On Mon, Jul 01, 2013 at 04:12:27PM -0400, Josef Bacik wrote: > There is another bug in the tree mod log stuff in that we're calling > tree_mod_log_free_eb every single time a block is cow'ed. The problem with this > is that if this block is shared by multiple snapshots we will call this multiple > times per block, so if we go to rewind the mod log for this block we'll BUG_ON() > in __tree_mod_log_rewind because we try to rewind a free twice. We only want to > call tree_mod_log_free_eb if we are actually freeing the block. With this patch > I no longer hit the panic in __tree_mod_log_rewind. Thanks, This fixes my reproducer for __tree_mod_log_rewind() BUG_ON in line 1183. Tested-by: Liu Bo <bo.li.liu@xxxxxxxxxx> > > Signed-off-by: Josef Bacik <jbacik@xxxxxxxxxxxx> > --- > fs/btrfs/ctree.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 32e30ad..127e1fd 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -1093,7 +1093,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, > btrfs_set_node_ptr_generation(parent, parent_slot, > trans->transid); > btrfs_mark_buffer_dirty(parent); > - tree_mod_log_free_eb(root->fs_info, buf); > + if (last_ref) > + tree_mod_log_free_eb(root->fs_info, buf); > btrfs_free_tree_block(trans, root, buf, parent_start, > last_ref); > } > -- > 1.7.7.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
