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 98B55FA3742 for ; Thu, 27 Oct 2022 11:37:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C252B8E0002; Thu, 27 Oct 2022 07:37:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BADAF8E0001; Thu, 27 Oct 2022 07:37:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A4DFB8E0002; Thu, 27 Oct 2022 07:37:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 8E6C88E0001 for ; Thu, 27 Oct 2022 07:37:39 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 47B671A0961 for ; Thu, 27 Oct 2022 11:37:39 +0000 (UTC) X-FDA: 80066529438.22.E8ADC7A Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf18.hostedemail.com (Postfix) with ESMTP id D83671C0011 for ; Thu, 27 Oct 2022 11:37:35 +0000 (UTC) Received: from dggpeml500026.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Myk7903wHz15Lwm; Thu, 27 Oct 2022 19:32:37 +0800 (CST) Received: from [10.174.179.110] (10.174.179.110) by dggpeml500026.china.huawei.com (7.185.36.106) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 27 Oct 2022 19:37:30 +0800 Message-ID: <6e9d8e46-708a-a431-b673-a5cb5b46ad86@huawei.com> Date: Thu, 27 Oct 2022 19:37:30 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.1 Subject: Re: [PATCH STABLE 5.10] mm/memory: add non-anonymous page check in the copy_present_page() Content-Language: en-US To: Greg KH CC: , , , , References: <20221024094911.3054769-1-songyuanzheng@huawei.com> From: songyuanzheng In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.110] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpeml500026.china.huawei.com (7.185.36.106) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666870657; a=rsa-sha256; cv=none; b=M3M3S0jmnLxS+ariP884183EuljfymNQItm/DC7t5kHUGIxX3c+Ioa9ui+Tp90hRmopBsL MC/afdwcVKA1vkC5PBdaTomxoCl+XjyB2Wj/8Zq2hVMao4D0TIs2mJfDKCaQqNsmBqxEik 8aw3MW94dODkwXpDRjjtjaQgdZzJruI= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=none; spf=pass (imf18.hostedemail.com: domain of songyuanzheng@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=songyuanzheng@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666870657; 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; bh=KxeeV1LpmsBVFGx4NbI6llWFwGGso4SOZF7LREsnOv4=; b=TbKmfD2nUboa0kyq0lde6nNOrMQrpXZpclcPP2kNo6mtjgrmGCHsVwu4XaopVBZ/ilAqjM C83EuF/9t1WqLtgKasWrakSsnsiktgKee5m5PiaLOVNcq9363i/toAVPw6Sc4B0qOM9hlR 7O+t6FusWRs5ONIMynuprb196nmmZso= X-Rspamd-Queue-Id: D83671C0011 X-Rspam-User: Authentication-Results: imf18.hostedemail.com; dkim=none; spf=pass (imf18.hostedemail.com: domain of songyuanzheng@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=songyuanzheng@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspamd-Server: rspam04 X-Stat-Signature: sxrfpoppypsh5pk93aiktirkjhb9fe5z X-HE-Tag: 1666870655-654942 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: Hi, Greg KH, Currently, this patch is under review and no correct solution is available to solve this problem. After a perfect patch is available, I will send the corresponding patch to 5.15y. On 2022/10/27 0:52, Greg KH wrote: > On Mon, Oct 24, 2022 at 09:49:11AM +0000, Yuanzheng Song wrote: >> The vma->anon_vma of the child process may be NULL because >> the entire vma does not contain anonymous pages. In this >> case, a BUG will occur when the copy_present_page() passes >> a copy of a non-anonymous page of that vma to the >> page_add_new_anon_rmap() to set up new anonymous rmap. >> >> ------------[ cut here ]------------ >> kernel BUG at mm/rmap.c:1044! >> Internal error: Oops - BUG: 0 [#1] SMP >> Modules linked in: >> CPU: 2 PID: 3617 Comm: test Not tainted 5.10.149 #1 >> Hardware name: linux,dummy-virt (DT) >> pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) >> pc : __page_set_anon_rmap+0xbc/0xf8 >> lr : __page_set_anon_rmap+0xbc/0xf8 >> sp : ffff800014c1b870 >> x29: ffff800014c1b870 x28: 0000000000000001 >> x27: 0000000010100073 x26: ffff1d65c517baa8 >> x25: ffff1d65cab0f000 x24: ffff1d65c416d800 >> x23: ffff1d65cab5f248 x22: 0000000020000000 >> x21: 0000000000000001 x20: 0000000000000000 >> x19: fffffe75970023c0 x18: 0000000000000000 >> x17: 0000000000000000 x16: 0000000000000000 >> x15: 0000000000000000 x14: 0000000000000000 >> x13: 0000000000000000 x12: 0000000000000000 >> x11: 0000000000000000 x10: 0000000000000000 >> x9 : ffffc3096d5fb858 x8 : 0000000000000000 >> x7 : 0000000000000011 x6 : ffff5a5c9089c000 >> x5 : 0000000000020000 x4 : ffff5a5c9089c000 >> x3 : ffffc3096d200000 x2 : ffffc3096e8d0000 >> x1 : ffff1d65ca3da740 x0 : 0000000000000000 >> Call trace: >> __page_set_anon_rmap+0xbc/0xf8 >> page_add_new_anon_rmap+0x1e0/0x390 >> copy_pte_range+0xd00/0x1248 >> copy_page_range+0x39c/0x620 >> dup_mmap+0x2e0/0x5a8 >> dup_mm+0x78/0x140 >> copy_process+0x918/0x1a20 >> kernel_clone+0xac/0x638 >> __do_sys_clone+0x78/0xb0 >> __arm64_sys_clone+0x30/0x40 >> el0_svc_common.constprop.0+0xb0/0x308 >> do_el0_svc+0x48/0xb8 >> el0_svc+0x24/0x38 >> el0_sync_handler+0x160/0x168 >> el0_sync+0x180/0x1c0 >> Code: 97f8ff85 f9400294 17ffffeb 97f8ff82 (d4210000) >> ---[ end trace a972347688dc9bd4 ]--- >> Kernel panic - not syncing: Oops - BUG: Fatal exception >> SMP: stopping secondary CPUs >> Kernel Offset: 0x43095d200000 from 0xffff800010000000 >> PHYS_OFFSET: 0xffffe29a80000000 >> CPU features: 0x08200022,61806082 >> Memory Limit: none >> ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]--- >> >> This problem has been fixed by the fb3d824d1a46 >> ("mm/rmap: split page_dup_rmap() into page_dup_file_rmap() and page_try_dup_anon_rmap()"), >> but still exists in the linux-5.10.y branch. >> >> This patch is not applicable to this version because >> of the large version differences. Therefore, fix it by >> adding non-anonymous page check in the copy_present_page(). >> >> Fixes: 70e806e4e645 ("mm: Do early cow for pinned pages during fork() for ptes") >> Signed-off-by: Yuanzheng Song >> --- >> mm/memory.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) > > We also need this in 5.15.y, right? Can you provide a working version > for there so that no one upgrades from 5.10.y to 5.15.y and has a > regression? > > I'll wait for that before taking this one. > > thanks, > > greg k-h > . > Thanks, Yuanzheng .