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 X-Spam-Level: X-Spam-Status: No, score=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E036C43387 for ; Mon, 7 Jan 2019 12:44:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC8D82177B for ; Mon, 7 Jan 2019 12:44:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546865064; bh=7FM8rQlGaF3UaAGH7esqC51CMM4smE5DF4gHHPFah/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=t+xMf9W+RxRKLlbEVv7tGii3Zm51lA9F6Lw/4VRo3Z/rQcVziun3rV7JkrDc7ZvcV Dk0cdCbvdzRemqC1lrgyefoaEXFDnxjQ4C91S6iVeKYXTcSlGpYC2Yxze3QxqVrbGO XsTlqnHNtGWvjCJxvgFUB1XABPLcPlMAP6BDSc14= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728740AbfAGMoX (ORCPT ); Mon, 7 Jan 2019 07:44:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:60970 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727324AbfAGMoS (ORCPT ); Mon, 7 Jan 2019 07:44:18 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 46FE220449; Mon, 7 Jan 2019 12:44:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546865056; bh=7FM8rQlGaF3UaAGH7esqC51CMM4smE5DF4gHHPFah/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pCAnon3pPVPBlg6mD7dE89lyq0Ckh89O6BmfI9bqplPOArY+YbL/ocsYMrPDP+/rY rZG0CpmGhQUelc8cv8NdewS6vPjeP9beL0Jo/o33ayu8SMYETkq34gCgg3IY97LSkz GmGNQp6riwghJDNsH3Lst2b5DPBSpmIo4odCFkWU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Filipe Manana , Lu Fengqi , David Sterba Subject: [PATCH 4.20 095/145] btrfs: skip file_extent generation check for free_space_inode in run_delalloc_nocow Date: Mon, 7 Jan 2019 13:32:12 +0100 Message-Id: <20190107104449.647750834@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190107104437.308206189@linuxfoundation.org> References: <20190107104437.308206189@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lu Fengqi commit 27a7ff554e8d349627a90bda275c527b7348adae upstream. The test case btrfs/001 with inode_cache mount option will encounter the following warning: WARNING: CPU: 1 PID: 23700 at fs/btrfs/inode.c:956 cow_file_range.isra.19+0x32b/0x430 [btrfs] CPU: 1 PID: 23700 Comm: btrfs Kdump: loaded Tainted: G W O 4.20.0-rc4-custom+ #30 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:cow_file_range.isra.19+0x32b/0x430 [btrfs] Call Trace: ? free_extent_buffer+0x46/0x90 [btrfs] run_delalloc_nocow+0x455/0x900 [btrfs] btrfs_run_delalloc_range+0x1a7/0x360 [btrfs] writepage_delalloc+0xf9/0x150 [btrfs] __extent_writepage+0x125/0x3e0 [btrfs] extent_write_cache_pages+0x1b6/0x3e0 [btrfs] ? __wake_up_common_lock+0x63/0xc0 extent_writepages+0x50/0x80 [btrfs] do_writepages+0x41/0xd0 ? __filemap_fdatawrite_range+0x9e/0xf0 __filemap_fdatawrite_range+0xbe/0xf0 btrfs_fdatawrite_range+0x1b/0x50 [btrfs] __btrfs_write_out_cache+0x42c/0x480 [btrfs] btrfs_write_out_ino_cache+0x84/0xd0 [btrfs] btrfs_save_ino_cache+0x551/0x660 [btrfs] commit_fs_roots+0xc5/0x190 [btrfs] btrfs_commit_transaction+0x2bf/0x8d0 [btrfs] btrfs_mksubvol+0x48d/0x4d0 [btrfs] btrfs_ioctl_snap_create_transid+0x170/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x124/0x180 [btrfs] btrfs_ioctl+0x123f/0x3030 [btrfs] The file extent generation of the free space inode is equal to the last snapshot of the file root, so the inode will be passed to cow_file_rage. But the inode was created and its extents were preallocated in btrfs_save_ino_cache, there are no cow copies on disk. The preallocated extent is not yet in the extent tree, and btrfs_cross_ref_exist will ignore the -ENOENT returned by check_committed_ref, so we can directly write the inode to the disk. Fixes: 78d4295b1eee ("btrfs: lift some btrfs_cross_ref_exist checks in nocow path") CC: stable@vger.kernel.org # 4.18+ Reviewed-by: Filipe Manana Signed-off-by: Lu Fengqi Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1372,7 +1372,8 @@ next_slot: * Do the same check as in btrfs_cross_ref_exist but * without the unnecessary search. */ - if (btrfs_file_extent_generation(leaf, fi) <= + if (!nolock && + btrfs_file_extent_generation(leaf, fi) <= btrfs_root_last_snapshot(&root->root_item)) goto out_check; if (extent_type == BTRFS_FILE_EXTENT_REG && !force)