From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout06.his.huawei.com (canpmsgout06.his.huawei.com [113.46.200.221]) (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 73EA218FDBE for ; Tue, 12 May 2026 01:05:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.221 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778547962; cv=none; b=pSEuVzEBHjfTDkMLsoJHLIG+2ohq9K3zO6rpoa6bAD959evxnXmQMP0tciqzbVFSZlMjkHlJsJ1RyffB5/s+1rTKucrElA1P5BvQlwZqRNjxOz5d1pN0wba1xpEGecGAsFFX6xZ4gnLMXxOFzRdv0hxlWS5szfQeX/XG2kBJo8k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778547962; c=relaxed/simple; bh=+DQ4btyS4r5daySErDKgH6eI6NddiL7mJ3EnAaduJAQ=; h=Subject:To:CC:References:From:Message-ID:Date:MIME-Version: In-Reply-To:Content-Type; b=T+H6ww749jd+PWqv2CEHX3G+MJuhzKu05e3Js1JK/ULrty5JMs2Y6eBRrsJr9EtXr74s4FN6iKRtnJMWvlLvg6MYPvJFCXicGPAMdm9X9rExZZpSfZZkDSxYjIzVDkFC+3eDghC5DUvjJGbfM2xU6Qi2EtUymiNiYaSU18ANwA0= 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=gMa+oL6b; arc=none smtp.client-ip=113.46.200.221 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="gMa+oL6b" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=GU7qv2f6w4gsY9razakdKJCnHrZr7ZxMfRszKHD+pqA=; b=gMa+oL6bYuLM9ZLznpmctfu/JvESgss8Fmg/XeayFoUkh1qu4pt9n5+Yn0xcxpJONsxgBIfnZ scWiBzhDxBkDqhK6zf2yA00m4rJxnPB/vqcrqpLaCSxc9eN/wCLc5RDzZYMOZ7YmWoDRQ2L5DDL 6RLnZPbGuomDEk4TyagSYxQ= Received: from mail.maildlp.com (unknown [172.19.162.140]) by canpmsgout06.his.huawei.com (SkyGuard) with ESMTPS id 4gDyrX6y4czRnZx; Tue, 12 May 2026 08:58:20 +0800 (CST) Received: from kwepemk200017.china.huawei.com (unknown [7.202.194.83]) by mail.maildlp.com (Postfix) with ESMTPS id E1FFD201E9; Tue, 12 May 2026 09:05:56 +0800 (CST) Received: from [10.174.178.219] (10.174.178.219) by kwepemk200017.china.huawei.com (7.202.194.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 12 May 2026 09:05:55 +0800 Subject: Re: "alloc_tag was not set" when running mm/ksft_hmm.sh To: "David Hildenbrand (Arm)" CC: Zenghui Yu , , , , , Andrew Morton , , , , , , , Alistair Popple References: <10e4565a-b416-45d9-a8b0-cd32532b2630@kernel.org> <2b46241c-158b-c9dd-9b81-a98366b2c9fb@huawei.com> From: Zenghui Yu Message-ID: <1986f468-f8f4-c33a-9e02-4d5f833e3560@huawei.com> Date: Tue, 12 May 2026 09:05:55 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To kwepemk200017.china.huawei.com (7.202.194.83) On 2026/5/12 0:38, Zenghui Yu wrote: > Hi David, > > On 5/11/26 8:47 PM, David Hildenbrand (Arm) wrote: > > > > We do have a call to pgalloc_tag_split() in __split_unmapped_folio(), invoked in > > __folio_freeze_and_split_unmapped() before calling > > zone_device_private_split_cb() when iterating the folios. > > If I read the code correctly, pgalloc_tag_split() in > __split_unmapped_folio() deals with device private pages' alloc tag. But > what alloc_tag_sub_check() warns on are real system memory pages (device > page's backing page), which are allocated by > dmirror_devmem_alloc_page()/folio_page(). Sorry, I meant dmirror_devmem_alloc_page()/folio_alloc(). Thanks, Zenghui