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 7B159C2BD09 for ; Mon, 1 Jul 2024 07:14:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EC8076B008C; Mon, 1 Jul 2024 03:14:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E778B6B0095; Mon, 1 Jul 2024 03:14:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CCA3D6B0096; Mon, 1 Jul 2024 03:14:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id AAD1D6B008C for ; Mon, 1 Jul 2024 03:14:36 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 5EF7C80AD8 for ; Mon, 1 Jul 2024 07:14:36 +0000 (UTC) X-FDA: 82290320952.09.219C962 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf13.hostedemail.com (Postfix) with ESMTP id 2D1C52000B for ; Mon, 1 Jul 2024 07:14:33 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=ZMCi4p9r; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf13.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719818050; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=VZtx1TI9CHzvib+rgK9jrkHHn0d7MZ2Du3tOelQ2tzg=; b=61wu9DhFKROBiy2qovJ8Vt0Fc7/Fe8I01Z5ot25sgJbrlcvsMdKiG6EMJ2Gn7ULjNEw+FS Das8rTnC4Xoj+VcqzjebFbIUQTOS2qsRjCF5W8a2W1IVt6F69EgYN+21RtwMoz4qadGZ2o QufhPEE4tFtoD+fOY9FmV5LheNhcUsE= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719818050; a=rsa-sha256; cv=none; b=BamtBp0uI1wOqvBs6EumhTtO1n3q2qKaUyS5YJhwH98mHbRNHsHBtQY4gRezjipVt7Bhe1 b5n64WZugr1VpOt/ijWXne6yYuwSfAY4OJA/DxhrnoOs6r7+rUegsqS/w4Es0vI3EioBj9 DbZD215olNiXy2qPxyGfksXn04qaYHY= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=ZMCi4p9r; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf13.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719818073; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=VZtx1TI9CHzvib+rgK9jrkHHn0d7MZ2Du3tOelQ2tzg=; b=ZMCi4p9rrezQigxRVcDirrOREzu36ZgPNuDrzVpne0f4FkpvRbi4am4u8aYuz0ROc/Tl6n Z+j5J29ki20GQa1OOxL6pUY+zOvxXGTOl8gBfTURAcBFKhySfgzKLy09QTiHDadbMnbsAu aKzoJurR+86qUvRhLAupnq73ZlJaIqg= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-643-PtrT5skrPoKxUXPNW9hTpw-1; Mon, 01 Jul 2024 03:14:32 -0400 X-MC-Unique: PtrT5skrPoKxUXPNW9hTpw-1 Received: by mail-wr1-f69.google.com with SMTP id ffacd0b85a97d-36710f4d5c9so1876158f8f.3 for ; Mon, 01 Jul 2024 00:14:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719818071; x=1720422871; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=VZtx1TI9CHzvib+rgK9jrkHHn0d7MZ2Du3tOelQ2tzg=; b=lIDNrVwzVzssJhhm+b3e0/zI+mId8PcKBTnnNs2sM0oH7hX/3abrGmsLog2Sv2rlVm BUUBrapwA2OJJCNBrUr0zeee/8yOd976swdkzPJYllUGDACoyGTgCRVuNkZ2WoyYGPL1 1S5LNDO4bv7n2d4NWfLmg9TvkD1UQvHC2HNQM6yBKG/TL34v6xlgjCaO1N1z0N6l+Bfm C+06leq7Kmnfl8s5UThQGeW1TzeDwrOGW8hxZNUfRNZxvFCRpx2H7FEM8KvCCu579XVb Ae9QueLND95GlHI1IFmDakUeHNNNr45mVfL56CgBMJjXuHJOl+olqdEsCSfz6EfouXTv YwQg== X-Forwarded-Encrypted: i=1; AJvYcCX5LXsrrlc5PbcfTL/hYzE4L0Y0Fc05HiSV7Rge9iaxkxjZbHRxKmqqrMnAxk+ZMcPh6u1FJC2iY+sz5Dst74jEHcU= X-Gm-Message-State: AOJu0YzhMj1ibkKOlM6lrJLl7mntigDogmODFy6jJOH+p6rCVKMjUNum WjWV/6ZpA9A0f75IeNlXoHRXM/h3OkC/ybUIujwc733KfLMIRrOw8gNtmxHneKDS9S9I8jy6duU 62k/pCNB78biSORkg9vm/6tQWNYjvqWSY8CQvhDUxh6zzMi6S X-Received: by 2002:a5d:6483:0:b0:367:4d9d:56a5 with SMTP id ffacd0b85a97d-367757247fdmr3004292f8f.44.1719818071155; Mon, 01 Jul 2024 00:14:31 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFHBkH8EmNBYc0VbYj0wklpvddeAsgKKczTBqdE81snbQRQuE6ATiW0y8fyo2ESK0CI0aeIZw== X-Received: by 2002:a5d:6483:0:b0:367:4d9d:56a5 with SMTP id ffacd0b85a97d-367757247fdmr3004280f8f.44.1719818070682; Mon, 01 Jul 2024 00:14:30 -0700 (PDT) Received: from ?IPV6:2003:cb:c72e:2200:7ed7:c239:d423:3b31? (p200300cbc72e22007ed7c239d4233b31.dip0.t-ipconnect.de. [2003:cb:c72e:2200:7ed7:c239:d423:3b31]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3675a0fb92fsm9278687f8f.88.2024.07.01.00.14.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 01 Jul 2024 00:14:30 -0700 (PDT) Message-ID: <68b4b249-ceac-4d5b-9d15-a2e33a1187e5@redhat.com> Date: Mon, 1 Jul 2024 09:14:29 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [BUG ?] Offline Memory gets stuck in offline_pages() To: "Zhijian Li (Fujitsu)" , "linux-mm@kvack.org" , "linux-cxl@vger.kernel.org" Cc: "dan.j.williams@intel.com" , "Yasunori Gotou (Fujitsu)" , Oscar Salvador , "akpm@linux-foundation.org" References: <6a07125f-e720-404c-b2f9-e55f3f166e85@fujitsu.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <6a07125f-e720-404c-b2f9-e55f3f166e85@fujitsu.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 2D1C52000B X-Stat-Signature: 5pxkekh6m6tdouqb539hwqizijxbkikg X-Rspam-User: X-HE-Tag: 1719818073-104131 X-HE-Meta: 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 B/XR+6pQ 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 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: List-Subscribe: List-Unsubscribe: On 01.07.24 03:25, Zhijian Li (Fujitsu) wrote: > Hi all > > > Overview: > During testing the CXL memory hotremove, we noticed that `daxctl offline-memory dax0.0` > would get stuck forever sometimes. daxctl offline-memory dax0.0 will write "offline" to > /sys/devices/system/memory/memoryNNN/state. Hi, See Documentation/admin-guide/mm/memory-hotplug.rst " Further, when running into out of memory situations while migrating pages, or when still encountering permanently unmovable pages within ZONE_MOVABLE (-> BUG), memory offlining will keep retrying until it eventually succeeds. When offlining is triggered from user space, the offlining context can be terminated by sending a signal. A timeout based offlining can easily be implemented via:: % timeout $TIMEOUT offline_block | failure_handling " > > Workaround: > When it happens, we can type Ctrl-C to abort it and then retry again. > Then the CXL memory is able to offline successfully. > > Where the kernel gets stuck: > After digging into the kernel, we found that when the issue occurs, the kernel > is stuck in the outer loop of offline_pages(). Below is a piece of the > highlighted offline_pages(): > > ``` > int __ref offline_pages() > { > do { // outer loop > pfn = start_pfn; > do { > ret = scan_movable_pages(pfn, end_pfn, &pfn); // It returns -ENOENT > if (!ret) > do_migrate_range(pfn, end_pfn); // Not reach here > } while (!ret); > ret = test_pages_isolated(start_pfn, end_pfn, MEMORY_OFFLINE); > } while (ret); // ret is -EBUSY > } > ``` > > In this case, we dumped the first page that cannot be isolated (see dump_page below), it's > content does not change in each iteration.: > ``` > Jun 28 15:29:26 linux kernel: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7980dd > Jun 28 15:29:26 linux kernel: flags: 0x9fffffc0000000(node=2|zone=3|lastcpupid=0x1fffff) > Jun 28 15:29:26 linux kernel: raw: 009fffffc0000000 ffffdfbd9e603788 ffffd4f0ffd97ef0 0000000000000000 > Jun 28 15:29:26 linux kernel: raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 > Jun 28 15:29:26 linux kernel: page dumped because: trouble page... Are you sure that's the problematic page? refcount:0 Indicates that the page is free. But maybe it does not have PageBuddy() set. It could also be that this is a "tail" page of a PageBuddy() page, and somehow we always end up on the tail in test_pages_isolated(). Which kernel + architecture are you testing with? > ``` > > Every time the issue occurs, the content of the page structure is similar. > > Questions: > Q1. Is this behavior expected? At least for an OS administrator, it should return > promptly (success or failure) instead of hanging indefinitely. It's expected that it might take a long time (possibly forever) in corner cases. See documentation. But it's likely unexpected that we have some problematic page here. > Q2. Regarding the offline_pages() function, encountering such a page indeed causes > an endless loop. Shouldn't another part of the kernel timely changed the state > of this page? There are various things that can go wrong. One issue might be that we try migrating a page but continuously fail to allocate memory to be used as a migration target. It seems unlikely with the page you dumped above, though. Do you maybe have that CXL memory be on a separate "fake" NUMA node, and your workload mbind() itself to that NUMA node, possibly refusing to migrate somewhere else? > > When I use the workaround mentioned above (Ctrl-C and try offline again), I find > that the page state changes (see dump_page below): > ``` > Jun 28 15:33:12 linux kernel: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7980dd > Jun 28 15:33:12 linux kernel: flags: 0x9fffffc0000000(node=2|zone=3|lastcpupid=0x1fffff) > Jun 28 15:33:12 linux kernel: raw: 009fffffc0000000 dead000000000100 dead000000000122 0000000000000000 > Jun 28 15:33:12 linux kernel: raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 > Jun 28 15:33:12 linux kernel: page dumped because: previous trouble page > ``` > > What our test does: > We have a CXL memory device, which is configured as kmem and online into the MOVABLE > zone as NUMA node2. We run two processes, consume-memory and offline-memory, in parallel, > see the pseudo code below: > > ``` > main() > { > if (fork() == 0) > numactl -m 2 ./consume-memory What exactly does "consume-memory" do? Does it involve hugetlb maybe? -- Cheers, David / dhildenb