It appears that a minor thinko occurred in udf_rmdir and the (already-cleared)
link count on the directory that is being removed was being decremented
instead of the link count on its parent directory. This gives rise to lots of
kernel messages similar to:
UDF-fs warning (device loop1): udf_rmdir: empty directory has nlink != 2 (8)
when removing directory trees. No other ill effects have been observed but I
guess it could theoretically result in the link count overflowing on a very
long-lived, much modified directory.
Signed-off-by: Stephen Mollett <[email protected]>
---
Patch applies cleanly to latest git snapshot and other recent 2.6 kernels.
Please CC: me as I'm not currently subscribed to linux-kernel.
First attempt at formally submitting a kernel patch - apologies if I've cocked
something up - please be nice :-)
--- linux-2.6.21/fs/udf/namei.c.orig 2007-05-01 18:52:02.000000000 +0100
+++ linux-2.6.21/fs/udf/namei.c 2007-05-01 18:53:00.000000000 +0100
@@ -878,7 +878,7 @@ static int udf_rmdir(struct inode * dir,
inode->i_nlink);
clear_nlink(inode);
inode->i_size = 0;
- inode_dec_link_count(inode);
+ inode_dec_link_count(dir);
inode->i_ctime = dir->i_ctime = dir->i_mtime = current_fs_time(dir->i_sb);
mark_inode_dirty(dir);
On Tue, 1 May 2007 19:23:14 +0100
Stephen Mollett <[email protected]> wrote:
> It appears that a minor thinko occurred in udf_rmdir and the (already-cleared)
> link count on the directory that is being removed was being decremented
> instead of the link count on its parent directory. This gives rise to lots of
> kernel messages similar to:
>
> UDF-fs warning (device loop1): udf_rmdir: empty directory has nlink != 2 (8)
>
> when removing directory trees. No other ill effects have been observed but I
> guess it could theoretically result in the link count overflowing on a very
> long-lived, much modified directory.
>
> Signed-off-by: Stephen Mollett <[email protected]>
> ---
>
> Patch applies cleanly to latest git snapshot and other recent 2.6 kernels.
>
> Please CC: me as I'm not currently subscribed to linux-kernel.
>
> First attempt at formally submitting a kernel patch - apologies if I've cocked
> something up - please be nice :-)
>
>
> --- linux-2.6.21/fs/udf/namei.c.orig 2007-05-01 18:52:02.000000000 +0100
> +++ linux-2.6.21/fs/udf/namei.c 2007-05-01 18:53:00.000000000 +0100
> @@ -878,7 +878,7 @@ static int udf_rmdir(struct inode * dir,
> inode->i_nlink);
> clear_nlink(inode);
> inode->i_size = 0;
> - inode_dec_link_count(inode);
> + inode_dec_link_count(dir);
> inode->i_ctime = dir->i_ctime = dir->i_mtime = current_fs_time(dir->i_sb);
> mark_inode_dirty(dir);
>
OK, thanks. git-blame says
9a53c3a7 (Dave Hansen 2006-09-30 23:29:03 -0700 881) inode_dec_link_count(inode);
This bug is also fixed in Jan's UDF fixes for 2.6.22, but it looks like I
should make your fix a separate thing, with a 2.6.21.x backport.