't=C2=A0 need >> the movement, =C2=A0 only add tmp >=3D MAX_NUMNODES is ok >> > Does the v4 patch address the issues which were raised in this thread? Yes=EF=BC=8C v4 has fix this. > > > --- a/mm/hugetlb.c~hugetlb-fix-wrong-use-of-nr_online_nodes-v4 > +++ a/mm/hugetlb.c > @@ -2986,8 +2986,6 @@ int __alloc_bootmem_huge_page(struct hst > struct huge_bootmem_page *m =3D NULL; /* initialize for clang */ > int nr_nodes, node; > =20 > - if (nid !=3D NUMA_NO_NODE && !node_online(nid)) > - return 0; > /* do node specific alloc */ > if (nid !=3D NUMA_NO_NODE) { > m =3D memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(= h), > @@ -4174,7 +4172,7 @@ static int __init hugepages_setup(char * > pr_warn("HugeTLB: architecture can't support node specific alloc,= ignoring!\n"); > return 0; > } > - if (!node_online(tmp)) > + if (tmp >=3D MAX_NUMNODES || !node_online(tmp)) > goto invalid; > node =3D array_index_nospec(tmp, MAX_NUMNODES); > p +=3D count + 1; > _ > > .