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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 04A51CCD1BF for ; Wed, 22 Oct 2025 07:02:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5BE8C8E0017; Wed, 22 Oct 2025 03:02:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5963E8E0002; Wed, 22 Oct 2025 03:02:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4D2BB8E0017; Wed, 22 Oct 2025 03:02:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 3959A8E0002 for ; Wed, 22 Oct 2025 03:02:06 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id D477C1407C9 for ; Wed, 22 Oct 2025 07:02:05 +0000 (UTC) X-FDA: 84024855810.19.3E696D1 Received: from canpmsgout08.his.huawei.com (canpmsgout08.his.huawei.com [113.46.200.223]) by imf13.hostedemail.com (Postfix) with ESMTP id E49C52000D for ; Wed, 22 Oct 2025 07:02:02 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=huawei.com header.s=dkim header.b=hLYeRF9L; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf13.hostedemail.com: domain of linmiaohe@huawei.com designates 113.46.200.223 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1761116524; a=rsa-sha256; cv=none; b=4tiRVw/vemU0Qvm9kOxj77voi+0pEcySpZbM8OErpxEjVrcIvIw4L+DLcNzKFX6rM4r4By vAHB1m1JpliiY8ZWV/eF6+VyvHWGy/IrWECljjXiEv5LofY3/6lHTiaO8RJeeq2YQOhXtc gx8EHttlEF1oMMzyjstUH2WxKaXc2qs= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=huawei.com header.s=dkim header.b=hLYeRF9L; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf13.hostedemail.com: domain of linmiaohe@huawei.com designates 113.46.200.223 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761116524; 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=EHRP3uMAXDZCSqG6N+1vlxdAszjhwtbW5deaNWABMWQ=; b=s33JtNU7yhXIMBO0mn8UEpl9d81R3HpJJMJaF9IlrYrzaduZGlh0kR7qrzIddJxkTBk9Fn RdFnSNa2giUmXIWQ8//XBe5aFUgIHJHlQ+0KMdJcx9fbVBD3Mps50Eh1HEEvsiYgalkwRA z81tjmgcgfTFpMi60yjtn/pNCeEbqT4= dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=EHRP3uMAXDZCSqG6N+1vlxdAszjhwtbW5deaNWABMWQ=; b=hLYeRF9L/tbm9BwldRUCM0HeZZginJ4h9+WkMWqRPxsH4LOMDzdz4E90zWmQoRNClMEbzpw6P HhjKSYDkRwZ2uCj7ymzFT6szIKGDFnNRZM+ap2hGY40M4HwKRxDqZ/Ya2/Isgg0s0kqfxqwWzTv pfyvUnykgL7dyh/ykueDH9I= Received: from mail.maildlp.com (unknown [172.19.88.163]) by canpmsgout08.his.huawei.com (SkyGuard) with ESMTPS id 4cs0Ss0Xn4zmV66; Wed, 22 Oct 2025 15:01:33 +0800 (CST) Received: from dggemv712-chm.china.huawei.com (unknown [10.1.198.32]) by mail.maildlp.com (Postfix) with ESMTPS id 8B80A18001B; Wed, 22 Oct 2025 15:01:57 +0800 (CST) Received: from kwepemq500010.china.huawei.com (7.202.194.235) by dggemv712-chm.china.huawei.com (10.1.198.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 22 Oct 2025 15:01:57 +0800 Received: from [10.173.125.37] (10.173.125.37) by kwepemq500010.china.huawei.com (7.202.194.235) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 22 Oct 2025 15:01:49 +0800 Subject: Re: [PATCH v3] mm/huge_memory: do not change split_huge_page*() target order silently. To: Zi Yan CC: , , , Lorenzo Stoakes , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , "Matthew Wilcox (Oracle)" , Wei Yang , , , , , Pankaj Raghav , , , , , References: <20251017013630.139907-1-ziy@nvidia.com> From: Miaohe Lin Message-ID: <73c5557a-bc84-e1aa-d5d0-ad0ae57b55bb@huawei.com> Date: Wed, 22 Oct 2025 15:01:48 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20251017013630.139907-1-ziy@nvidia.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.125.37] X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemq500010.china.huawei.com (7.202.194.235) X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: E49C52000D X-Stat-Signature: yeewe8656juj1byrh7bx7hgw1awhqqf1 X-HE-Tag: 1761116522-402666 X-HE-Meta: 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 bjN8IDWn 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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 2025/10/17 9:36, Zi Yan wrote: > Page cache folios from a file system that support large block size (LBS) > can have minimal folio order greater than 0, thus a high order folio might > not be able to be split down to order-0. Commit e220917fa507 ("mm: split a > folio in minimum folio order chunks") bumps the target order of > split_huge_page*() to the minimum allowed order when splitting a LBS folio. > This causes confusion for some split_huge_page*() callers like memory > failure handling code, since they expect after-split folios all have > order-0 when split succeeds but in reality get min_order_for_split() order > folios and give warnings. > > Fix it by failing a split if the folio cannot be split to the target order. > Rename try_folio_split() to try_folio_split_to_order() to reflect the added > new_order parameter. Remove its unused list parameter. > > Fixes: e220917fa507 ("mm: split a folio in minimum folio order chunks") > [The test poisons LBS folios, which cannot be split to order-0 folios, and > also tries to poison all memory. The non split LBS folios take more memory > than the test anticipated, leading to OOM. The patch fixed the kernel > warning and the test needs some change to avoid OOM.] > Reported-by: syzbot+e6367ea2fdab6ed46056@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/all/68d2c943.a70a0220.1b52b.02b3.GAE@google.com/ > Cc: stable@vger.kernel.org > Signed-off-by: Zi Yan > Reviewed-by: Luis Chamberlain > Reviewed-by: Pankaj Raghav > Reviewed-by: Wei Yang Thanks for your patch. LGTM. Reviewed-by: Miaohe Lin Thanks. .