From nobody Tue Dec 23 16:22:44 2025 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (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 4F1AF231A50 for ; Mon, 13 Jan 2025 08:34:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.187 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736757281; cv=none; b=KcgPc0AxWE3LMaPc4PSK0JWozL4Fdq4n+k5nKsvh32gXMvJHgSIf/mMkQrfl/l4t/xXUFefj8fsujsV2VqnU8DUIfbAfbKntWf/sjghO6L4+4v4E/DnggcZcnf4UxkzZzSeMvOAKu/iR74Ca4OslnLpAKNEfaCDHSXoR21uiSz0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736757281; c=relaxed/simple; bh=nOFI/X7mQDNuyZxJbFCr9EIxMrBCya1Zieufc6IZnrM=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=rYfPS8pQYf5szGSZaShUsLEeOXSHEIWN/5sFdH/m8JnZK/5PjGhu0i0BMC9QOLc3dRruhF40Zn46SqdQndb941LtkgaymcN3kWrc0CL/KO4QXSxDO31bkehM/aLJZ0eUSRaSahfwOjHLSPPdKnrJcBCxN3aaojay+hfN8PTj0aE= 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; arc=none smtp.client-ip=45.249.212.187 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 Received: from mail.maildlp.com (unknown [172.19.88.105]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4YWlpw1Kcnz11SR8; Mon, 13 Jan 2025 16:31:36 +0800 (CST) Received: from kwepemg100017.china.huawei.com (unknown [7.202.181.58]) by mail.maildlp.com (Postfix) with ESMTPS id 4A6FE1401E9; Mon, 13 Jan 2025 16:34:36 +0800 (CST) Received: from huawei.com (10.175.124.71) by kwepemg100017.china.huawei.com (7.202.181.58) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 13 Jan 2025 16:34:35 +0800 From: Wupeng Ma To: , , , , , CC: , , Subject: [PATCH 2/2] hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio Date: Mon, 13 Jan 2025 16:27:17 +0800 Message-ID: <20250113082718.1872494-3-mawupeng1@huawei.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250113082718.1872494-1-mawupeng1@huawei.com> References: <20250113082718.1872494-1-mawupeng1@huawei.com> 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: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemg100017.china.huawei.com (7.202.181.58) Content-Type: text/plain; charset="utf-8" From: Ma Wupeng Commit b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined) add page poison checks in do_migrate_range in order to make offline hwpoisoned page possible by introducing isolate_lru_page and try_to_unmap for hwpoisoned page. However folio lock must be held before calling try_to_unmap. Add it to fix this problem. Waring will be produced if filio is not locked during unmap: ------------[ cut here ]------------ kernel BUG at ./include/linux/swapops.h:400! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G W 6.13.0-rc1= -00016-g3c434c7ee82a-dirty #41 Tainted: [W]=3DWARN Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=3D--) pc : try_to_unmap_one+0xb08/0xd3c lr : try_to_unmap_one+0x3dc/0xd3c Call trace: try_to_unmap_one+0xb08/0xd3c (P) try_to_unmap_one+0x3dc/0xd3c (L) rmap_walk_anon+0xdc/0x1f8 rmap_walk+0x3c/0x58 try_to_unmap+0x88/0x90 unmap_poisoned_folio+0x30/0xa8 do_migrate_range+0x4a0/0x568 offline_pages+0x5a4/0x670 memory_block_action+0x17c/0x374 memory_subsys_offline+0x3c/0x78 device_offline+0xa4/0xd0 state_store+0x8c/0xf0 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x118/0x1a8 vfs_write+0x3a8/0x4bc ksys_write+0x6c/0xf8 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x100 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x30/0xd0 el0t_64_sync_handler+0xc8/0xcc el0t_64_sync+0x198/0x19c Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000) ---[ end trace 0000000000000000 ]--- Fixes: b15c87263a69 ("hwpoison, memory_hotplug: allow hwpoisoned pages to b= e offlined") Signed-off-by: Ma Wupeng --- mm/memory_hotplug.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 330668d37e44..9bedecfc3577 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1805,8 +1805,12 @@ static void do_migrate_range(unsigned long start_pfn= , unsigned long end_pfn) (folio_test_large(folio) && folio_test_has_hwpoisoned(folio))) { if (WARN_ON(folio_test_lru(folio))) folio_isolate_lru(folio); - if (folio_mapped(folio)) + if (folio_mapped(folio)) { + folio_lock(folio); unmap_poisoned_folio(folio, TTU_IGNORE_MLOCK | TTU_HWPOISON); + folio_unlock(folio); + } + continue; } =20 --=20 2.25.1