From: Jan Kara Date: Fri, 11 Jul 2008 23:27:31 +0000 (-0400) Subject: ext4: Fix lock inversion in ext4_ext_truncate() X-Git-Tag: MMI-PSA29.97-13-9~33675^2~18 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9ddfc3dc75b5cc55ff3cfa586e962d252f1db9d3;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git ext4: Fix lock inversion in ext4_ext_truncate() We cannot call ext4_orphan_add() from under i_data_sem because that causes a lock ordering violation between i_data_sem and and the superblock lock. Updated with Aneesh's locking order fix Signed-off-by: Jan Kara Signed-off-by: Mingming Cao Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index b722bce7d662..7844bbb2bac0 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2768,6 +2768,9 @@ void ext4_ext_truncate(struct inode *inode) if (inode->i_size & (sb->s_blocksize - 1)) ext4_block_truncate_page(handle, mapping, inode->i_size); + if (ext4_orphan_add(handle, inode)) + goto out_stop; + down_write(&EXT4_I(inode)->i_data_sem); ext4_ext_invalidate_cache(inode); @@ -2778,8 +2781,6 @@ void ext4_ext_truncate(struct inode *inode) * Probably we need not scan at all, * because page truncation is enough. */ - if (ext4_orphan_add(handle, inode)) - goto out_stop; /* we have to know where to truncate from in crash case */ EXT4_I(inode)->i_disksize = inode->i_size; @@ -2796,6 +2797,7 @@ void ext4_ext_truncate(struct inode *inode) handle->h_sync = 1; out_stop: + up_write(&EXT4_I(inode)->i_data_sem); /* * If this was a simple ftruncate() and the file will remain alive, * then we need to clear up the orphan record which we created above. @@ -2806,7 +2808,6 @@ out_stop: if (inode->i_nlink) ext4_orphan_del(handle, inode); - up_write(&EXT4_I(inode)->i_data_sem); inode->i_mtime = inode->i_ctime = ext4_current_time(inode); ext4_mark_inode_dirty(handle, inode); ext4_journal_stop(handle);