From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:37291 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750975AbcDRIsN (ORCPT ); Mon, 18 Apr 2016 04:48:13 -0400 From: Anand Jain To: quwenruo@cn.fujitsu.com Cc: linux-btrfs@vger.kernel.org Subject: [PATCH] btrfs: fix btrfs_check_degradable() to free extent map Date: Mon, 18 Apr 2016 16:47:51 +0800 Message-Id: <1460969271-7436-1-git-send-email-anand.jain@oracle.com> In-Reply-To: <1442801443-5132-2-git-send-email-quwenruo@cn.fujitsu.com> References: <1442801443-5132-2-git-send-email-quwenruo@cn.fujitsu.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: I am making the following changes... --------------- 8< ---------------------- Free the extent map and realign the map_tree read_lock to fix the following.. kernel: BUG btrfs_extent_map (Tainted: G B ): Objects remaining in btrfs_extent_map on __kmem_cache_shutdown() kernel: ----------------------------------------------------------------------------- kernel: INFO: Slab 0xffffea0001e4ef80 objects=28 used=9 fp=0xffff8800793be1b0 flags=0x1fffe0000000080 kernel: CPU: 0 PID: 5397 Comm: modprobe Tainted: G B 4.6.0-rc2asj+ #5 kernel: Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 kernel: 0000000000000086 00000000c6b0aa23 ffff880035f3bcf8 ffffffff8141b7e3 kernel: ffffea0001e4ef80 ffff880036994a00 ffff880035f3bdd0 ffffffff81217310 kernel: 0000000000000020 ffff880035f3bde0 ffff880035f3bd90 656a624f00000000 kernel: Call Trace: kernel: [] dump_stack+0x85/0xc2 kernel: [] slab_err+0xb0/0xe0 kernel: [] ? __kmalloc+0x259/0x3a0 kernel: [] ? __kmem_cache_shutdown+0x14c/0x380 kernel: [] __kmem_cache_shutdown+0x16b/0x380 kernel: [] kmem_cache_destroy+0x1fb/0x2b0 kernel: [] extent_map_exit+0x15/0x20 [btrfs] kernel: [] exit_btrfs_fs+0x27/0x1015 [btrfs] kernel: [] SyS_delete_module+0x1b3/0x260 kernel: [] ? exit_to_usermode_loop+0x6a/0xc0 kernel: [] ? trace_hardirqs_on_thunk+0x1b/0x1d kernel: [] entry_SYSCALL_64_fastpath+0x1f/0xbd kernel: INFO: Object 0xffff8800793be240 @offset=576 kernel: INFO: Object 0xffff8800793be2d0 @offset=720 kernel: INFO: Object 0xffff8800793be3f0 @offset=1008 kernel: INFO: Object 0xffff8800793be480 @offset=1152 kernel: INFO: Object 0xffff8800793be7e0 @offset=2016 kernel: INFO: Object 0xffff8800793be870 @offset=2160 kernel: INFO: Object 0xffff8800793be900 @offset=2304 kernel: INFO: Object 0xffff8800793beab0 @offset=2736 kernel: INFO: Object 0xffff8800793bebd0 @offset=3024 Signed-off-by: Anand Jain --- fs/btrfs/volumes.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 91d094ae2a10..36398c9d34eb 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -7105,6 +7105,7 @@ int btrfs_check_degradable(struct btrfs_fs_info *fs_info, unsigned flags) read_lock(&map_tree->map_tree.lock); em = lookup_extent_mapping(&map_tree->map_tree, 0, (u64)(-1)); + read_unlock(&map_tree->map_tree.lock); /* No any chunk? Should be a huge bug */ if (!em) { ret = -ENOENT; @@ -7143,11 +7144,14 @@ int btrfs_check_degradable(struct btrfs_fs_info *fs_info, unsigned flags) * Alwasy search range [next_start, (u64)-1) to find the next * chunk map */ + free_extent_map(em); + read_lock(&map_tree->map_tree.lock); em = lookup_extent_mapping(&map_tree->map_tree, next_start, (u64)(-1) - next_start); + read_unlock(&map_tree->map_tree.lock); } out: - read_unlock(&map_tree->map_tree.lock); + free_extent_map(em); return ret; } -- 2.7.0