From patchwork Tue Feb 11 01:17:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shijie Luo X-Patchwork-Id: 1236118 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-ext4-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=huawei.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48GlKV55qfz9s3x for ; Tue, 11 Feb 2020 12:18:54 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727523AbgBKBSx (ORCPT ); Mon, 10 Feb 2020 20:18:53 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:46568 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727120AbgBKBSx (ORCPT ); Mon, 10 Feb 2020 20:18:53 -0500 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 78672B48A5661A8F30E4; Tue, 11 Feb 2020 09:18:50 +0800 (CST) Received: from huawei.com (10.175.104.225) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.439.0; Tue, 11 Feb 2020 09:18:40 +0800 From: Shijie Luo To: CC: , , , , Subject: [PATCH v2] ext4: add cond_resched() to ext4_protect_reserved_inode Date: Mon, 10 Feb 2020 20:17:52 -0500 Message-ID: <20200211011752.29242-1-luoshijie1@huawei.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-Originating-IP: [10.175.104.225] X-CFilter-Loop: Reflected Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org When journal size is set too big by "mkfs.ext4 -J size=", or when we mount a crafted image to make journal inode->i_size too big, the loop, "while (i < num)", holds cpu too long. This could cause soft lockup. [ 529.357541] Call trace: [ 529.357551] dump_backtrace+0x0/0x198 [ 529.357555] show_stack+0x24/0x30 [ 529.357562] dump_stack+0xa4/0xcc [ 529.357568] watchdog_timer_fn+0x300/0x3e8 [ 529.357574] __hrtimer_run_queues+0x114/0x358 [ 529.357576] hrtimer_interrupt+0x104/0x2d8 [ 529.357580] arch_timer_handler_virt+0x38/0x58 [ 529.357584] handle_percpu_devid_irq+0x90/0x248 [ 529.357588] generic_handle_irq+0x34/0x50 [ 529.357590] __handle_domain_irq+0x68/0xc0 [ 529.357593] gic_handle_irq+0x6c/0x150 [ 529.357595] el1_irq+0xb8/0x140 [ 529.357599] __ll_sc_atomic_add_return_acquire+0x14/0x20 [ 529.357668] ext4_map_blocks+0x64/0x5c0 [ext4] [ 529.357693] ext4_setup_system_zone+0x330/0x458 [ext4] [ 529.357717] ext4_fill_super+0x2170/0x2ba8 [ext4] [ 529.357722] mount_bdev+0x1a8/0x1e8 [ 529.357746] ext4_mount+0x44/0x58 [ext4] [ 529.357748] mount_fs+0x50/0x170 [ 529.357752] vfs_kern_mount.part.9+0x54/0x188 [ 529.357755] do_mount+0x5ac/0xd78 [ 529.357758] ksys_mount+0x9c/0x118 [ 529.357760] __arm64_sys_mount+0x28/0x38 [ 529.357764] el0_svc_common+0x78/0x130 [ 529.357766] el0_svc_handler+0x38/0x78 [ 529.357769] el0_svc+0x8/0xc [ 541.356516] watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [mount:18674] Signed-off-by: Shijie Luo Reviewed-by: Jan Kara --- fs/ext4/block_validity.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c index 1ee04e76bbe0..0a734ffb4310 100644 --- a/fs/ext4/block_validity.c +++ b/fs/ext4/block_validity.c @@ -207,6 +207,7 @@ static int ext4_protect_reserved_inode(struct super_block *sb, return PTR_ERR(inode); num = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits; while (i < num) { + cond_resched(); map.m_lblk = i; map.m_len = num - i; n = ext4_map_blocks(NULL, inode, &map, 0);