Looback bugfix

[Jan Kara]

  Hello,

  I'm sending you a patch which should fix bug in loopback device - it
allows you to setup loopback /dev/loop0 -> /dev/loop0 with very unpleasant
(hard deadlock) results. The patch is against 2.4.16 but should apply well
against 2.5.0 too. Could oth of you apply the patch please?

							Bye

								Honza

--
Jan Kara <[e-mail]>
SuSE CR Labs

------- <cut> ---------

diff -ruX /home/jack/.kerndiffexclude linux-2.4.16/drivers/block/loop.c linux-2.4.16-loopfix/drivers/block/loop.c
--- linux-2.4.16/drivers/block/loop.c	Mon Nov 19 23:48:02 2001
+++ linux-2.4.16-loopfix/drivers/block/loop.c	Sat Dec  1 00:07:39 2001
@@ -640,6 +640,10 @@
 
 	if (S_ISBLK(inode->i_mode)) {
 		lo_device = inode->i_rdev;
+		if (lo_device == dev) {
+			error = -EBUSY;
+			goto out;
+		}
 	} else if (S_ISREG(inode->i_mode)) {
 		struct address_space_operations *aops = inode->i_mapping->a_ops;
 		/*