From patchwork Mon Feb 10 16:13:17 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13968152 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 C2C2EC02198 for ; Mon, 10 Feb 2025 16:13:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 16A90280001; Mon, 10 Feb 2025 11:13:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 11A9E6B0088; Mon, 10 Feb 2025 11:13:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F247B280001; Mon, 10 Feb 2025 11:13:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id D51576B0083 for ; Mon, 10 Feb 2025 11:13:29 -0500 (EST) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 61AC81A01E0 for ; Mon, 10 Feb 2025 16:13:29 +0000 (UTC) X-FDA: 83104530138.25.81F3209 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf09.hostedemail.com (Postfix) with ESMTP id 35A79140011 for ; Mon, 10 Feb 2025 16:13:27 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=KNhtOAIq; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf09.hostedemail.com: domain of dhildenb@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhildenb@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1739204007; a=rsa-sha256; cv=none; b=2RsRqVqHQX1Lg2mMS0TdQZ0enBUJRmez1yyhc9L0wO8RUu4AkZ9qBHRxb0fHup4RLBa3Iz AfNVYW2vzSPauvrbw5sHxnVbvIoFBRUbyacOEcZmvopMbaHCKt7vUPtXqyZShcKaz+GlEN uVxSW8lkj5HW9xxYtUTsuyKYYB24GkI= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=KNhtOAIq; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf09.hostedemail.com: domain of dhildenb@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhildenb@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1739204007; 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: references:dkim-signature; bh=MEQtKpqipC+PTN4Th/631XgtJVl5K1IqFh4MSRtsc+U=; b=wVXZmRQKUd1KkvwBlmC8zDMGbhsmcetpQR45CXZreB1KyT+dWdbvWDAV8aJIHDYkn4LCJ5 u26/WiuOzceuGi9vNl+AB0oGvpcCnsvZRQh2DpLixqqc/z6UnbLFySbz3+T+EuuGc0WIhy PM8OIC3WmVEfSdzKenMYMZyKNhjUTeM= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1739204006; 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; bh=MEQtKpqipC+PTN4Th/631XgtJVl5K1IqFh4MSRtsc+U=; b=KNhtOAIqdlWV6qOYrTXWeP+++iuBfbBKZ9WMWfhTnqgZ1/HihNqS9js7JLLhjaaIiIwQCd 4Py43Ics5OgoIU84V1fOpwQTZChdp2qGdQs+LLzp3sZBPv/9ZRTZvqCtXicDVpUpxLgcS7 dr7hVz33oO84gpC/YkinN1RWPGSksc0= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-205-mchbdBHwPjau7YzRQtGOoQ-1; Mon, 10 Feb 2025 11:13:25 -0500 X-MC-Unique: mchbdBHwPjau7YzRQtGOoQ-1 X-Mimecast-MFC-AGG-ID: mchbdBHwPjau7YzRQtGOoQ Received: by mail-wr1-f70.google.com with SMTP id ffacd0b85a97d-38dcc9653a7so1258393f8f.0 for ; Mon, 10 Feb 2025 08:13:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739204004; x=1739808804; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=MEQtKpqipC+PTN4Th/631XgtJVl5K1IqFh4MSRtsc+U=; b=Sws6rJhX+i4EYKxDL8g9wlfHeIKLrM4dzM+P4t1XaM6+O5J0xzvxDbllNtntdMyeJe OgG0QA/bDF2T/kJtGWYg87PZwUuZM/yAA4tE26EP+xMFVXrDZUbhNMlqDrkqadFC9yot /rQP7L19MKyOq2NvPIRLYy21FaoE13aRsV0OczXDnbDrFRmWd/FNEa+VWa94CcIt4eRj U+6IcQZE8KpBLLR6uNfecGdLAUzPw6egkXIlJi88ZMjuI+pT5t7dPrvYvYSgF8ITbGCl xF9Qa+nP43WqAQV0i1yhhVzWB7tEl1o9wqo3v2HQl1vNw84O1nH3gt2GVapnzHmDY1TA 4vdQ== X-Gm-Message-State: AOJu0Yxrgo90QMPHyGosIwm2UfzSt2lV8nbPIib8PwhxiOmy6rIW7KqC 1gw6nLSzI+M7M8/RMy6xq71Z23SJgukVVfKHtLHuDnCAuC9A18yBG0fBMV/wOo1b2AhhWnUNn0o Te89TuY7Ps/AdGAMg/hYexvYczrBensxwLIkV6TK9nQTXFJCg X-Gm-Gg: ASbGncusB7OTn2NEzd3igseRG2TFkKQ2UO0hKmcu5qhnm5qzbtPGjY0cIr13qw3sYpI 3ZEDis4CRkSefXfXhaIP4R8TwxhqzpTq5XYTzSzVzPanuSxkCZ7iV77EHG34FwD/WkAJBZEPDLG gWpVAuQNxYts1ncFkb622hJWOIgn6s/yam0fn7t03V5yn5qD/+OFPjSnia76vu/VkPhEguMdi+f INq1j384F0Igf9aAydpRB2Uuz9/xVHneRQuoYARNsiqqeRJaJCJJet/eBR+hXoBLc4l2pxFJr5m ClrGjyX83eJTnc1NEhxMhzXDOCdFVpmgoQJjmrV3YWqKkIXv++nQTj5LRmtELIZBvQ== X-Received: by 2002:a5d:5f89:0:b0:38d:d932:d9a0 with SMTP id ffacd0b85a97d-38dd932da55mr5624900f8f.50.1739204004106; Mon, 10 Feb 2025 08:13:24 -0800 (PST) X-Google-Smtp-Source: AGHT+IEWPX+Zln5vMuClmopd37CoGtJOZXD7uNSKmeC96slnofVRiwq1aRSVWuCax10ArUWCk6GWqA== X-Received: by 2002:a5d:5f89:0:b0:38d:d932:d9a0 with SMTP id ffacd0b85a97d-38dd932da55mr5624672f8f.50.1739204000328; Mon, 10 Feb 2025 08:13:20 -0800 (PST) Received: from localhost (p200300cbc734b80012c465cd348aaee6.dip0.t-ipconnect.de. [2003:cb:c734:b800:12c4:65cd:348a:aee6]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-4390d93369fsm186995865e9.3.2025.02.10.08.13.17 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 10 Feb 2025 08:13:19 -0800 (PST) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, David Hildenbrand , Andrew Morton , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , John Hubbard , Alistair Popple Subject: [PATCH v1] mm/migrate_device: don't add folio to be freed to LRU in migrate_device_finalize() Date: Mon, 10 Feb 2025 17:13:17 +0100 Message-ID: <20250210161317.717936-1-david@redhat.com> X-Mailer: git-send-email 2.48.1 MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: Jp7Mihf6QcUiBfB7aTos-7MVKZ5v_cc24vewZTCYbN0_1739204004 X-Mimecast-Originator: redhat.com X-Rspam-User: X-Rspamd-Queue-Id: 35A79140011 X-Rspamd-Server: rspam12 X-Stat-Signature: 51iactu9rg9ithnokxrersk3g16n86w5 X-HE-Tag: 1739204007-140512 X-HE-Meta: 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 hQMCe4/T 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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: If migration succeeded, we called folio_migrate_flags()->mem_cgroup_migrate() to migrate the memcg from the old to the new folio. This will set memcg_data of the old folio to 0. Similarly, if migration failed, memcg_data of the dst folio is left unset. If we call folio_putback_lru() on such folios (memcg_data == 0), we will add the folio to be freed to the LRU, making memcg code unhappy. Running the hmm selftests: # ./hmm-tests ... # RUN hmm.hmm_device_private.migrate ... [ 102.078007][T14893] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x7ff27d200 pfn:0x13cc00 [ 102.079974][T14893] anon flags: 0x17ff00000020018(uptodate|dirty|swapbacked|node=0|zone=2|lastcpupid=0x7ff) [ 102.082037][T14893] raw: 017ff00000020018 dead000000000100 dead000000000122 ffff8881353896c9 [ 102.083687][T14893] raw: 00000007ff27d200 0000000000000000 00000001ffffffff 0000000000000000 [ 102.085331][T14893] page dumped because: VM_WARN_ON_ONCE_FOLIO(!memcg && !mem_cgroup_disabled()) [ 102.087230][T14893] ------------[ cut here ]------------ [ 102.088279][T14893] WARNING: CPU: 0 PID: 14893 at ./include/linux/memcontrol.h:726 folio_lruvec_lock_irqsave+0x10e/0x170 [ 102.090478][T14893] Modules linked in: [ 102.091244][T14893] CPU: 0 UID: 0 PID: 14893 Comm: hmm-tests Not tainted 6.13.0-09623-g6c216bc522fd #151 [ 102.093089][T14893] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014 [ 102.094848][T14893] RIP: 0010:folio_lruvec_lock_irqsave+0x10e/0x170 [ 102.096104][T14893] Code: ... [ 102.099908][T14893] RSP: 0018:ffffc900236c37b0 EFLAGS: 00010293 [ 102.101152][T14893] RAX: 0000000000000000 RBX: ffffea0004f30000 RCX: ffffffff8183f426 [ 102.102684][T14893] RDX: ffff8881063cb880 RSI: ffffffff81b8117f RDI: ffff8881063cb880 [ 102.104227][T14893] RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 [ 102.105757][T14893] R10: 0000000000000001 R11: 0000000000000002 R12: ffffc900236c37d8 [ 102.107296][T14893] R13: ffff888277a2bcb0 R14: 000000000000001f R15: 0000000000000000 [ 102.108830][T14893] FS: 00007ff27dbdd740(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000 [ 102.110643][T14893] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 102.111924][T14893] CR2: 00007ff27d400000 CR3: 000000010866e000 CR4: 0000000000750ef0 [ 102.113478][T14893] PKRU: 55555554 [ 102.114172][T14893] Call Trace: [ 102.114805][T14893] [ 102.115397][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170 [ 102.116547][T14893] ? __warn.cold+0x110/0x210 [ 102.117461][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170 [ 102.118667][T14893] ? report_bug+0x1b9/0x320 [ 102.119571][T14893] ? handle_bug+0x54/0x90 [ 102.120494][T14893] ? exc_invalid_op+0x17/0x50 [ 102.121433][T14893] ? asm_exc_invalid_op+0x1a/0x20 [ 102.122435][T14893] ? __wake_up_klogd.part.0+0x76/0xd0 [ 102.123506][T14893] ? dump_page+0x4f/0x60 [ 102.124352][T14893] ? folio_lruvec_lock_irqsave+0x10e/0x170 [ 102.125500][T14893] folio_batch_move_lru+0xd4/0x200 [ 102.126577][T14893] ? __pfx_lru_add+0x10/0x10 [ 102.127505][T14893] __folio_batch_add_and_move+0x391/0x720 [ 102.128633][T14893] ? __pfx_lru_add+0x10/0x10 [ 102.129550][T14893] folio_putback_lru+0x16/0x80 [ 102.130564][T14893] migrate_device_finalize+0x9b/0x530 [ 102.131640][T14893] dmirror_migrate_to_device.constprop.0+0x7c5/0xad0 [ 102.133047][T14893] dmirror_fops_unlocked_ioctl+0x89b/0xc80 Likely, nothing else goes wrong: putting the last folio reference will remove the folio from the LRU again. So besides memcg complaining, adding the folio to be freed to the LRU is just an unnecessary step. The new flow resembles what we have in migrate_folio_move(): add the dst to the lru, remove migration ptes, unlock and unref dst. Fixes: 8763cb45ab96 ("mm/migrate: new memory migration helper for use with device memory") Cc: Andrew Morton Cc: Jérôme Glisse Cc: John Hubbard Cc: Alistair Popple Signed-off-by: David Hildenbrand Reviewed-by: Alistair Popple Tested-by: Alistair Popple --- mm/migrate_device.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) base-commit: e5b2a356dc8a88708d97bd47cca3b8f7ed7af6cb diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 9cf26592ac934..5bd888223cc8b 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -840,20 +840,15 @@ void migrate_device_finalize(unsigned long *src_pfns, dst = src; } + if (!folio_is_zone_device(dst)) + folio_add_lru(dst); remove_migration_ptes(src, dst, 0); folio_unlock(src); - - if (folio_is_zone_device(src)) - folio_put(src); - else - folio_putback_lru(src); + folio_put(src); if (dst != src) { folio_unlock(dst); - if (folio_is_zone_device(dst)) - folio_put(dst); - else - folio_putback_lru(dst); + folio_put(dst); } } }