From e8238f9a8339b3578c85e4192a7a23bc2bdc0333 Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Mon, 8 Apr 2013 13:02:25 -0400 Subject: [PATCH] ext4: fix incorrect lock ordering for ext4_ind_migrate existing locking ordering: journal-> i_data_sem, but ext4_ind_migrate() grab locks in opposite order which may result in deadlock. Signed-off-by: Dmitry Monakhov Signed-off-by: "Theodore Ts'o" --- fs/ext4/extents.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 6c5a70a7b573..ea607f907232 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4735,6 +4735,10 @@ int ext4_ind_migrate(struct inode *inode) (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) return -EINVAL; + handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1); + if (IS_ERR(handle)) + return PTR_ERR(handle); + down_write(&EXT4_I(inode)->i_data_sem); ret = ext4_ext_check_inode(inode); if (ret) @@ -4758,19 +4762,13 @@ int ext4_ind_migrate(struct inode *inode) } } - handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto errout; - } - ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); memset(ei->i_data, 0, sizeof(ei->i_data)); for (i=0; i < len; i++) ei->i_data[i] = cpu_to_le32(blk++); ext4_mark_inode_dirty(handle, inode); - ext4_journal_stop(handle); errout: + ext4_journal_stop(handle); up_write(&EXT4_I(inode)->i_data_sem); return ret; }